U.S. patent application number 12/268972 was filed with the patent office on 2009-05-28 for imaging device and control method for imaging device.
Invention is credited to Keiji Kunishige, Satoshi Miyazaki, Yoji Watanabe.
Application Number | 20090135295 12/268972 |
Document ID | / |
Family ID | 40669371 |
Filed Date | 2009-05-28 |
United States Patent
Application |
20090135295 |
Kind Code |
A1 |
Kunishige; Keiji ; et
al. |
May 28, 2009 |
IMAGING DEVICE AND CONTROL METHOD FOR IMAGING DEVICE
Abstract
An imaging device of the present invention comprises an imaging
section, including an image sensor for imaging a subject, for
generating image data based on output signals of the image sensor;
a control section for casing repeated operation of the imaging
section in accordance with a single release operation; an adding
processing section for sequentially adding image data repeatedly
output from the imaging section and generating added mage data; an
image display section for displaying the added image data; and a
setting section for setting a repeat period for the imaging section
and instructing to the control section. Also, an imaging device of
the present invention, comprises an imaging section for repeatedly
forming an image of a subject at a set period, while performing a
bulb exposure operation, and outputting image data; an adding
processing section for performing adding processing of the image
data and previously output image data; an added image storage
section for respectively independently storing a plurality of added
images that have been added by the adding processing section, and a
display section for displaying, in a list, the plurality of added
images that have been stored in the added image storage section
after completion of the bulb exposure operation.
Inventors: |
Kunishige; Keiji; (Tokyo,
JP) ; Miyazaki; Satoshi; (Tokyo, JP) ;
Watanabe; Yoji; (Tokyo, JP) |
Correspondence
Address: |
STRAUB & POKOTYLO
788 Shrewsbury Avenue
Tinton Falls
NJ
07724
US
|
Family ID: |
40669371 |
Appl. No.: |
12/268972 |
Filed: |
November 11, 2008 |
Current U.S.
Class: |
348/362 ;
348/E5.034 |
Current CPC
Class: |
H04N 5/23293 20130101;
H04N 5/35572 20130101; H04N 5/232122 20180801; H04N 5/2353
20130101; H04N 5/23232 20130101; H04N 5/357 20130101; H04N 5/232935
20180801; H04N 5/235 20130101; H04N 5/232939 20180801; H04N 5/2355
20130101; H04N 5/232411 20180801 |
Class at
Publication: |
348/362 ;
348/E05.034 |
International
Class: |
H04N 5/235 20060101
H04N005/235 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 20, 2007 |
JP |
2007-301017 |
Nov 20, 2007 |
JP |
2007-301018 |
Nov 28, 2007 |
JP |
2007-306904 |
Nov 28, 2007 |
JP |
2007-306905 |
Dec 5, 2007 |
JP |
2007-314903 |
Claims
1. An imaging device, comprising: an imaging section, including an
image sensor for imaging a subject, for generating image data based
on output signals of the image sensor; a control section for
causing repeated operation of the imaging section in response to a
single release operation; an adding processing section for
sequentially adding image data repeatedly output from the imaging
section and generating added mage data; an image display section
for displaying the added image data; and a setting section for
setting a repeat period for the imaging section and instructing to
the control section.
2. The imaging device of claim 1, wherein: the setting section sets
a repeat period for the imaging section to within a predetermined
range in response to a manual operation.
3. The imaging device of claim 1, wherein: the setting section
changes the repeat period for the imaging section according to a
brightness level of the added image data.
4. The imaging device of claim 1, wherein: the setting section
controls an upper limit value of the repeat period for the imaging
section according to a dark current characteristic of the image
sensor.
5. The imaging device of claim 1, wherein: the setting section
changes the repeat period for the imaging section according to a
set shutter speed.
6. The imaging device of claim 1, wherein: the control section
repeatedly operates the imaging section in response to a first
operation of a release button, and stops an imaging operation of
the imaging section in response to a second operation of the
release button.
7. The imaging device of claim 1, wherein: the image processing
section comprises a temporary storage section for independently
storing image data sequentially output from the imaging section,
and an addition processing section for reading out and adding image
data stored in the temporary storage section.
8. The imaging device of claim 1, wherein: for a specified period
from commencement of a bulb exposure, notification information
indicating that the bulb exposure is being executed is displayed on
the image display section instead of the added image.
9. The imaging device of claim 8, wherein: the specified period is
a period until a brightness level of the added image reaches a
predetermined level.
10. The imaging device of claim 8, wherein: the specified period is
a period until an elapsed time from commencement of the bulb
exposure reaches a predetermined value.
11. The imaging device of claim 8, wherein: after elapse of the
specified period, the added image is displayed, and at the same
time notification information indicating that the bulb exposure is
being executed is displayed superimposed on part of the added
image.
12. The imaging device of claim 8, wherein: the notification
information is further display of elapsed time from commencement of
the bulb exposure.
13. The imaging device of claim 1, further comprising: a display
illumination section for illuminating a display screen of the image
display section, in association with update of image display on the
image display section, for only a predetermined time.
14. The imaging device of claim 13, wherein: the display
illumination section continuously carries out the illumination in
the event that a cycle time for image display on the image display
section is less than a predetermined time.
15. The imaging device of claim 13, wherein: an update operation
member is provided for instructing update of the display section,
and if the update operation member is operated update of the image
display is carried out, and illumination of the image display
section is carried out.
16. The imaging device of claim 13, wherein: a cycle time setting
operation member for setting a cycle time for image display is
provided, and the cycle time is changed if the cycle time setting
operation member is operated during execution of the bulb
exposure.
17. The imaging device of claim 1, further comprising: a sound
generating section for emitting sound for a predetermined time, in
association with update of image display on the image display
section.
18. The imaging device of claim 17, wherein: the sound generating
carries out emission of the sound for the predetermined time in the
event that a cycle time for image display on the image display
section is a predetermined value or greater.
19. An imaging device, comprising: an imaging section for
repeatedly forming a subject image at a set period during a bulb
exposure operation, and outputting image data; an adding processing
section for adding the mage data and image data previously output;
an added image storage section for respectively independently
storing a plurality of added images added by the adding processing
section; and a display section for, after completion of the bulb
exposure, displaying a plurality of added mages stored in the added
image storage section in the form of a list.
20. The imaging device of claim 19, further comprising: a selection
section for selecting any one added image from a plurality of added
images displayed on the display section; and an image storage
section for storing the added image that has been selected by the
selection section.
21. The imaging device of claim 20, wherein: the selection section
includes an operation member capable of being manually operated,
and a display section for displaying, in a list, thumbnail images
corresponding to a plurality of added images data stored in the
added image storage section, and if a single thumbnail image is
selected by operation of the operation member, a corresponding one
of the plurality of added images stored in the added image storage
section is selected.
22. A control method for an imaging device for exposing a subject,
in response to a first release operation, comprising: repeatedly
imaging a subject; generating image data based on the imaged
subject; sequentially adding image data; and repeatedly displaying
added image data.
23. A control method for an imaging device for exposing a subject,
in response to a first release operation, comprising: repeatedly
imaging a subject; generating image data based on the imaged
subject; sequentially adding image data; successively storing added
image data; and after exposure, displaying stored image data in a
list.
24. A computer readable storage medium storing a program for
controlling an imaging device for exposing a subject in response to
a first release operation, comprising: repeatedly imaging a
subject; generating image data based on the imaged subject;
sequentially adding image data; and repeatedly displaying added
image data.
25. A computer readable storage medium storing a program for
controlling an imaging device for exposing a subject in response to
a first release operation, comprising: repeatedly imaging a
subject; generating image data based on the imaged subject;
sequentially adding image data; successively storing added image
data; and after exposure, displaying stored image data in a list.
Description
[0001] Benefit is claimed, under 35 U.S.C. .sctn. 119, to the
filing dates of prior Japanese Patent Applications No. 2007-301017
filed on Nov. 20, 2007, No. 2007-301018 filed on Nov. 20, 2007, No.
2007-306904 filed on Nov. 28, 2007, No. 2007-306905 filed on Nov.
28, 2007, No. 2007-314903 filed on Dec. 5, 2007. These applications
are expressly incorporated herein by reference. The scope of the
present invention is not limited to any requirements of the
specific embodiments described in the applications.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an imaging device and a
control method for an imaging device, and in more detail relates to
an imaging device capable of imaging a subject while carrying out
bulb exposure or long time exposure etc., and to a control method
for an imaging device.
[0004] 2. Description of the Related Art
[0005] Generally, in the case of imaging a subject such as a starry
ski, fireworks or a night scene, the bulb exposure setting is often
used. However, with bulb exposure appropriate exposure time (time
from opening the shutter to closing the shutter) varies depending
on the photographed image and ambient conditions, and it was
necessary for the photographer to determine exposure time on their
own without looking at a completed image. Therefore, if that
determination was wrong, there was a problem of over or under
exposure.
[0006] At the time of bulb exposure therefore, if a photographed
image can be observed according to exposure, it will be possible to
observe exposure levels in real time, and determining exposure time
will be simplified. For example, Unexamined Japanese patent
application No. 2005-117395 (laid-open Apr. 28, 2005) discloses am
imaging device for acquiring image signals from an image sensor at
specified time intervals (for example, 1/10th of a second) during
an exposure operation, and displaying a sequentially summed image
on a liquid crystal monitor.
SUMMARY OF THE INVENTION
[0007] The present invention has as its object to provide an
imaging device with which a photographer can recognize that an
exposure operation is progressing, in a long time exposure such as
bulb exposure, and a control method for an imaging device.
[0008] According to the present invention, there is provided an
imaging device, comprising: an imaging section, including an image
sensor for imaging a subject, for generating image data based on
output signals of the image sensor; a control section for causing
repeated operation of the imaging section in accordance with a
single release operation; an adding processing section for
sequentially adding image data repeatedly output from the imaging
section and generating added mage data; an image display section
for displaying the added image data, and a setting section for
setting a repeat period for the imaging section and instructing to
the control section.
[0009] There is also provided an imaging device of the present
invention, comprising: an imaging section for repeatedly forming an
image of a subject at a set period, while performing a bulb
exposure operation, and outputting image data; an adding processing
section for performing adding processing of the image data and
previously output image data; an added image storage section for
respectively independently storing a plurality of added images that
have been added by the adding processing section; and a display
section for displaying, in a list, the plurality of added images
that have been stored in the added image storage section after
completion of the bulb exposure operation.
[0010] Further, a control method for an imaging device of the
present invention comprises: repeatedly forming an image of a
subject, generating image data based on the formed subject image,
sequentially adding image data, and repeatedly displaying added
image data.
[0011] Further, a control method for an imaging device of the
present invention comprises: repeatedly forming an image of a
subject, generating image data based on the formed subject image,
sequentially adding image data, successively storing added image
data, and performing list display of the stored image data, after
exposure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is an external perspective drawing looking at a
digital single lens reflex camera of a first embodiment of the
present invention from a rear surface.
[0013] FIG. 2 is a block diagram showing the overall structure of
electrical systems of a digital single lens reflex camera relating
to a first embodiment of the present invention.
[0014] FIG. 3 is a block diagram showing in abstract form the
structure relating to image forming and display in bulb mode etc.,
in a digital single lens reflex camera of the first embodiment of
the present invention.
[0015] FIG. 4 is a flowchart showing a power on reset operation of
the first embodiment of the present invention.
[0016] FIG. 5 is a flowchart showing a cycle time input operation
of the first embodiment of the present invention.
[0017] FIG. 6 is a flowchart showing a shooting operation of the
first embodiment of the present invention.
[0018] FIG. 7 is a flowchart showing an exposure operation of the
first embodiment of the present invention.
[0019] FIG. 8 shows respective regions of an image sensor of a
digital single lens reflex camera relating to a first embodiment of
the present invention.
[0020] FIG. 9 is a graph showing a relationship between
temperature, relating to dark current, and integration level in an
image sensor of a digital single lens reflex camera of the first
embodiment of the present invention.
[0021] FIG. 10 shows exposure information display of a digital
single lens reflex camera relating to a first embodiment of the
present invention.
[0022] FIG. 11 shows update display for a digital single lens
reflex camera of the first embodiment of the invention, with FIG.
11(a) to FIG. 11(e) showing display of respectively different cycle
times.
[0023] FIG. 12 shows display of bulb mode exposure time for the
first embodiment of the invention, with FIG. 12(a) to FIG. 12(g)
showing change with lapse of cycle time.
[0024] FIG. 13 is a flowchart showing a power-on reset operation of
a second embodiment of the present invention.
[0025] FIG. 14 is a flowchart showing an exposure operation of the
second embodiment of the present invention.
[0026] FIG. 15 is a flowchart showing resetting of cycle time in a
second embodiment of the present invention.
[0027] FIG. 16 is a block diagram showing the overall structure of
electrical systems of a digital single lens reflex camera relating
to a third embodiment of the present invention.
[0028] FIG. 17 is a block diagram showing in abstract form the
structure relating to image forming and display in bulb mode etc.,
in a digital single lens reflex camera of the third embodiment of
the present invention.
[0029] FIG. 18 is a flowchart showing a cycle time input operation
of the third embodiment of the present invention.
[0030] FIG. 19 is a flowchart showing an exposure operation of the
third embodiment of the present invention.
[0031] FIG. 20 shows display of bulb mode exposure time for the
third embodiment of the invention, with FIG. 20(a) to FIG. 20(g)
showing change with lapse of cycle time.
[0032] FIG. 21 is a flowchart showing an exposure operation of a
fourth embodiment of the present invention.
[0033] FIG. 22 shows display of bulb mode exposure time for the
fourth embodiment of the invention, with FIG. 22(a) to FIG. 22(g)
showing change with lapse of cycle time.
[0034] FIG. 23 is an external perspective drawing looking at a
digital single lens reflex camera of a fifth embodiment of the
present invention from a rear surface.
[0035] FIG. 24 is a block diagram showing the overall structure of
electrical systems of a digital single lens reflex camera relating
to the fifth embodiment of the present invention.
[0036] FIG. 25 is a block diagram showing in abstract form the
structure relating to image forming and display in bulb mode etc.,
in a digital single lens reflex camera of the fifth embodiment of
the present invention.
[0037] FIG. 26 is a flowchart showing an exposure operation of a
fifth embodiment of the present invention.
[0038] FIG. 27 shows display of bulb mode exposure time for the
fifth embodiment of the invention, with FIG. 27(a) to FIG. 27(g)
showing change with lapse of cycle time.
[0039] FIG. 28 is a flowchart showing an exposure operation of a
sixth embodiment of the present invention.
[0040] FIG. 29 is a flowchart showing an exposure operation of a
seventh embodiment of the present invention.
[0041] FIG. 30 is a flowchart showing an exposure operation of an
eighth embodiment of the present invention.
[0042] FIG. 31 is a flowchart showing an exposure operation of the
eighth embodiment of the present invention.
[0043] FIG. 32 is a block diagram showing the overall structure of
electrical systems of a digital single lens reflex camera relating
to a ninth embodiment of the present invention.
[0044] FIG. 33 is a block diagram showing in abstract form the
structure relating to image forming and display in bulb mode etc.,
in a digital single lens reflex camera of the ninth embodiment of
the present invention.
[0045] FIG. 34 is a flowchart showing an exposure operation of the
ninth embodiment of the present invention.
[0046] FIG. 35 shows display of bulb mode exposure time for the
ninth embodiment of the invention, with FIG. 35(a) to FIG. 35(g)
showing change with lapse of cycle time.
[0047] FIG. 36 is a block diagram showing in abstract form the
structure relating to image forming and display in bulb mode etc.,
in a digital single lens reflex camera of a tenth embodiment of the
present invention.
[0048] FIG. 37 is a flowchart showing a shooting operation of the
tenth embodiment of the present invention.
[0049] FIG. 38 is a flowchart showing an exposure operation of the
tenth embodiment of the present invention.
[0050] FIG. 39 shows display of bulb mode exposure time for the
tenth embodiment of the invention, with FIG. 39(a) to FIG. 39(g)
showing change with lapse of cycle time.
[0051] FIG. 40A and FIG. 40B show list display of all added images
at the time of completion of bulb mode exposure with the tenth
embodiment of the present invention, with FIG. 10A being a list
display immediately after exposure completion, and FIG. 40B being
list display for a selected time.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0052] In the following, preferred embodiments using a digital
single lens reflex adopting the present invention will be described
using the drawings. FIG. 1 is an external perspective drawing of a
digital single lens reflex camera relating to a first embodiment of
the present invention seen from a rear surface.
[0053] This digital single lens reflex camera comprises a camera
body 200 and an interchangeable lens 100. A release button 21,
exposure mode dial 22, information setting dial 24, and strobe 50
etc. are arranged on the upper surface of the camera body 200. The
release button 21 has a first release switch that turns on if the
photographer presses the button down halfway, and a second release
switch that is turned on when the button is pressed down fully.
[0054] By turning this first release switch (hereafter called 1R)
on, the camera carries out exposure preparation operations such as
focal point detection, focusing of the photographing lens, and
metering for the subject brightness, and as a result of turning the
second switch (hereafter called 2R) on, the camera executes a
shooting operation to acquire image data for a subject image based
on output of the image sensor 221 (refer to FIG. 2).
[0055] The exposure mode dial 22 is an operation member constructed
capable of rotation, and by aligning a pictorial display or symbol
representing an exposure mode provided on the exposure mode dial 22
with an index, it is possible to select respective exposure modes,
such as program exposure mode (P), aperture priority exposure mode
(A), shutter speed priority exposure mode (S), manual exposure mode
(M), and bulb mode (B).
[0056] An information setting dial 24 is an operation member
constructed capable of rotation, and it is possible to select
desired setting values and modes etc. in an information display
screen or the like by rotational operation of the information
setting dial 24. If shutter speed priority exposure mode or manual
exposure mode are selected using the exposure mode dial 22, it is
possible to set a shutter speed using the information setting dial
24, and it is also possible to set to a long time of 30 seconds or
more. It is also possible to carry out setting of a cycle time for
image display during exposure at the time of bulb exposure or long
exposure time.
[0057] The strobe 50 is a pop-up type supplemental lighting unit,
and by operating an operating button, not shown, the strobe 50 pops
up and is capable of irradiating light to a subject.
[0058] A rear surface liquid crystal monitor 26, continuous/single
shot button 22, AE lock button 28, a cross-shaped button for up
30U, a cross-shaped button for down 30D, a cross-shaped button for
right 30R, a cross-shaped button for left 30L, (if these buttons
30U, 30D, 30R and 30L are referred to collectively, it will be
called a cross-shaped button 30), an OK button 31, a live view
display button 33, an enlarge button 34, a menu button 37 and a
playback button 38 are arranged on the rear surface of the camera
body 200.
[0059] The rear surface liquid crystal monitor 26 is a display unit
for carrying out live view display, playback display of a subject
images that have already been taken, and display of exposure
information and menus. Also, at the time of bulb exposure or long
time exposure etc. image display is carried out during the exposure
operation based on image signals acquired by the image sensor 221.
The monitor is not limited to a liquid crystal display as long as
it is possible to perform these display operation.
[0060] The continuous/single shot button 27 is an operation member
switching between continuous shooting mode where pictures are taken
continuously while the release button 21 is fully pressed down,
and, single shot mode where a single picture is taken if the
release button 21 is pressed down fully. The AE lock button 28 is
an operation member for fixing a metered value. After brightness of
an exposed image has been metered, if this AE lock button 28 is
operated the metered value is maintained even if the composition is
changed, and it is possible to take a picture without altering the
exposure level.
[0061] The cross-shaped button 30 is an operation member for
instructing movement of a cursor in two dimensional directions, the
X direction and Y direction, on the rear surface liquid crystal
display monitor 26, and is also used in selection commands for a
subject image, when performing playback display of subject images
that have been stored in the storage medium 277 etc. Besides
providing four buttons for up, down, left and right, it is also
possible to replace with an operating member capable of operation
in two dimensional directions, such as a touch switch
[0062] The OK button 31 is an operation member for confirming
various items selected by the cross-shaped button 30 and the
control dial 24 etc.
[0063] The live view display button 33 is an operating button for
switching to live view display from a display screen for
information display etch, or switching from live view display to a
display screen for information display etc. Live view display is a
mode that displays a subject image for viewing on the rear surface
liquid crystal monitor 26 based on output of the image sensor 221
for subject image storage, and information display is a mode for
displaying exposure information of the digital single lens reflex
camera on the rear surface liquid crystal monitor 26 for display
setting.
[0064] The enlargement button 34 is an operation member for
enlarging display of part of a subject image on the rear surface
liquid crystal monitor 26, and it is possible to change the
enlargement position by operation of the above-described
cross-shaped button 30.
[0065] The menu button 37 is an operation member for switching to
menu mode in order to set various modes of this digital single lens
reflex camera, and if menu mode is selected by operation of this
button 37 a menu screen is displayed on the rear surface liquid
crystal monitor 26. The menu screen is comprised of a multiple
hierarchical structure, and various items are selected using the
cross-shaped button 30 and selection is determined by operating the
OK button 31.
[0066] The playback button 38 is an operation button for
instructing display of subject images, that have been stored after
being taken, on the rear surface liquid crystal monitor 26. Image
data of subjects stored in a compressed mode such as JPEG, for
example, in SDRAM (Synchronous Dynamic Random Access Memory) 267
and a storage medium 277, that will be described later, is expanded
and displayed.
[0067] A storage medium housing cover 40 is attached to the side
surface of the camera body 200. If this storage medium cover 40 is
opened, a slot for fitting the storage medium 277 is provided
inside, and the storage medium 277 can be loaded into or removed
from the camera body 200.
[0068] Next, the overall structure principally involved in the
electrical systems of the digital single lens reflex camera will be
described using FIG. 2. With this embodiment, the interchangeable
lens 100 and the camera body 200 are constructed as separate
bodies, electrically connected by means of a communication contact
300, but it is also possible to integrally construct the
interchangeable lens 100 and the camera body 200. A circuit block
for the built-in strobe 50 is omitted from FIG. 2.
[0069] A photographing optical system 101 for focusing and focal
length adjustment, and an aperture 103 for adjusting aperture, are
arranged inside the interchangeable lens 100. The photographing
optical system lens 101 is driven by a lens drive mechanism 107,
while the aperture 103 is driven by the aperture drive mechanism
109.
[0070] The lens drive mechanism 107, and the aperture drive
mechanism 109 are respectively connected to a lens CPU 111, and
this lens CPU 111 is connected to a communication circuit 273 of
the camera body 200 by means of the communication contact 300. The
lens CPU 111 performs control inside of the interchangeable lens
100, controls the lens drive mechanism 107 to perform focusing and
zoom operations, and controls an aperture value by controlling the
aperture drive mechanism 109.
[0071] Also, the lens CPU 111 transmits lens specific information
such as maximum aperture value and focal length information of the
interchangeable lens 100, and focal length and focus position
information detected by the optical system positional detection
mechanism (not shown in the drawing) to the camera body 200.
[0072] Inside the camera body 200, a rotatable moving mirror 201 is
provided moving between a position inclined by 45 degrees with
respect to the lens optical axis for reflecting a subject image to
a viewfinder optical system (lowered position, subject image
viewing position), and a raised up position for guiding the subject
image to the image sensor 221 (raised position, retracted
position).
[0073] A focusing screen 205 for image forming the subject image is
arranged above the movable mirror 201, and a pentaprism 207 for
lateral inversion of the subject image is arranged above this
focusing screen 205.
[0074] An ocular lens (not shown) for viewing the subject image is
arranged at an outgoing side of this pentaprism 207 (the right side
in FIG. 2), and a photosensor 211 is arranged next to the ocular
lens at a position that does not obstruct viewing of the subject
image. This photosensor 211 is connected to a photometry processing
circuit 241, and output of the photosensor 211 is subjected to
processing such as amplification processing and analog-digital
conversion by this photometry processing circuit 241.
[0075] A half mirror is constructed close to the middle of the
movable mirror 201, and a sub-mirror 203 for reflecting the subject
image that has passed through the half mirror to a lower section of
the camera body 200 is provided on a rear surface of the movable
mirror 201.
[0076] This sub mirror 203 is capable of rotation with respect to
the movable mirror 201, and when the movable mirror 201 is raised
up (position shown by dotted lines in FIG. 2) the sub mirror 203
rotates to a position covering the half mirror part, while when the
movable mirror 201 is in a subject image viewing position (lowered
position) the sub-mirror 203 is at a position opened with respect
to the movable mirror 201, as shown in the drawing.
[0077] This movable mirror 201 is driven by a movable mirror drive
mechanism 239. Also, a focal point detection sensor 243 is arranged
below the sub-mirror 203, and output of this focal point detection
sensor 243 is connected to a focal point detection processing
circuit 245. The focal point detection sensor 243 measure defocus
amount for a subject image formed using the photographing optical
system 101, and is constructed of a well-known phase difference AF
optical system for separating peripheral light of the photographing
optical system 101 into two luminous fluxes, and a pair of
sensors.
[0078] A focal plane type shutter 213 for exposure time control is
arranged behind the movable mirror 201, and drive control for this
shutter 213 is performed by a shutter drive mechanism 237. An image
sensor 221 is arranged behind the shutter 213, and a subject image
formed by the photographing optical system 101 is photoelectrically
converted into electrical signals. It goes without saying that it
is possible to use CCD (Charge Coupled Devices), or a
two-dimensional fixed imaging element such as CMOS (Complementary
Metal Oxide Semiconductor) as the image sensor 211.
[0079] An infrared cut filter/low pass filter 217, which is an
optical filter for removing an infrared component and a high
frequency component from subject light flux, is arranged between
the shutter 213 and the image sensor 221. A temperature measurement
circuit 231 is also arranged close to the image sensor 221. This
temperature measurement circuit 231 measures ambient temperature
close to the image sensor 221 using temperature dependence of
forward current of a diode, and outputs a temperature signal
according to the ambient temperature.
[0080] The image sensor 221 is connected to an image sensor drive
circuit 223, and readout of image signals from the image sensor 221
etc. is performed by this image sensor drive circuit 223. The image
sensor drive circuit 223 is connected to an ADC (analogue to
Digital Converter) 225 for carrying out analogue to digital
conversion of an image signal.
[0081] Output of the ADC 225 is connected to a dark current
elimination circuit 227. The dark current elimination circuit 227
is a circuit for removing dark current generated by the image
sensor 221, and corrects image data that represents a subject using
dark current generated in a shielded region of a peripheral section
of the image sensor 221.
[0082] The dark current elimination circuit 227 is connected to
data bus 252 inside an ASIC (Application Specific Integrated
Circuit) 250. A sequence controller (hereafter referred to as a
body CPU) 251, image processing circuit 257, compression and
expansion circuit 259, video signal output circuit 261, SDRAM
control circuit 265, input/output circuit 271, communication
circuit 273, storage medium control circuit 275, flash memory
control circuit 279 and switch sensing circuit 283 are connected to
this data bus 252.
[0083] The body CPU 251 that is connected to the data bus 252
controls operation of this digital single lens reflex camera. The
image processing circuit 257 is connected to the data bus 252 and
carries out various image processing such as digital amplification
of digital image data (digital gain adjustment processing), color
correction, gamma (.gamma.) correction, contrast correction and
image generation for live view display etc.
[0084] Also, the compression and expansion circuit 259 is a circuit
for compressing image data stored in the SDRAM 267 using a
compression system such as JPEG, TIFF etc. and expanding compressed
image data. The image compression is not limited to JPEG and TIFF,
and it is also possible to apply other compression systems.
[0085] The video signal output circuit 261 is connected to the rear
surface liquid crystal monitor 26 via a liquid crystal monitor
drive circuit 263. The video signal output section 261 converts
image data stored in the SDRAM 267 or the storage medium 277 into
video signals for display on the rear surface liquid crystal
monitor 26. The rear surface liquid crystal monitor 26 is arranged
on the rear surface of the camera body 200 as shown in FIG. 1, but
as long as it is in a position that can be seen by the photographer
it is not limited to the rear surface, and also is not limited to
liquid crystal and can be another display device.
[0086] The SDRAM 267 is connected via the SDRAM control circuit 265
to the data bus 252, and this SDRAM 267 acts as a buffer memory for
temporarily storing image data that has been subjected to image
processing by the image processing circuit 257 or image data that
has been compressed by the compression and expansion circuit
259.
[0087] The input/output circuit 271 connected to the above
described image sensor drive circuit 223, temperature measurement
circuit 231, shutter drive mechanism 237, movable mirror drive
mechanism 239, photometry processing circuit 241, and focal point
detection processing circuit 245 controls input and output of data
to various circuits, such as the body CPU 251 via the data bus
252.
[0088] The communication circuit 273 that is connected to the lens
CPU 111 via the communication contact 300 is also connected to the
data bus 252, and carries out data exchange with the body CPU 251
etc. and communication for control commands. The storage medium
control circuit 275 connected to the data bus 252 is connected to
the storage medium 277, and performs control of storing image data
etc. to this storage medium 277 and reading out of image data
etc.
[0089] The storage medium 277 is constructed so that any rewritable
storage medium, such as xD picture card, (registered trademark),
Compact Flash (registered trademark), SD memory Card (registered
trademark) or memory stick (registered trademark) can be fitted,
and is removably inserted into the camera body 200. Besides, it is
also possible to have a configuration where it is possible to
connect to a hard disc via a communication connection point.
[0090] The flash memory control circuit 279 is connected to a flash
memory 281, and this flash memory 281 stores programs for
controlling operation of the digital single lens reflex camera, and
the body CPU 251 performs control of the digital single lens reflex
camera in accordance with the programs stored in the flash memory
281. Incidentally, the flash memory 281 is an electrically
rewritable non-volatile memory.
[0091] Various switches 285, including a 1R switch for detecting a
first stroke (half press) of the release button 21 and a 2R switch
for detecting a second stroke (full press) of the release button
21, a power switch, a menu switch linked to the menu button 37, a
dial switch linked to the exposure mode dial 22, a dial switch
linked to the information setting dial 24, and various switches
liked to other operating members, is connected to the data bus 252
via a switch detection circuit 283.
[0092] Next, the structure relating to image display during
exposure, in bulb exposure etc., will be described using FIG. 3.
The control section 297 is constructed of a body CPU 251 for
controlling the overall digital single lens reflex camera. When
using bulb exposure mode, the setting section 298 automatically
sets a cycle time for display in order to confirm progress of the
exposure (exposure level) based on manual operation using the
information setting dial 24 or exposure information etc.
[0093] The imaging section 291 includes the image sensor 221, image
sensor drive circuit 223, ADC circuit 225 and dark current
elimination circuit 227, and outputs image data based on image
signals. Output of the imaging section 291 is connected to the
adding processing section 294.
[0094] The adding processing section 294 performs adding processing
of images acquired every predetermined time during bulb exposure or
long time exposure, and generates added mage data. A temporary
storage section 293 is constructed using a temporary storage device
such as SDRAM 267, and temporarily stores image data that has been
added in the adding processing section 294, supplies already stored
added image data in accordance with control commands from the
control section 297 to the adding processing section 294, and once
more stores newly added image data.
[0095] The adding processing section 294 is constructed using a
body CPU 251 and an image processing circuit 257 etc., and in
accordance with control commands from the control section 297
carries out processing to add added image data that is already
stored in the temporary storage section 293 with newest image
data.
[0096] An added image storage section 295 is constructed using a
storage medium such as the previously described storage medium 277,
and reads out the most recent added image data that has been added
in the adding processing section 294 in accordance with control
commands from the control section 297, and stores this data.
[0097] The image display section 296 is made up of a rear surface
liquid crystal monitor 26 and a liquid crystal monitor drive
circuit 263 etc., and, every time added image data that has been
added by the adding processing section 294 is updated and stored in
the temporary storage section 293, reads out the data from the
temporary storage section 293 in accordance with control commands
from the control section 297 to display the added image data.
[0098] With this type of structure, first an operator sets a cycle
time by operating the setting section 298. The control section 297
performs control so that image data that has been acquired by the
imaging section 291 is sequentially added by the adding processing
section 294 every set cycle time, and this added image is displayed
on the image display section 296.
[0099] As shown in FIG. 12, this added image is a gradual
cumulative addition of image data, and initially is a dark image,
as shown in FIG. 12(a), but if the image gradually changes to a
brighter image, images are repeatedly cumulatively added a number
of times and it will become an image that seems over exposed, as
shown in FIG. 12(g).
[0100] Next, detailed operation of the digital single lens reflex
camera of a first embodiment of the present invention will be
described using the flowcharts shown in FIG. 4 to FIG. 7.
[0101] FIG. 4 shows a power on reset operation performed by the
body CPU 251 at the camera body 200 side. If a battery is fitted
into the camera body 200, this flow of operations starts, and it is
determined whether or not the power switch of the camera body 200
is on (#1).
[0102] When the result of determination is that the power switch is
off, a sleep state, which is a low power consumption state, is
entered (#3). In this sleep state, interrupt processing is carried
out only when the power switch is turned on, and processing for
power switch on is carried out in steps #5 and after. Until the
power switch is turned on, operations other than power switch
interrupt processing are suspended, and consumption of the power
supply battery is prevented. In the event that the power switch was
on in step #1, or the sleep state of step #3 is left, supply of
power commences (#5).
[0103] Next, if there is information such as exposure mode set by
the exposure mode dial 22, ISO speed set by the information setting
dial 24, or shutter speed or aperture value set manually, reading
in of these exposure conditions and lens information is carried out
(#7).
[0104] Reading of lens information in step #7 is the reading of
lens specific information, such as maximum aperture of the
interchangeable lens 100, and focal length information, from the
lens CPU 111 by means of the communication circuit 273. In this
step, in the event that bulb mode exposure has been set, or a long
time has been set as the shutter speed, these items of information
are read.
[0105] It is next determined whether or not bulb mode has been set
(#9). From the fact that the exposure mode is read in step #7, it
is determined whether or not bulb mode has been set as the read
exposure mode.
[0106] If the result of determination in step #7 is that bulb mode
has not been set, metering and exposure value calculation is
carried out (#11). In this step, subject brightness is then
measured by the photosensor 211, exposure amount is calculated, and
exposure control values such as shutter speed and aperture value
are calculated in accordance with exposure mode and exposure
conditions, using this exposure value.
[0107] If the result of determination in step #9 is that bulb mode
has been set, input of cycle time (cycle for repeatedly outputting
image data) is carried out (#31). Input of this cycle time will be
described later using FIG. 5. If input of cycle time is completed,
processing advances to step #13. In the case of bulb mode, since
opening and closing of the shutter 213 is carried out by user
operation and is not related to metering, the metering and exposure
value calculation of step #11 are not executed.
[0108] Next, the exposure information is displayed on the rear
surface liquid crystal monitor 26 (#13). As exposure information,
there are exposure mode and exposure conditions read in step #7 and
exposure control values for shutter speed and aperture value
calculated in #11. In the event that bulb mode has been set as the
exposure mode, then as shown in FIG. 10, a bulb mode display 301
and cycle time display 302 are displayed on the rear surface liquid
crystal monitor 26 together with other exposure information.
[0109] If display of exposure information is carried out, it is
next determined whether or not a playback switch linked to the
playback button 38 is on (#17). Playback mode is a mode for reading
out image data stored in the storage medium 277 and displaying them
on the rear surface liquid crystal monitor 26, when the playback
button 38 has been operated. If the result of determination is that
the playback switch is on, a playback operation is executed
(#33).
[0110] If the result of determination in step #17 is that the
playback switch is not on, it is determined whether or not the menu
switch that links to the menu button 37 is on (#19). In this step,
it is determined whether or not the menu button 37 has been
operated and the menu mode has been set. If the result of
determination is that the menu switch is on, menu display is
performed on the rear surface liquid crystal monitor 26, and a menu
setting operation is carried out (#35). Various setting operations
such as AF mode, white balance, ISO speed setting, drive mode
setting etc. can be carried out by the menu setting operation.
[0111] If the determination result in step #19 is that the menu
switch is not on, it is next determined whether or not the release
button 21 has been pressed down halfway, that is, whether or not
the 1R switch is on. If the result of determination is that the 1R
switch is on, a shooting operation sub-routine is executed to carry
out exposure preparation and shooting (#37). This sub-routine will
be described in detail later using FIG. 6.
[0112] If the result of determination in step #21 is that the 1R
switch is not on, then similarly to step #1 it is determined
whether or not the power switch is on (#23). If the result of
determination is that the power switch is on, processing returns to
step #7 and the operations described above are repeated. On the
other hand, if the power switch is not on, supply of power is
stopped (#25), and processing returns to step #3 where the
previously described sleep state is entered.
[0113] Next, the input operation for cycle time of step #31 will be
described using FIG. 5. If this subroutine is entered, ambient
temperature close to the image sensor 221 that has been measured by
the temperature measurement circuit 231 is first detected (#41). If
the ambient temperature is obtained, determination of an upper
limit value for cycle time is carried out based on this ambient
temperature (#43).
[0114] As is shown conceptually in FIG. 8, photodiodes (pixels) are
arrayed in two dimensional directions on the image sensor 221. In
FIG. 8, each square represents a pixel. A majority of the pixels of
the image sensor 221 are the effective pixel region 311, with the
right side constituting a horizontally shielded pixel region 312
and the lower side constituting a vertically shielded pixel region
313. Image data is generated based on pixel signals output from
pixels belonging to the effective pixel region 311, while dark
current data is generated based on pixel signals output from pixels
belonging to the horizontally shielded pixel region 312 and the
vertically shielded pixel region 313.
[0115] As shown in FIG. 9, this dark current has a temperature
dependent characteristic, and as the temperature close to the image
sensor 221 become hot, the dark current (integrated value) also
rapidly becomes large as time passes. Dark current is superimposed
on the pixel signals of the subject image output from the image
sensor 221 that have been photoelectrically converted, and if
exposure time (integration time) becomes long the dark current can
no longer be ignored. Dark current output from the horizontally
shielded pixel region 312 and the vertically shielded pixel region
313 is also assumed to be generated in the effective pixel region
311, and in the dark current elimination circuit 227 dark current
correction is carried out by deducting dark current data from image
data based on the pixel signals.
[0116] The dark current quickly reaches saturation level as the
temperature becomes high. If the dark current reaches saturation
level, it will not be possible to correctly perform dark current
elimination. In this embodiment therefore, in the event that an
exposure operation is carried out over a long time, such as bulb
mode, pixel signals are read from the image sensor 221 before the
dark current reaches saturation level. Specifically, taking into
consideration the dark current characteristic, the upper limit
value for cycle time is controlled based on ambient temperature
measured by the temperature measuring circuit 231 so that dark
current does not saturate (#43). Specifically, a table for ambient
temperature and upper limit value is stored, and determination is
made by referring to this table.
[0117] Next, in order to input cycle time, it is determined whether
or not the information setting dial 24 has been operated (#45). If
the result of determination is that the information setting dial 24
has not been operated, the original routine is returned to. On the
other hand, if the information setting dial 24 has been operated
the switch detection circuit 283 detects direction of rotation of
the dial (#47).
[0118] It is next determined whether or not the detection direction
of rotation is a direction that causes a reduction in cycle time
(#49). If the result of determination is that the rotation
direction causes a reduction in cycle time, it is determined
whether or not the previous cycle time has reached a lower limit
value (#51). The lower limit value should be set appropriately, but
can be, for example, about 0.1 seconds. If the result of
determination is that the lower limit value has not been reached,
the cycle time is successively shortened in predetermined steps
from the currently set state (#53).
[0119] As shown in FIG. 10, the cycle time is displayed as a cycle
time display 302 within exposure information on the rear surface
liquid crystal monitor 26. Every time there is a rotation operation
using the information setting dial 24 in a direction to shorten the
cycle time, for example, if the currently set state is an initial
value of 30 second, there is a gradual reduction in predetermined
steps from FIG. 11(c) towards the lower limit value of FIG. 11(a).
The predetermined step should be appropriately set taking into
consideration ease of use. Once cycle time shortening is finished,
the original routine is returned to.
[0120] If the result of determination in step #49 is that the
rotation direction is not such as to reduce cycle time, then it is
determined whether or not the previous cycle time has reached the
upper limit value determined in step #43 (#55). If the result of
determination is that the upper limit value has not been reached,
the cycle time is successively extended in predetermined steps
(#57). Every time there is a rotation operation using the
information setting dial 24 in a direction to increase the cycle
time, there is a gradual increase, in predetermined steps, from the
current state towards the upper limit value of FIG. 11(e). The
cycle time intervals of FIG. 11(a) to (e) are only one example, and
can be appropriately changed.
[0121] Next, the shooting operation of step #37 will be described
using FIG. 6. This subroutine is started if the 1R switch is turned
on, and the first thing to happen is that exposure information
being displayed on the rear surface liquid crystal monitor 26 is
turned off (#61). Next, a phase difference AF subroutine is
executed (#63). In this subroutine, defocus direction and defocus
amount of the photographing system 101 are detected using
well-known phase difference AF, drive control for the optical
system drive mechanism 107 is carried out based on this defocus
direction and defocus amount, and focusing of the photographing
optical system 101 is carried out.
[0122] If phase difference AF is completed, then similarly to step
#9 it is determined whether or not bulb mode has been set (#65). If
the result of determination is that bulb mode has not been set,
metering and exposure value calculation are carried out, and
exposure control values such as shutter speed and aperture value
are obtained (#67).
[0123] On the other hand, if the result of determination in step
#65 is that bulb mode has been set, step #67 is skipped and
processing advances to step #69. In the case of bulb mode, as
described previously, the time for opening and closing the shutter
213 is determined by the photographer, and metering and exposure
value calculation are not required.
[0124] Next it is determined whether or not the shutter button 21
has been pressed down fully, that is, if the 2R switch is on (#69).
If the result of determination is that the 2R switch is not on, it
is then determined whether or not the 1R switch is on (#87). If the
result of determination is that the 1R switch is not on, the
shooting operation is terminated and the original routine is
returned to. On the other hand, if the result of determination is
that the 1R switch is on, step #69 is returned to, and a standby
state is entered where the states of the 1R switch and the 2R
switch are alternately detected.
[0125] If the result of determination in step #69 is that the 2R
switch is on, processing transfers to a step for performing
exposure. First a retraction operation for the movable mirror 201
(moving to the raised position) is carried out (#71). As a result,
subject light flux is guided to the image sensor 221 by the
photographing optical system 101. Next, a stopping down operation
is instructed to the lens CPU 111 and a stopping down operation for
the aperture 103 is carried out (#73).
[0126] As a result, it is possible to prepare entry to the normal
exposure operation or the bulb exposure operation, and so an
exposure operation is started (#75). Exposure is the starting of
travel of the front curtain of the shutter 213, together with
charge accumulation of the image sensor 221. If a time
corresponding to the shutter speed acquired in step #67 or a
shutter speed that was manually set by the photographer has
elapsed, or if bulb exposure completion has been instructed by the
photographer, travel of the rear curtain of the shutter 213 starts,
and charge accumulation of the image sensor 221 is terminated.
[0127] At the time of this exposure operation, if bulb mode has
been set, then while the release button 21 is being pressed down
completely the shutter 213 is open, and at this time image data is
repeatedly acquired using the image sensor 221 at intervals of the
cycle time, and an image is displayed on the rear surface liquid
crystal monitor 26 while being updated, based on this image data.
This exposure will be described in detail later using FIG. 7.
[0128] If the exposure operation is completed, an instruction to
open up the aperture 103 is output to the CPU 111, and the aperture
103 is opened up (#77). Then, the movable mirror 201 is restored to
the lowered position (#79), and image processing is carried out for
a normal image that is read out from the image sensor 221 and
temporarily stored in the SDRAM 267 or added image data (#81).
Image data that has been image processed is stored in the storage
medium 277 (#83), and display of the image that was being displayed
on the rear surface liquid crustal monitor is stopped (#85). Once
image display 26 is stopped, the original routine is returned
to.
[0129] Next, the exposure operation of step #75 will be described
using FIG. 7. If this subroutine is entered, first, similarly to
step #9, it is determined whether or not bulb mode has been set
(#101). If the result of determination is that bulb mode has not
been set, normal exposure mode, such as program exposure mode, is
executed.
[0130] As the normal exposure mode, first a timer for exposure time
timing is started (#103), and together with opening of the shutter
213 exposure to the image sensor 221 is commenced (#105). That is,
photoelectric conversion of a subject image formed on the image
sensor 221 is carried out, and accumulation of signal charge is
commenced.
[0131] If exposure is started, it is next determined whether or not
an exposure time (set time) corresponding to a shutter speed
calculated in step #67 or set manually has elapsed (#107). If the
result of determination is that the exposure time has elapsed,
imaging on the image sensor 221 is stopped together with closing of
the shutter 213 (#109).
[0132] Next, reading of image signals from the image sensor 221 is
carried out (#111), and the read out image signals are temporarily
stored in the SDRAM 267 (#113). Display of an exposed image is
carried out on the rear surface liquid crystal monitor 26 based on
the temporarily stored image signals (#115).
[0133] If the result of determination in step #101 is that bulb
mode has been set, first of all data of the added image storage
region (not shown) allocated inside the temporary storage section
293 is cleared (#120), a timer for display cycle time timing is
started (#121), and similarly to step #105 imaging is commenced
with the opening of the shutter 213 (#123). Next, it is determined
whether or not the timer for cycle time timing has reached the
cycle time set in step #31 (#125).
[0134] If the result of determination in step #125 is that the
cycle time has not elapsed, it is determined whether or not the
full pressing of the release button 21 has been released, that is,
whether or not the 2R switch is off (#151). In the event that the
2R switch is on and the cycle time has not elapsed, a standby state
is entered where the determinations at steps #125 and #151 are
alternately executed.
[0135] If the result of determination in step #125 is that the
cycle time has elapsed, image forming of the image sensor 221 is
stopped with the shutter 213 still open, and reading of image
signals is carried out (#127, #129). Image data resulting from
digitalization of the read image signals is temporarily held in a
newest image saving region inside the storage region of the
temporary storage section 293 (#131). This holding of the data is
temporary saving for the adding processing of read image data that
will be executed later.
[0136] Next, the timer for cycle time timing is restarted (#133),
and imaging on the image sensor 221 is commenced (#135). Following
on, previously added image data stored in the added image storage
region of the temporary storage section 293, and the above
described newest image data, are added by the adding processing
section 294. The result of adding processing is again stored in the
added image storage region of the temporary storage section 293
(#137) and this stored added image is displayed on the rear surface
liquid crystal monitor 26 (#139). If the added image is displayed,
step #125 is returned to, and the previously described steps are
executed.
[0137] If the photographer looking at the displayed image decides
that the exposure level has reached an intended level, and full
pressing of the release button 21 is released, that is, if the 2R
switch is turned off, in accordance with the determination of step
#151 processing advances from step #151 to step #153, and a
transfer is made to processing for completion of the exposure
operation.
[0138] That is, similarly to steps #109, #111 and #113, imaging
stops together with closing of the shutter 213, image date is read
out, and temporary holding of image data is carried out (#153,
#155, #157). Then, similarly to steps #137 to #139, an added mage
resulting from addition processing is acquired, and this added
image is displayed after being stored (#159, #160, #161). Once the
added image is displayed, the original routine is returned to.
[0139] In this way, every time the cycle time set in step #31
elapses (Y in step #125) imaging by the image sensor 221 is
stopped, image signals are read in, added to already added image
data stored in the temporary storage section and, as shown in FIG.
12, displayed on the rear surface liquid crystal monitor 26. At the
point in time when the cycle time initially elapses, since cycle
time is short a completely dark image results, and the image is
gradually made brighter by adding image data each time the cycle
time elapses. The photographer can determine whether or not an
intended brightness has been reached by observing the rear surface
liquid crystal monitor 26.
[0140] With this embodiment, if bulb mode has been set the imaging
operation is repeated at intervals of the cycle time during the
exposure operation, and image data is stored in the temporary
storage section 293 every time the imaging operation is carried
out, and an added image resulting from adding the stored image data
is displayed on the rear surface liquid crystal monitor 26. This
cycle time can be manually set using the setting section 298, and
can be appropriately changed. It is therefore possible to carry out
display updating at an effective timing according to the exposure
conditions of the photographer's intentions.
[0141] Also in this embodiment, the cycle time is controlled to a
set value so that an upper limit value and a lower limit value are
not exceeded. As a result, it is possible to prevent use that
exceeds the performance of the image sensor 221. Further, in this
embodiment, the upper limit of the cycle time is varied in
accordance with a dark current characteristic. This means that it
is possible to carry out correction of image data in accordance
with the dark current, and it is possible to give an image with
less noise.
[0142] Next, a second embodiment of the present invention will be
described using FIG. 13 to FIG. 15. With the first embodiment, the
cycle time was manually set, but with the second embodiment the
cycle time is automatically changed according to subject
brightness. Also, imaging and image display are also repeatedly
executed at intervals of the cycle time for the case of long time
exposure.
[0143] The structure of the second embodiment is substantially the
same as the structure of the first embodiment shown in FIG. 1 to
FIG. 3, and the flowcharts shown in FIG. 4 to FIG. 7 are simply
changed to the flowcharts shown in FIG. 13 to FIG. 15, with
description centering on points of difference. The setting unit 298
of FIG. 3 is not manually set using the information setting dial 24
in the second embodiment, but is automatically set by the body CPU
251 etc.
[0144] FIG. 13 shows a power on reset operation performed by the
body CPU 251 at the camera body 200 side. This flowchart has the
same flow as the flowchart for power on reset shown in FIG. 4,
except that the subroutine for cycle time input of step #31 is
omitted, and so the same reference numerals will be used for the
same steps, and detailed description will be omitted.
[0145] In the first embodiment, the cycle time input subroutine of
step #31 was executed in order to manually set cycle time, but in
the second embodiment the cycle time is automatically set based on
subject brightness etc. and so step #31 is omitted. The shooting
operation subroutine of step #37 is the same as the flowchart of
FIG. 6 for the first embodiment.
[0146] Next, an exposure operation of step #75 within the
sub-routine for the shooting operation of step #37 will be
described using FIG. 14. If this exposure operation subroutine is
entered, it is determined whether or not the exposure mode is bulb
mode (#101). If the result of determination is that it is not bulb
mode, it is then determined whether or not it is a long time
exposure (#102). Regarding whether or not it is a long time
exposure, a long time exposure is determined if the shutter speed
read in step #7 exceeds 30 second for example.
[0147] If the result of determination is that it is not a long time
exposure, normal exposure is carried out. This normal exposure
operation is the same as from step #103 to step #115 of FIG. 7, and
the same steps have the same reference numerals, with detailed
description thereof being omitted.
[0148] If the result of determination in step #101 is that bulb
mode has been set, 0.5 seconds, for example, is set as an initial
value for the cycle time (#118). Also, if the result of
determination in step #102 is that a long exposure time has been
set, the cycle time is set according to the set shutter speed
(#117). As setting of the cycle time here, the cycle time is made
1/100th of the set shutter speed, for example.
[0149] If setting of cycle time is carried out in step #117 or step
#118, then next the added image storage region of the temporary
storage section 293 is cleared (#120), a timer for cycle time
timing is started (#121), and imaging on the image sensor 221 is
commenced (#123).
[0150] It is then determined whether or not the time of the time
for cycle time timing has reached the set cycle time (#125). If the
result of determination is that the cycle time has not elapsed, it
is determined whether completion of bulb exposure has been
instructed (that is, whether full pressing of the release button 21
has been released and the 2R switch turned off) (#151).
[0151] If the result of determination in step #151 is that the 2R
switch is still on, it is determined whether the time set by the
long time exposure has elapsed (#152). If the result of
determination is that the set time has not elapsed, step #125 is
returned to. In this way, in the case where the 2R switch is still
on with both the cycle time and the set long time not elapsed, a
standby state is entered where the determinations of steps #125,
#151 and #152 are repeated.
[0152] If the result of determination in step #125 is that the
cycle time has elapsed, then similarly to from step #127 to #139 in
FIG. 7, image forming of the image sensor 221 is stopped with the
shutter 213 still open (#127), and reading of pixel signals is
carried out (#129).
[0153] Next, image data based on the read out pixel signals is
temporarily stored in the temporary storage section 293 (#131), and
after the timer for cycle time timing is restarted (#133) imaging
is commenced (#135). Addition of temporarily stored image data and
previously added image data is then carried out (#137), and this
added image is stored again in the added image storage region of
the temporary storage section 293 (#138), and then displayed
(#139).
[0154] In this way, every time it is determined in step #125 that
the cycle time has elapsed, similarly to the case of the first
embodiment, together with reading of pixel signals from the image
sensor 221, image data based on the image signals is stored in a
storage region of the temporary storage section 293, and an overall
added image is generated and displayed.
[0155] If display of the added image is carried out, next,
similarly to step #102, it is determined whether or not there is a
long time exposure (#141). If the result of determination is that
there is a long time exposure, processing returns to step #125 and
the operations described above are executed. On the other hand, if
there is not a long time exposure, that is, in the event that bulb
mode has been set, resetting of the cycle time is carried out
(#143).
[0156] Cycle time when bulb mode has been set is set at an initial
value in step #118, but this cycle time is subjected to automatic
adjustment in step #143 so that cycle time is shortened when
subject brightness is high, or extended when subject brightness is
low. A subroutine for resetting of this cycle time will be
described later using FIG. 15. Once resetting of cycle time has
been carried out step #125 is returned to.
[0157] If the result of determination in step #151 is that there is
a bulb exposure completion instruction, or if the result of
determination in step #152 is that the set time has elapsed,
processing for completing the exposure operation is carried out in
steps #153 to #161. These steps are the same as FIG. 7, and the
same steps have the same reference numerals, with detailed
description thereof being omitted.
[0158] Next, a subroutine for resetting cycle time in step #143
will be described using FIG. 15. If this subroutine for resetting
cycle time is entered, determination of brightness level is carried
out (#181). As the brightness level, an average brightness of image
data read out in step #129 is used. Generally, if brightness of
each pixel of image data has an 8-bit resolution, the brightness
level of each pixel is from 0 to 255. Average brightness is an
average of those brightness levels for each pixel. Besides average
brightness, it is also possible to appropriately use other metered
calculations, such center-weighted brightness.
[0159] Using the obtained brightness level, prediction of exposure
time is then carried out (#183) until correct exposure is attained.
Here, correct exposure assumes the case where average of brightness
level of each pixel is, for example, about 140. Accordingly, if the
current average brightness level and the time taken to reach that
brightness level are known, it is possible to estimate the time
taken to attain correct exposure. If estimated time is obtained,
calculation of cycle time is next carried out (#185).
[0160] As this calculation, for example, similarly to step #117,
the estimated time is divided by 100. Cycle time is update based on
the time obtained here (#187), and the original routine is returned
to. If the processing flow for the exposure operation shown in FIG.
14 is returned to, in step #125 determination is made using the
re-set cycle time, and imaging and display are carried out at this
time interval.
[0161] In this way, in the second embodiment of the present
invention, when in bulb mode it is possible to automatically re-set
the cycle time according to subject brightness. It is therefore
possible to carry out display updating at an effective timing
according to subject brightness. Also, with a long exposure time,
cycle time is automatically set according to the set time. It is
therefore possible to carry out display updating at an effective
timing according to the set time.
[0162] The set cycle time in steps #117 and step #120 are only
examples, and can be appropriately changed. Also, with respect to
the determination as to whether or not there is a long time
exposure in step #102, the determination value for whether or not
there is a long time can also be appropriately changed. Further,
regarding setting of the cycle time in step #117, besides setting
the cycle time simply by division, it is also possible to adopt
various methods, such as, for example, dividing the long time into
zones, and determining a set time for each zone.
[0163] In the first and second embodiments of the present
invention, in the case of exposure in bulb mode or over a long
time, the imaging section 291 is repeatedly operated at intervals
of the cycle time, image data repeatedly output from the imaging
section 291 is sequentially added, added image data is generated,
and image display is carried out based on this added image data.
The cycle time is set either manually or automatically. It is
therefore possible to perform display update at an effective
timing, and it is possible for the photographer to confirm the
appearance of the shot as imaging progresses in bulb mode or over a
long time.
[0164] Next, a third embodiment of the present invention will be
described using FIG. 16 to FIG. 20. In the first and second
embodiments, an added image was displayed from the start. However,
for a short while after commencing exposure the screen will remain
black and the photographer is unable to confirm whether or not
exposure is being carried out, and may feel uneasy. With the third
embodiment, in order to make it possible for the photographer to
confirm that the exposure is in progress even in a period where the
brightness level of a subject image immediately after starting the
exposure is low, a notification display is carried out to show that
bulb exposure etc. is in progress.
[0165] The structure of the third embodiment is partially similar
to the structure of the first embodiment, and so parts of the
structure that are the same will have detailed description
omitted.
[0166] The external appearance of a digital single lens reflex
camera of the third embodiment of the present invention is the same
as in FIG. 1. Electrical circuits of this digital single lens
reflex camera are shown in FIG. 16. Compared to the electrical
circuits of the first embodiment (refer to FIG. 2), the third
embodiment differs only in that the temperature measurement circuit
231 has been omitted. This is because in this embodiment, the
function of determining an upper limit for cycle time according to
surrounding temperature is omitted. In this embodiment also, it is
obviously also possible to determine an upper limit of cycle time
according to surrounding temperature, similarly to the first and
second embodiments.
[0167] FIG. 17 shows a structure relating to image display during
exposure, for bulb exposure. Compared to the first embodiment
(refer to FIG. 3) there is a difference in that the setting section
298 is omitted. Naturally, the setting section 298 is also provided
in the third embodiment, but as it is not important it has been
omitted from FIG. 17.
[0168] With this type of arrangement, the control section 297
performs control so that image data that has been acquired by the
imaging section 291 is sequentially added by the adding processing
section 294 every set cycle time, and this added image is displayed
on the image display section 296. Display by the rear surface
liquid crystal monitor 26 at the time of bulb exposure involves
first displaying notification information 320a at the time of
starting bulb exposure (FIG. 20(a)), and displaying only
notification information 320b within a specified period after that
(FIG. 20(b)).
[0169] Also, image data is cumulatively added from the start of
exposure, and an added image for bulb exposure is displayed once a
specified brightness level has been reached, as shown in FIG.
20(c). At the stage of FIG. 20(c) the exposure time is insufficient
and so the image is dark, but after that if the image gradually
changes to a brighter image and images are repeatedly cumulatively
added a number of times, it will become an image that appears over
exposed, as shown in FIG. 20(g). The notification information 320c
to 320g is also displayed in a superimposed manner during display
of the added images. If this notification information 320c to 320g
is also present during execution of bulb exposure, the elapsed time
for the bulb exposure is displayed.
[0170] Next, detailed operation of the digital single lens reflex
camera of the third embodiment of the present invention will be
described using the flowcharts shown in FIG. 18 and FIG. 19. In the
third embodiment also, if a battery is fitted, the processing flow
for power on reset is executed. The processing flow for this power
on reset is the same as in FIG. 4 for the first embodiment, and so
detailed description will be omitted.
[0171] Processing flow for the cycle time input of step #31 in the
processing flow of the power on reset (refer to FIG. 4) will be
described using FIG. 18. The processing flow for this cycle time
input differs from the processing flow of the cycle time input of
the first embodiment (refer to FIG. 5) only in that step #41
(temperature detection) and step #43 (determination of cycle time
upper limit value) are omitted. As described above, with this
embodiment the temperature measurement circuit 231 is omitted,
which means that steps #41 and #43 are omitted from the processing
flow for cycle time input.
[0172] With this embodiment, the determination as to whether or not
the cycle time has reached an upper limit at step #55 can be
appropriately set, but it is possible, for example, to make 9
minutes a length of time that will not be affected by dark current.
Apart from this, it is the same as the processing flow (FIG. 5) for
cycle time input of embodiment one, and so detailed description
will be omitted.
[0173] Next, the shooting operation of step #37 in the processing
flow of the power on reset (refer to FIG. 4) is the same as the
processing flow of the shooting operation in the first embodiment
(refer to FIG. 6) and so detailed description is omitted.
[0174] Next, the exposure operation of step #75 in the processing
flow for the shooting operation will be described using FIG. 19. In
the description, steps carrying out the same processing as the flow
of FIG. 7 for the first embodiment have the same step numbers
attached, and detailed description thereof is omitted.
[0175] If the exposure operation processing flow is entered, it is
first determined whether or not bulb mode has been set (#101). If
the result of this determination is that bulb mode has not been
set, normal exposure mode, such as program exposure mode, is
executed in steps #103 to #115. This normal exposure mode
processing is the same as for the flow of FIG. 7, and so detailed
description is omitted.
[0176] If the result of determination in step #101 is that bulb
mode has been set, then first the added image storage region that
has been allocated inside the temporary storage section 293 is
cleared (#119), and the cycle time that was manually input in step
#31 is set (#120A). Next, a timer for display cycle time timing is
started (#121), and similarly to step #105, together with opening
of the shutter 213 imaging is commenced (#123).
[0177] Display of notification information such as is shown in FIG.
20(a) is then started (#124). That is, at the time bulb exposure
commences, the screen is jet black, and if there is no display at
all the photographer will be unsure as to whether or not the
exposure using bulb exposure has started. In this embodiment
therefore, by displaying the notification information 320a it is
possible for the photographer to recognize that the exposure has
started.
[0178] If the display of notification information has started, it
is first determined whether or not the timer for cycle time timing
has reached the cycle time set in step #120A (#125). If the result
of determination is that the cycle time has not elapsed, it is
determined whether or not the full pressing of the release button
21 has been released, that is, whether or not the 2R switch is off
(#151). In the event that the 2R switch is on and the cycle time
has not elapsed, a standby state is entered where the
determinations at steps #125 and #151 are alternately executed.
[0179] If the result of determination in step #125 is that the
cycle time has elapsed, then similarly to step #109 and step #111,
image forming of the image sensor 221 is stopped with the shutter
213 still open, and reading of pixel signals is carried out (#127,
#129).
[0180] Next 1 is added to the update counter (#130A). The update
counter is reset at the same time as the timer is started in step
#121, and every time this step #130A is passed through 1 is added.
By multiplying a count value of this update counter by the cycle
time set in step #120A, it is possible to obtain a cumulative time
from when the exposure using bulb exposure started.
[0181] Next, the timer for cycle time timing is restarted (#131A),
and imaging on the image sensor 221 is commenced (#133A).
[0182] Next, added image data is read from a storage region that
was previously stored in the storage region of the temporary
storage section 293 and adding processing for this image data and
image data read out in step #129 is carried out (#135A). Image data
of the added image obtained here is stored in a storage region of
the temporary storage region 293 that is used for added image
storage (#137A).
[0183] If accumulation of added images is completed, determination
of brightness level is then carried out (#139A). The brightness
level is determined based on image data read out in step #129. In
this embodiment, since pixel signals are digitalized at a
resolution of 8-bits, it is possible for the charge accumulation
amount for each pixel to be expressed by a number from 0-255. This
charge accumulation amount corresponds to the subject brightness
level corresponding to that pixel, which means that if an average
value for all pixels is obtained a brightness level for image data
is obtained.
[0184] Next, it is determined whether or not the brightness level
obtained in step #139A has reached a predetermined brightness level
(#141A). In this embodiment the specified brightness level is made
20. The specified brightness level can obviously be appropriately
varied according to how the added image display appears.
[0185] If the result of determination in step #141A is that the
predetermined brightness level has not been reached, the
notification information 320b, as shown in FIG. 20(b) is displayed
(#147A). At this stage, the exposure amount from bulb exposure is
insufficient, and it can be considered that even if the added image
is displayed the screen will be unintelligible, and so, as shown in
FIG. 20(b), the fact that bulb exposure is in progress and an
elapsed time from the start of bulb exposure, are displayed.
[0186] This elapsed time is calculated based on a count value of
the update counter obtained in step #130A, and set cycle time. If
the display of notification information 320b is carried out, step
#125 is returned to, and the previously described operations are
executed. There is also no problem in providing a counter for
obtaining cumulative exposure time when using bulb exposure, and
displaying elapsed time based on this counter.
[0187] If the result of determination in step #141A is that the
predetermined brightness level has been reached, an added image
that has been added in step #135A is displayed (#143A).
Specifically, by executing from step #125 to step #147A once or a
plurality of times, the brightness level of the added image
improves. If the result of determination is that the brightness
level has reached the predetermined level, then since the image
from bulb exposure has reached a level at which it can be
displayed, an added image is displayed on the rear surface liquid
crystal monitor 26.
[0188] The notification information 320c to 320g, as shown in FIG.
20(c) to FIG. 20(g), is displayed superimposed on the added image
(#145A). The notification information 320c to 320g here is display
of the fact that there is a bulb exposure, together with the
elapsed time from commencement of the bulb exposure. The added
image and the notification information continue to be displayed
until the next cycle time has elapsed. If display is carried out,
step #125 is returned to, and the previously described steps are
executed.
[0189] If the result of determination in step #151 is that the full
pressing of the release button 21 has been released, that is, it
has been determined that the 2R switch has been turned off, then
similarly to step #127 imaging is stopped together with closing of
the shutter 213 (#153). Specifically, the exposure operation is
completed, and after that the original routine is returned to.
[0190] In this way, imaging by the image sensor 221 is stopped and
image data output every time the cycle time that was set in step
#31 (#120A) elapses (Y at #125). Addition processing for this image
data and the previous added image being stored in the storage
region of the temporary storage section 293 is carried out, and the
result is stored in the storage region of the temporary storage
section 293. The added image stored in each storage region is
updated and displayed in the rear surface liquid crystal monitor 26
every time the cycle time elapses, as shown in FIG. 20. At the
initial stages of exposure, since exposure amount is small an added
image is not displayed. After that, by cumulatively adding image
data every time the cycle time elapses, the image gradually becomes
brighter. If image brightness reaches a predetermined level, an
added image is displayed from then on.
[0191] Also, in this embodiment if bulb mode has been set, at the
time of starting an exposure using bulb exposure an image acquired
from the image sensor 221 is not displayed, and instead
notification information 320a, 320b indicating that bulb exposure
is in progress is displayed. It is therefore possible for the
photographer to easily recognize that the exposure operation is
progressing, even in a period where the brightness level of the
image after exposure has started is low.
[0192] Further, in this embodiment, the fact that the elapsed time
since the start of bulb exposure is displayed is extremely
useful.
[0193] Next, a fourth embodiment of the present invention will be
described using FIG. 21 and FIG. 22. In the third embodiment, if
the added image reaches a predetermined brightness level display of
the added image is carried out, but with the fourth embodiment only
the notification display 321a is displayed until an initial cycle
time elapsed, and if the initial cycle time elapses and an image is
read, the image is displayed.
[0194] The structure of the fourth embodiment is the same as that
of the third embodiment, the flowcharts shown in FIG. 4, FIG. 6,
and FIG. 18 are also the same, and the exposure information display
shown in FIG. 10 and the cycle time display shown in FIG. 11 are
also the same. The point of difference is that the flowchart
showing the exposure operation shown in FIG. 19 is replaced with
the flowchart in FIG. 21, and description will center on this
difference. Each of the steps within the flowchart shown in FIG. 21
that are the same as the steps in the flowchart shown in FIG. 19
have the same reference numerals attached, and detailed description
thereof is omitted.
[0195] If the processing flow for the exposure operation is
entered, it is determined whether or not it is bulb mode (#101),
and in the event that bulb mode has not been set, then similarly to
the third embodiment shown in FIG. 19, a normal exposure mode, such
as program exposure mode, is carried out. On the other hand, if
bulb mode has been set, then similarly to the third embodiment from
step #119 to step #123 is executed. Next, notification display for
bulb exposure is carried out (#124a). This notification display can
be the same display as in FIG. 20(a), but in this embodiment
notification display 321a as shown in FIG. 22(a) is carried
out.
[0196] If the notification display 321a for bulb exposure is
carried out, it is next determined whether or not the cycle time
has elapsed (#125). If the result of determination is that the
cycle time has not elapsed, then similarly to the third embodiment
a state is entered where the determinations at steps #125 and #151
are alternately executed. On the other hand, if the cycle time has
elapsed, then similarly to the third embodiment from step #127 to
step #137A are executed.
[0197] After that, in the third embodiment determination of the
brightness level of the added image etc. was carried out, but with
this embodiment display of the added image is carried out
regardless of the brightness level (#143A). Specifically, since the
cycle time has elapsed and reading of an image from the image
sensor 221 is carried out, this read image is displayed
immediately. The notification information 321b and 320c to 320g, as
shown in FIG. 22(b) to FIG. 22(g), is then displayed superimposed
on the added image (#145A).
[0198] If the added image and the notification information 321b and
320c to 320g is displayed, step #125 is returned to, the previously
described operations are executed, and similarly to the first
embodiment the added image and the notification displays 321b and
321c to 320g are updated and displayed every time the cycle time
elapses.
[0199] If the 2R switch is turned off, then as with the third
embodiment the shutter is closed, the imaging operation is stopped,
and the original routine is returned to.
[0200] In this way, with the fourth embodiment of the present
invention a predetermined period from start of the bulb exposure
displays that the bulb exposure is being executed. It is therefore
possible for the photographer to easily recognize that the exposure
is being carried out immediately after commencement of bulb
exposure. Also, if an image is read out after the initial cycle
time has elapsed, the acquired image is immediately displayed,
which means that it is possible to confirm the exposure state using
bulb exposure from the initial stage.
[0201] In the fourth embodiment, at the point in time where the
cycle time initially elapses, an image read from the image sensor
221 is displayed, but it is also possible to have an arrangement
where an image is displayed at the point in time where the cycle
time elapses a second and subsequent time, and only a notification
display is displayed up to then.
[0202] With the third and fourth embodiments of the present
invention, a specified period from start of the bulb exposure
displays that the bulb exposure is being executed on the rear
surface liquid crystal monitor 26, which is a display section. It
is therefore possible for the photographer to easily recognize that
the exposure operation is progressing, even in a period where the
brightness level of the exposed image immediately after exposure
has started is low.
[0203] In the third and fourth embodiments, as notification
information there are display indicating bulb exposure and display
of the elapsed time from the start of bulb exposure, but it is also
possible to omit the elapsed time. Also, the characters "bulb
exposure" and "BULB" are displayed in order to indicate that bulb
exposure has commenced, but this is not limiting and it is also
possible to have another display such as a symbol or an icon.
[0204] Also, with the third and fourth embodiments in the case
where the exposure operation is completed, if imaging is stopped in
step #153 (FIG. 19, FIG. 21) the original routine is returned to.
However, because the imaging section 291 accumulates signal charge
on the image sensor 221, it is also possible, similarly to step
#155 in FIG. 7 of the first embodiment, to read these signals,
generate an added image, and display the added image.
[0205] Further, with the third and fourth embodiments, when bulb
mode has been set added images are generated, but it is also
possible to generate and display added images in the case where
long time exposure is carried out, for example, exposure of a few
seconds. This approach can also be similarly adopted in other
embodiments.
[0206] Still further, with the third and fourth embodiments, in
step #31 the cycle time is manually set, but this is not limiting
and it is also completely possible, similarly to the second
embodiment for example, to automatically set the cycle time
according to subject brightness, so as to either shorten the cycle
time if the brightness is high, or conversely to extend the cycle
time if the brightness is low.
[0207] Next, a fifth embodiment of the present invention will be
described using FIG. 23 to FIG. 27. In the first to fourth
embodiments, because added images etc. are displayed at the time of
a long time exposure such as bulb exposure, the rear surface liquid
crystal monitor 26 was in a display state during long time exposure
However, bulb exposure lasts over a comparatively long time, which
means that the photographer must watch the display screen the
entire time. Also, a display device for image display used with an
imaging device such as a camera has comparatively high power
consumption, and so if the display state is maintained during
execution of bulb exposure the power supply batteries will be used
up in a short time.
[0208] With this embodiment therefore, in connection with update of
an added image, the display screen is only illuminated for a
predetermined time, and for a long time exposure such as bulb
exposure the photographer can observe without becoming
fatigued.
[0209] The structure of the fifth embodiment is partially similar
to the structure of the first and third embodiments, and so
detailed description of parts of the structure that are the same
will be omitted.
[0210] FIG. 23 is an external perspective drawing looking at a
digital single lens reflex camera of the fifth embodiment from a
rear surface side. It is different from the digital single lens
reflex camera of the first embodiment shown in FIG. 1 only in that
an LED (Light Emitting Diode) 41 for bulb display is arranged.
[0211] Specifically, a bulb display LED (Light Emitting Diode) 41
is arranged close to the viewfinder eyepiece on the rear surface of
the camera body 200. This bulb display LED 41 is lit up during
execution of bulb exposure, and shows that bulb exposure is in
progress to the user. The remaining members are the same as for the
digital single lens reflex camera shown in FIG. 1, and the same
members have the same reference numerals, with detailed description
being omitted.
[0212] FIG. 24 is a block diagram showing electrical circuits of
the digital single lens reflex camera of the fifth embodiment.
Compared to the electrical circuits of the first embodiment (refer
to FIG. 2), the fifth embodiment differs only in that the
temperature measurement circuit 231 has been omitted, and the
display LED 41 and a liquid crystal monitor backlight 26a are
added.
[0213] The omission of the temperature measurement circuit 231 is
the same as in the third embodiment shown in FIG. 16. Also, the
display LED 41 connected to the data bus 252 is lit up in response
to a light up command from the body CPU 251, and turned off in
response to a turn off command.
[0214] The liquid crystal monitor backlight 26a for illuminating
the rear surface liquid crustal monitor 26 is arranged at the rear
surface side of the rear surface liquid crystal monitor 26, and is
drive controlled by the liquid crystal monitor drive circuit 263.
The structure other than for the points of difference described
above is the same as for the first embodiment shown in FIG. 2, and
so detailed description will be omitted.
[0215] FIG. 25 shows a structure relating to image display during
exposure, for bulb exposure. Compared to the first embodiment
(refer to FIG. 3) there is a difference in that a display
illumination section 296a and a notification section 299 are
provided.
[0216] Specifically, the display illumination section 296a is
comprised of the liquid crystal monitor backlight 26a and the
liquid crystal monitor drive circuit 263, and performs illumination
of the image display section 296, so it is possible for the
photographer to easily observe the image display section 296 even
in a dark place. The notification section 299 is comprised of the
display LED 41 etc., which is lit up during bulb exposure to notify
the photographer. The notification section 299 is not limited to an
LED, and can be another display element such as a lamp.
[0217] With this type of arrangement, the control section 297
performs control so that image data that has been acquired by the
imaging section 291 is sequentially added by the adding processing
section 294 every set cycle time, and this added image is displayed
on the image display section 296. Display on the rear surface
liquid crystal monitor 26 at the time of bulb exposure is first
displaying notification information 330a on the rear surface liquid
crystal monitor 26 at the time of commencement of bulb exposure
(FIG. 27(a)), and the notification section 299 lighting up.
[0218] Also, image data from the start of exposure is cumulatively
added, and an added image is displayed on the rear surface liquid
crystal monitor 26 every time the cycle time elapses, as shown in
FIG. 27(b) to FIG. 27(g). At the stage of FIG. 27(b) the exposure
time is insufficient and so the image is dark, but after that if
the images are repeatedly cumulatively added a number of times it
gradually changes to a brighter image, it will become an image that
appears slightly over exposed, as shown in FIG. 27(g).
[0219] Further, at the time the cycle time elapses, the image
display section 296 is illuminated by the display illumination
section 296a from the time of update for a predetermined time, and
it possible to easily view the added image displayed on the rear
surface liquid crystal monitor 26. If a predetermined time elapses,
illumination by the display illumination section 296a is turned
off, and after that if the cycle time elapses again illumination by
the display section illumination section 296a is recommenced. In
this way, it is possible for the display illumination device 296a
to not always be on, and to reduce power consumption. Also, during
bulb exposure, since the notification section 299 is always in a
display state, it is possible for the photographer to easily
confirm that the bulb exposure is being executed.
[0220] Next, detailed operation of the digital single lens reflex
camera of the fifth embodiment of the present invention will be
described using the flowchart shown in FIG. 26. In the fifth
embodiment also, if a battery is fitted, the processing flow for
power on reset is executed. The processing flow for this power on
reset is the same as in FIG. 4 for the first embodiment, and so
detailed description will be omitted.
[0221] Also, cycle time input of step #31 in the processing flow of
the power on reset (refer to FIG. 4) is the same as the processing
flow of the cycle time input in the third embodiment (refer to FIG.
18) and so detailed description is omitted. Also, the shooting
operation of step #37 in the processing flow of the power on reset
(refer to FIG. 4) is the same as the processing flow of the
shooting operation in the first embodiment (refer to FIG. 6) and so
detailed description is omitted.
[0222] Next, the exposure operation of step #75 within the shooting
operation processing flow (FIG. 6) will be described using FIG. 26.
In the description, steps carrying out the same processing as the
flow of FIG. 7 for the first embodiment have the same step numbers
attached, and detailed description thereof is omitted.
[0223] If this processing flow is entered, first, similarly to step
#9 (refer to FIG. 4), it is determined whether or not bulb mode has
been set (#101). If the result of determination is that bulb mode
has not been set, normal exposure mode, such as program exposure
mode, is executed. Processing in normal exposure mode of step #103
to step #115 is similar to that of the first embodiment shown in
FIG. 7, and so detailed description will be omitted.
[0224] If the image display of step #115 is carried out there is
display of an exposed image and the liquid crystal monitor
backlight 26a is lit up, to illuminate the rear surface liquid
crystal monitor 26 (#116). If lighting up of the liquid crystal
monitor backlight 26a is carried out, the original routine is
returned to.
[0225] If the result of determination in step #101 is that bulb
mode has been set, then the added image storage region that has
been allocated inside the temporary storage section 293 is cleared
(#118B), and the cycle time that was manually input in step #31 is
set (#119B). Next, a timer for display cycle time timing is started
(#120B), and similarly to step #105, together with opening of the
shutter 213 imaging is commenced (#121B).
[0226] Next, the bulb display LED 41 is lit up, to display the fact
that the bulb exposure has commenced (#122B). This bulb display LED
41 is always kept on during bulb exposure, until it is turned off
in step #173B, which will be described later.
[0227] Display of notification information 330a for bulb exposure,
such as is shown in FIG. 27(a) is then started (#123B). That is, at
the time bulb exposure commences, the screen is jet black, and if
there is no display at all the photographer will be unsure as to
whether or not the exposure using bulb exposure has started. In
this embodiment therefore, by displaying the notification
information 330a it is possible for the photographer to recognize
that the exposure has started. Next, the liquid crystal monitor
backlight 26a is lit up (#124B) to illuminate the rear surface
liquid crystal monitor 26, making it possible for the photographer
to easily view the added image.
[0228] If the backlight is lit up, it is next determined whether or
not the timer for cycle time timing has reached the cycle time set
in step #119 (#125). If the result of determination is that the
cycle time has not elapsed, it is determined whether or not the
full pressing of the release button 21 has been released, that is,
whether or not the 2R switch is off (#151).
[0229] If the result of determination in step #151 is that the 2R
switch is off, it is determined whether or not 10 seconds has
elapsed from commencement of lighting up the liquid crystal monitor
backlight 26a (#155B). In this embodiment, a time is provided that
starts a timing operation in synchronization with lighting up of
the liquid crystal monitor backlight 26a, and in this step
determination is made based on the time measured by this timer.
[0230] If the result of determination in step #155B is that 10
second has not elapsed, then step #125 is returned to and a standby
state is entered where the determinations of step #125, step #151
and step #155 are repeatedly carried out. On the other hand, if the
result of determination in step #155B is that 10 second have
elapsed, then it is determined whether or not the cycle time that
was set in step #119B is 30 seconds or more (#157B). If the result
of determination is less than 30 seconds, processing returns to
step #125 and the operations described above are executed.
[0231] On the other hand, if the result of determination in step
#157B is that the set cycle time is 30 seconds or more,
illumination by the liquid crystal monitor backlight 26a is turned
off (#159B). In this embodiment, if the set cycle time is 30
seconds or more, then every time the added image is updated the
liquid crystal monitor backlight 26a is lit up for 10 seconds, and
the rear surface liquid crystal monitor 26 is illuminated. Once 10
seconds elapses, the liquid crystal monitor backlight 26a is turned
off. Also, if the set cycle time is less than 30 seconds, the
liquid crystal monitor backlight 26a is kept turned on.
[0232] In step #157B, determining whether or not to turn off the
backlight according to the set cycle time is because if the length
of time the backlight is on is made 10 seconds, in the event that
the set cycle time exceeds 10 seconds but is less than 30 seconds
the backlight will be repeatedly turned on and off in a short
period of time, causing illumination flicker, and making it
difficult to view the screen of the rear surface liquid crystal
display monitor 26. The set time instep #157B (30 seconds) and the
set time in step #155 (10 seconds) are only illustrative examples,
and they can be appropriately changed taking into consideration
reducing power supply consumption and ease of viewing the
display.
[0233] If the result of determination in step #125 is that the
cycle time has elapsed, then similarly to step #109 and step #111,
image forming of the image sensor 221 is stopped with the shutter
213 still open, and reading of pixel signals is carried out (#127,
#129). Next, the timer for cycle time timing is restarted (#130B),
and imaging on the image sensor 221 is commenced (#131B).
[0234] Next added image data is read from a storage region that was
previously stored in the storage region of the temporary storage
section 293, and adding processing for this image data and image
data read in step #129 is carried out (#133B). Image data of the
added image obtained here is stored in a storage region of the
temporary storage region 293 that is used for added image storage
(#135B).
[0235] An added image that has been added in step #135B is then
displayed on the rear surface liquid crystal monitor 26 (#137B),
the liquid crystal monitor backlight 26a is lit up, and the rear
surface liquid crystal monitor 26 is illuminated (#139B). If
lighting up of the backlight is carried out, step #125 is returned
to, and the previously described operations are executed By
executing from step #125 to step #139B a plurality of times, the
brightness level of the added image improves, as shown in FIG.
27(b) to FIG. 27(g).
[0236] The photographer will release the full pressing of the
release button 21 when the added image displayed on the rear
surface liquid crystal monitor 26 reaches an appropriate level or
the level desired by the photographer. Specifically, if the result
of determination in step #151 is that it has been determined that
the 2R switch has been turned off, then similarly to step #127
imaging is stopped together with closing of the shutter 213, and
the exposure operation is completed (#161B).
[0237] If imaging is stopped, next, similarly to step #129, reading
of image data from the image sensor 221 is carried out ((#163B),
and similarly to step #133 the image read out this time is added to
the previous added image (#165B). After this, similarly to step
#135, the added image is temporarily held (#167B) and the added
image is displayed on the rear surface liquid crystal monitor 26
(#169B).
[0238] In this embodiment, at the point in time where a finger is
taken away from the release button 21 and the bulb exposure is
completed, image signals accumulated in the image sensor 221 are
read out, these image signals are added to the previous added
image, and that added image is displayed. If display of the added
image is carried out, the liquid crystal monitor backlight 26a is
turned on, and the rear surface liquid crystal monitor 26 is
illuminated (#171B), and the bulb display LED 41 is turned off upon
completion of the bulb exposure (#173B).
[0239] In this way, with this embodiment imaging by the image
sensor 221 is stopped and image data output every time the cycle
time that was set in step #119B elapses (Y at #125). Addition
processing for this image data and the previous added image being
stored in the storage region of the temporary storage section 293
is carried out, and the result is stored. The added image stored in
each storage region is updated and displayed in the rear surface
liquid crystal monitor 26 every time the cycle time elapses, as
shown in FIG. 27, and it is possible to observe the exposure state
for bulb exposure in real time.
[0240] Also, with the fifth embodiment of the present invention, if
the cycle time elapses and the image is updated, the liquid crystal
monitor backlight 26a is turned on for a predetermined time (10
seconds in this embodiment). The liquid crystal monitor backlight
26a for the rear surface liquid crystal monitor 26 is not always
kept on during bulb exposure, which means it is possible to reduce
power consumption. Further, lighting of the liquid crystal monitor
backlight 26a is at the image cycle time, which means that the
photographer can observe the image with interest.
[0241] Further, with the fifth embodiment of the present invention,
in the event that the set cycle time is less than a predetermined
time (30 seconds in this embodiment), lighting of the liquid
crystal monitor backlight 26a is carried out continuously.
Therefore, turning on and off of the backlight is not repeated at
short intervals and there is no visually annoying flicker.
[0242] Also with the fifth embodiment of the present invention, the
LED for bulb display is lit once the bulb exposure is commenced,
and once bulb exposure is completed the bulb display LED 41 is
turned off. It is therefore possible to easily confirm whether or
not the bulb exposure is in progress, which is extremely
useful.
[0243] Next, a sixth embodiment of the present invention will be
described using FIG. 28. With the fifth embodiment of the present
invention, if the added image is updated, the liquid crystal
monitor backlight 26a is turned on for a predetermined time (10
seconds), and if the predetermined time elapses the liquid crystal
monitor backlight 26a is turned off. In the sixth embodiment, a
backlight button is provided, and the liquid crystal monitor
backlight 26a is turned on if this backlight button is
operated.
[0244] The structure of the sixth embodiment is the same as that of
the fifth embodiment shown in FIG. 23 to FIG. 25, the flowcharts
shown in FIG. 4, FIG. 6, and FIG. 18 are also the same, and bulb
mode exposure time display shown in FIG. 27, the exposure
information display shown in FIG. 10 and the update display shown
in FIG. 11 are also the same. The point of difference is that the
flowchart showing the exposure operation shown in FIG. 26 is
replaced with the flowchart in FIG. 28, and description will center
on this difference. Each of the steps within the flowchart shown in
FIG. 28 that are the same as the steps in the flowchart shown in
FIG. 26 have the same reference numerals attached, and detailed
description thereof is omitted.
[0245] If the processing flow for the exposure operation is
entered, it is determined whether or not it is bulb mode (#101),
and in the event that bulb mode has not been set, then similarly to
the fifth embodiment shown in FIG. 26, a normal exposure mode, such
as program exposure mode, is carried out. On the other hand, if
bulb mode has been set, then similarly to the fifth embodiment from
step #118B to step #124B are executed. At this time, lighting up of
the bulb display LED 41 and the liquid crystal monitor backlight
26a is also the same as with the fifth embodiment.
[0246] If the backlight is lit up, it is next determined whether or
not the cycle time has elapsed (#125). If the result of
determination is that the cycle time has not elapsed, then
similarly to the fifth embodiment it is determined in step #151
whether or not the 2R switch is off. If the result of determination
is that the 2R switch is off, then similarly to the fifth
embodiment steps #161 and after are executed.
[0247] On the other hand, if the result of determination in #151 is
that the 2R switch is not off, it is determined whether or not the
backlight button is on (#152B). The backlight button can be a
dedicated button provided on the rear surface of the camera body
200, but in this embodiment the OK button 31 is also used for this
function. Specifically, determination as to whether or not the OK
button 31 has been operated is carried out. If the result of
determination is that the backlight button is on, the liquid
crystal monitor backlight 26a is lit.
[0248] When the liquid crystal monitor backlight 26a is lit in step
#153B, the added image is not updated. After lighting the
backlight, if the image cycle time elapses within 10 seconds, the
added image is then also updated. In the event that the backlight
is lit, or the backlight button was not on in step #152B, steps
#155B and after are executed, as in the fifth embodiment.
[0249] In this way, with the sixth embodiment, the backlight button
is provided, and the liquid crystal monitor backlight 26a is turned
on if this backlight button is operated. It is therefore possible
to illuminate the rear surface liquid crystal monitor 26 and easily
confirm the added image by operating the backlight button, even
after initially lighting the liquid crystal monitor backlight 26a
and then turning it off when a predetermined time has elapsed.
[0250] Next, a seventh embodiment of the present invention will be
described using FIG. 29. In the fifth embodiment and the sixth
embodiment, the added images are only updated at set cycle time
intervals, and between the cycle times it is not possible to
confirm the state of progress of the bulb exposure. With the
seventh embodiment, an update button is provided, and if this
update button is operated update of the image is carried out
together with lighting of the backlight.
[0251] The structure of the seventh embodiment is the same as that
of the fifth embodiment shown in FIG. 23 to FIG. 25, the flowcharts
shown in FIG. 4, FIG. 6, and FIG. 18 are also the same, and bulb
mode exposure time display shown in FIG. 27, the exposure
information display shown in FIG. 10 and the update display shown
in FIG. 11 are also the same. The point of difference is that the
flowchart showing the exposure operation shown in FIG. 26 is
replaced with the flowchart in FIG. 29, and description will center
on this difference. Each of the steps within the flowchart shown in
FIG. 29 that are the same as the steps in the flowchart shown in
FIG. 26 have the same reference numerals attached, and detailed
description thereof is omitted.
[0252] If the flowchart for the exposure operation is entered, then
similarly to the fifth embodiment it is determined in step #125
whether or not the cycle time has elapsed. If the result of
determination is that the cycle time has elapsed, then similarly to
the fifth embodiment step #127 and after are executed.
[0253] On the other hand, if the result of determination in #125 is
that the cycle time has not elapsed, it is determined whether or
not the 2R switch is off (#151). If the result of determination is
that the 2R switch is off, then similarly to the fifth embodiment
steps #161B and after are executed. On the other hand, if the
result of determination is that the 2R switch is not in off, it is
then determined whether or not the update button is on (#154B).
[0254] The update button can be a dedicated button provided on the
rear surface of the camera body 200, but in this embodiment the OK
button 31 is also used for this function. Specifically,
determination as to whether or not the OK button 31 has been
operated is carried out. If the result of determination is that the
update button is not on, then similarly to the first embodiment
steps #155B and after are executed.
[0255] On the other hand, if the result of determination in step
#154B is that the update button is on, there is a jump to step
#127, and besides reading out image data similarly to the cycle
time elapsed time and generating added image data, in step #137 an
updated added image is displayed, and the liquid crystal monitor
backlight 26a is lit up (#139).
[0256] In this way, with the seventh embodiment of the present
invention, an update button is provided, and if this update button
is operated, by pseudo creating a state that is the same as when
the cycle time has elapsed, update of the added image is carried
out, and the liquid crystal monitor backlight 26a is lit.
Therefore, when the bulb exposure progresses, it is possible to
confirm the state of progress of the bulb exposure at an arbitrary
timing other than the update timing of the image.
[0257] Next, an eight embodiment of the present invention will be
described using FIG. 30 and FIG. 31. With the first to seventh
embodiments, the cycle time for the added image could not be
changed during bulb exposure. With the eighth embodiment, it is
made possible to change this cycle time during an exposure
operation for bulb exposure.
[0258] The structure of the eighth embodiment is the same as that
of the fifth embodiment shown in FIG. 23 to FIG. 25, the flowcharts
shown in FIG. 4, FIG. 6, and FIG. 18 are also the same, and bulb
mode exposure time display shown in FIG. 27, the exposure
information display shown in FIG. 10 and the update display shown
in FIG. 11 are also the same. The point of difference is that the
flowchart showing the exposure operation shown in FIG. 26 is
replaced with the flowcharts in FIG. 30 and FIG. 31, and
description will center on this difference. Each of the steps
within the flowcharts shown in FIG. 30 and FIG. 31 that are the
same as the steps in the flowchart shown in FIG. 26 have the same
reference numerals attached, and detailed description thereof is
omitted.
[0259] If the flowchart for the exposure operation is entered, then
similarly to the fifth embodiment it is determined in step #125
whether or not the cycle time has elapsed. If the result of
determination is that the cycle time has elapsed, then similarly to
the fifth embodiment step #127 and after are executed.
[0260] On the other hand, if the result of determination in #125 is
that the cycle time has not elapsed, it is determined whether or
not the 2R switch is off (#151). If the result of determination is
that the 2R switch is off, then similarly to the fifth embodiment
steps #161B and after are executed. On the other hand, if the
result of determination is that the 2R switch is not off, it is
then determined whether or not the information setting dial 24 has
been operated (#181B).
[0261] If the result of determination in step #181B is that the
information setting dial 24 has not been operated, then similarly
to the fifth embodiment steps #155B and after are executed. On the
other hand, if the information setting dial 24 has been operated,
the subroutine for cycle time input described using FIG. 18 is
executed (#183B). In this subroutine for cycle time update, the
operation state of the information setting dial 24 is determined,
and it is possible to change the cycle time.
[0262] If cycle time input is completed, then exposure information
display is carried out (#185B) similarly to step #13 (FIG. 4). The
cycle time that was changed in step #183B is displayed. Next,
similarly to step #111B, a manually input cycle time is set
(#187B). If setting of cycle time is completed, there is a jump to
step #127, and following that determination as to whether or not
the cycle time has elapsed in step #125 is carried out based on the
cycle time that has been changed in this step.
[0263] In this way, with the eighth embodiment of the present
invention, if the information setting dial 24 is operated during
execution of bulb exposure, the cycle time is changed in accordance
with the operation state of the information setting dial 24, and
after that the cycle time for added images is changed based on the
changed cycle time. Therefore, when the bulb exposure progresses,
if the cycle time is shortened or lengthened it is possible to
change the cycle time for images.
[0264] Also, as has been described, in the fifth to eighth
embodiments of the present invention, the display screen of the
rear surface liquid crystal monitor 26 is illuminated for only a
predetermined time in association with update of the image display
on the rear surface liquid crystal monitor 26. It is therefore
possible to limit consumption of the power supply battery as much
as possible.
[0265] In the fifth to eighth embodiments, the rear surface liquid
crystal monitor 26, as the display section, is illuminated by the
liquid crystal monitor backlight 26a, but as long as the display
illumination section performs illumination so that it is possible
to easily confirm display on the display section, it is not limited
to a backlight. The illumination section can be appropriately
selected according to the members used as the display section.
[0266] Also, in the fifth to eighth embodiments, in order to
indicate the fact that bulb exposure has started, notification
display for bulb exposure was displayed at the time of commencing
bulb exposure, it is also possible to continue display during
execution of bulb exposure, and at this time it is possible to
display elapsed time after commencement of bulb exposure. Also, the
characters "bulb exposure" and "BULB" are displayed as the bulb
exposure notification display, but this is not limiting and it is
also possible to have another display such as a symbol or an
icon.
[0267] Next, a ninth embodiment of the present invention will be
described using FIG. 32 to FIG. 35. In the first to eighth
embodiments, update of added images was carried out at cycle time
intervals. However, bulb exposure etc. extends over a comparatively
long time, and there is no variation in a display image until the
image is updated, which means that there is problem of looking at
the display image for that entire time.
[0268] Therefore, in the ninth embodiment, notification is given to
the photographer at the time of image update using a sound
generating section or the like. In this way, it is possible for the
photographer to observe a display image without difficulty in a
long time exposure such as bulb exposure.
[0269] The structure of the ninth embodiment is partially similar
to the structure of the first and third embodiments, and so
detailed description of parts of the structure that are the same
will be omitted.
[0270] The external appearance of a digital single lens reflex
camera of the ninth embodiment of the present invention is the same
as in FIG. 1. Electrical circuits of this digital single lens
reflex camera are shown in FIG. 32. Compared to the electrical
circuits of the first embodiment (refer to FIG. 2), the ninth
embodiment differs only in that the temperature measurement circuit
231 has been omitted, a buzzer 287 has been added, and a liquid
crystal monitor backlight 26a has been added.
[0271] The omission of the temperature measurement circuit 231 is
the same as in the third embodiment shown in FIG. 16. Also, the
liquid crystal monitor backlight 26a is arranged on the rear
surface of the liquid crystal monitor 26, and illumination of the
rear surface liquid crystal monitor 26 is the same as for the fifth
embodiment in FIG. 24.
[0272] Also, the buzzer 287 connected to the data bus 252 is a
sound generating section described later, and performs notification
display using sound when an image is updated at the time of bulb
exposure. The structure other than for the points of difference
described above is the same as for the first embodiment shown in
FIG. 2, and so detailed description will be omitted.
[0273] FIG. 33 shows a structure relating to image display during
exposure, for bulb exposure. Compared to the first embodiment
(refer to FIG. 3) there is a difference in that the setting section
298 is omitted, and the sound generating section 299a is provided.
Naturally, the setting section 298 can also be provided in the
ninth embodiment, but as it is not important it has been omitted in
FIG. 33.
[0274] Also, in the ninth embodiment the sound generating section
299a connected to the control section 297 is provided, and this
sound generating section 299a is constituted by a buzzer 287. The
sound generating section 299a issues a notification to the
photographer using a notification sound every time the added image
displayed on the image display section 296 is updated.
[0275] With this type of arrangement, display on the rear surface
liquid crystal monitor 26 at the time of bulb exposure is first
displaying notification information 321a at the time of
commencement of bulb exposure to notify that the bulb exposure has
commenced (FIG. 35(a)).
[0276] If the initial cycle time has elapsed, image data is read
from the imaging section 291, and an added image (at the initial
stage, with the initially read image data directly) is displayed on
the rear surface liquid crystal monitor 26 as shown in FIG. 35(b)
together with the notification information 321b (with this example,
cycle time is 30 seconds). Also, at the same time a sound (for
example a beep) is output from the sound generating section 299a to
notify of update of the image.
[0277] After that, image data that has been acquired by the imaging
section 291 is sequentially added by the adding processing section
294 every set cycle time, and this added image is displayed on the
image display section 296. As shown in FIG. 35(c) to FIG. 35(g),
every time the added image is updated, notification information
320c to 320g is displayed superimposed, and at the same time
notification is also carried out using a notification sound from
the sound generating section 299a.
[0278] Also, at the stage of FIG. 35(b) the exposure time is
insufficient and so the image is dark, but after that if the images
are gradually changed to brighter images and the cumulative adding
is repeated a number of times, it will become an image that appears
over exposed, as shown in FIG. 35(g). In addition to this
notification information 321b to 320g being present during
execution of bulb exposure, the elapsed time for the bulb exposure
is displayed.
[0279] Next, detailed operation of the digital single lens reflex
camera of the ninth embodiment of the present invention will be
described using the flowchart shown in FIG. 34. In the ninth
embodiment also, if a battery is fitted, the processing flow for
power on reset is executed. The processing flow for this power on
reset is the same as in FIG. 4 for the first embodiment, and so
detailed description will be omitted.
[0280] Also, cycle time input of step #31 in the processing flow of
the power on reset (refer to FIG. 4) is the same as the processing
flow of the cycle time input in the third embodiment (refer to FIG.
18) and so detailed description is omitted. Also, the shooting
operation of step #37 in the processing flow of the power on reset
(refer to FIG. 4) is the same as the processing flow of the
shooting operation in the first embodiment (refer to FIG. 6) and so
detailed description is omitted.
[0281] Next, the exposure operation of step #75 within the shooting
operation processing flow (FIG. 6) will be described using FIG. 34.
In the description, steps carrying out the same processing as the
flow of FIG. 7 for the first embodiment have the same step numbers
attached, and detailed description thereof is omitted.
[0282] If this processing flow is entered, first, similarly to step
#9 (refer to FIG. 4), it is determined whether or not bulb mode has
been set (#101). If the result of determination is that bulb mode
has not been set, normal exposure mode, such as program exposure
mode, is executed in step #103 to step #115. This normal exposure
mode processing is the same as for the flow of FIG. 7, and so
detailed description is omitted.
[0283] If the result of determination in step #101 is that bulb
mode has been set, then first the added image storage region that
has been allocated inside the temporary storage section 293 is
cleared (#119C), and the cycle time that was manually input in step
#31 is set (#120C). Next, a timer for display cycle time timing is
started (#121C), and similarly to step #105, together with opening
of the shutter 213 imaging is commenced (#122C).
[0284] Display of notification information 321a for bulb exposure,
such as is shown in FIG. 35(a) is then started (#123C). That is, at
the time bulb exposure commences, the screen is jet black, and if
there is no display at all the photographer will be unsure as to
whether or not the exposure using bulb exposure has started. In
this embodiment also therefore, similarly to the third embodiment,
by displaying the notification information 321a it is possible for
the photographer to recognize that the exposure has started.
[0285] If the display of notification information is started, then
next the liquid crystal monitor backlight 26a is lit up (#124C), to
illuminate the rear surface liquid crystal monitor 26. In this way,
the display screen of the liquid crystal monitor 26 becomes bright
and it is possible to view.
[0286] Next, it is determined whether or not the timer for cycle
time timing has reached the cycle time set in step #120C (#125). If
the result of determination is that the cycle time has not elapsed,
it is determined whether or not the full pressing of the release
button 21 has been released, that is, whether or not the 2R switch
is off (#151).
[0287] If the result of determination in #151 is that the 2R switch
is not off, it is next determined whether or not the image display
is maintained over a predetermined time (#161C). In this step, it
is determined whether or not the timer for cycle time timing that
started a timing operation in step #121C (or in step #131C the
second and subsequent times) has reached a predetermined time, for
example, 10 seconds.
[0288] If the result of determination in step #161C is that the
predetermined time has not been reached, step #125 is returned to
and image display by the liquid crystal monitor 26 and lighting of
the liquid crystal monitor backlight 26a are continued.
[0289] On the other hand, if the result of determination in step
#161C is that the predetermined time has elapsed the liquid crystal
monitor backlight 26a is turned off (#163C) and display of the
added image on the liquid crystal monitor 26 is turned off (#165C).
This is in order to reduce power supply consumption, so that the
added image is displayed for only a predetermined time at the time
of update.
[0290] With this embodiment, notification display for the bulb
exposure is displayed on the liquid crystal monitor 26, but by also
turning notification display for bulb exposure in addition to
turning off the image display of step #165C, and turning off the
power supply to the liquid crystal monitor 26 itself, it is
possible to further reduce power supply consumption. In step #165C,
if the image display is turned off, step #125 is returned to.
[0291] If the result of determination in step #125 is that the
cycle time has elapsed, then similarly to step #109 and step #111,
image forming of the image sensor 221 is stopped with the shutter
213 still open, and reading of pixel signals is carried out (#127,
#129).
[0292] Next 1 is added to the counter (#130C). The update counter
is reset at the same time as the timer is started in step #121, and
every time this step #130 is passed through 1 is added. By
multiplying a count value of this update counter by the cycle time
set in step #120, it is possible to obtain a cumulative time from
when the exposure using bulb exposure started.
[0293] Next, the timer for cycle time timing is restarted (#131C),
and imaging on the image sensor 221 is commenced (#133C).
[0294] Next added image data is read from a storage region that was
previously stored in the storage region of the temporary storage
section 293, and adding processing for this image data and image
data read in step #129 is carried out (#135C). Image data of the
added image obtained here is stored in a storage region of the
temporary storage section 293 that is used for added image storage
(#137C).
[0295] If accumulation of the added image is completed, the added
image stored in the temporary storage section 293 is next displayed
on the rear surface liquid crystal monitor 26 (#139). Illumination
of the liquid crystal monitor 26 is then carried out using the
liquid crystal monitor backlight 26a. As has been described, with
image display using the liquid crystal monitor 26 and illumination
using the liquid crystal monitor backlight 26a, display of an added
image is turned off if added image display continues for a
predetermined time (#163C, #165C).
[0296] Next, it is determined whether or not the cycle time set in
step #120C is 30 seconds or more (#143C). If the result of
determination is that the set cycle time is 30 seconds or more, a
notification sound is emitted for a predetermined time (for example
0.3 seconds) by the sound generating section 299a (buzzer 287). It
is possible to let the photographer know that the image has been
updated using the notification sound.
[0297] Here, the fact that whether or not to emit a notification
sound is switched depending on whether or not the set cycle time is
a determined time or longer is because in the event that the cycle
time is short, intervals between emission of the notification sound
will be short, giving a noisy impression. This determined time is
not limited to 30 seconds, and can be appropriately altered. If the
result of determination in step #143C is that the set cycle time is
less than 30 seconds, or if the notification sound has been emitted
in step #145C, step #125 is returned to and the previously
described operations are executed.
[0298] In step #122C, at the initial stage where the imaging
operation has commenced notification information 321a is displayed
on the liquid crystal monitor 26, as shown in FIG. 35(a), and
illuminated by the liquid crystal monitor backlight 26a. If it is
determined in step 161C that the predetermined time has elapsed,
illumination by the liquid crystal monitor backlight 26a is turned
off.
[0299] Next, if it is determined in step #125 that the cycle time
has elapsed a formed image is read out, and the image at this time
is displayed as shown in FIG. 35(b) (#139C), and at the same time
if the set time is 30 seconds or greater a notification sound is
emitted by the sound generating section 299a (#145C). Also,
illumination by the liquid crystal monitor backlight 26a is carried
out for a predetermined time (from #141C to #163C).
[0300] As shown in FIG. 35(c) to FIG. 35(g), every time it is
determined in step #125 that the cycle time has elapsed, the added
image and notification display 320c to 320g are updated. At this
time a notification sound is also emitted for a predetermined time.
At the initial stage the added image is insufficiently bright, and
so the screen remains dark, but with the screen becoming brighter
as the accumulation time increases the photographer completes the
bulb exposure at the point in time when they determine that their
desired brightness has been attained.
[0301] As the notification information 321b to 320g, as shown in
FIG. 35 there is display indicating that bulb exposure is being
executed, and display of cumulative exposure time for the bulb
exposure. Also in this embodiment, the cumulative exposure time is
obtained using a count value of the update counter that is made to
count in step #130C and the set cycle time, but this is not
limiting and it is also possible to provide a counter for obtaining
the cumulative exposure time at the time of bulb exposure, and
displaying elapsed time based on this counter.
[0302] If it is determined in step #151 that the 2R switch has been
turned off as a result of the photographer taking their finger off
the release button 21 at the point in time where their desired
brightness has been reached, then similarly to step #127 imaging is
stopped together with closing of the shutter 213 (#153).
Specifically, the exposure operation is completed, and after that
the original routine is returned to.
[0303] In this way, with the ninth embodiment of the present
invention, every time the set cycle time elapses (Y at #125),
imaging by the image sensor 221 is stopped, image data is output,
this image data and an immediately preceding added image stored in
the storage region of the temporary storage section 293 are added,
and the result is stored. The added image stored in each storage
region is updated and displayed in the rear surface liquid crystal
monitor 26 every time the cycle time elapses, as shown in FIG.
35.
[0304] Also, with this embodiment, every time the image is updated
a notification sound is emitted by the sound generating section
299a, and when this notification sound is emitted, since the rear
surface liquid crystal monitor 26 should only be viewed when the
notification sound is emitted, the photographer can view without
any problem.
[0305] Further, with this embodiment, after the image has been
updated the liquid crystal monitor backlight 26a is only lit for a
predetermined time, which means that it is possible to reduce
consumption of the power supply. Also, since the notification sound
by the sound generating section 298 is stopped if the set cycle
time is short, it is possible to prevent the notification sound
being emitted at short time intervals.
[0306] In this embodiment, as notification information there are
display indicating bulb exposure and display of the elapsed time
from the start of bulb exposure, but it is also possible to omit
the elapsed time. Also, the characters "bulb exposure" and "BULB"
are displayed in order to indicate that bulb exposure has
commenced, but this is not limiting and it is also possible to have
another display such as a symbol or an icon.
[0307] Next, a tenth embodiment of the present invention will be
described using FIG. 36 to FIG. 40. In the first to ninth
embodiments, added images were displayed over the course of a long
time exposure, such as bulb exposure. However, when confirming the
image after exposure, there will be times when it is instantly
recognized that exposure is wrong.
[0308] In the tenth embodiment therefore, individual added images
acquired over the course of a long time exposure such as bulb
exposure are stored, so that it is possible to confirm the
individual added images after exposure.
[0309] The structure of the tenth embodiment is partially similar
to the structure of the first and third embodiments, and so
detailed description of parts of the structure that are the same
will be omitted.
[0310] The external appearance of the digital single lens reflex
camera of the tenth embodiment is similar to FIG. 1, and electrical
circuits are similar to FIG. 16, and so detailed description will
be omitted.
[0311] Next, the structure relating to image display during
exposure, in bulb exposure etc., will be described using FIG. 36.
Similarly to FIG. 3, the control section 297 is constructed of a
body CPU 251 for controlling the overall digital single lens reflex
camera.
[0312] The imaging section 291, similarly to FIG. 3, includes the
image sensor 221 image sensor drive circuit 223, ADC circuit 225
and dark current elimination circuit 227, and outputs image data
based on image signals. Output of the imaging section 291 is
connected to the adding processing section 294.
[0313] The adding processing section 294 is made up of the body CPU
251 and an image processing circuit 257. The adding processing
section 294 is input with image data from the imaging section 291,
and also input with previous added image data stored in the storage
region of the added image storage section 292, and adds the two
together to generate an added image and outputs the result to the
added image storage section 292.
[0314] The added image storage section is constituted by a
temporary storage device such as SDRAM 267, and has a plurality of
storage regions divided into from storage region A to storage
region n, with each storage region sequentially storing the added
image data thus far.
[0315] That is, initial image data is stored in the storage region
A, then if image data is output from the imaging section 291,
adding processing for that image data and previous added image data
stored in the storage region A are carried out, and new added image
data is stored in the storage region B. In this manner, in
accordance with control by the control section 297, every time
image data is output from the imaging section 291, image data to
that point is subjected to adding processing and sequentially
stored in the storage regions in the added image storage section
292.
[0316] The image display section 296, similarly to FIG. 3, is
comprised of a liquid crystal monitor 26 and a liquid crystal
monitor drive circuit 263, and displays image data that has been
read from the added image storage section 292.
[0317] A selection section 298a is made up of a cross-shaped button
20 and an OK button 31, and selects a finally stored image from
among a plurality of subject images formed at the time of bulb
exposure. The image storage section 295, similarly to FIG. 3, is
comprised of a storage medium 277, and stores an image selected by
the selection section 298a.
[0318] With this type of structure, the control section 297 causes
output of image data from the imaging section 291 at intervals of
the set cycle time, and the adding processing section 294 adds this
image data to the preceding added image stored in the added image
storage section 292. Added values for image data up to the time of
respective image data output are then stored in a respective
storage region of the added image storage section 292.
[0319] An image based on the image data stored in the added image
storage section 292 is then displayed on the image display section
296. Image data stored in storage region A has the earliest
exposure, and so is an mage that appears under exposed, as shown in
FIG. 39(a). Next, since the next stored image of storage region B
is added to the image data having the initial exposure, it becomes
slightly brighter as shown in FIG. 39(b).
[0320] Every time image data is sequentially accumulated in the
added image storage region 292, the image becomes gradually
brighter, with the image of the storage region D approaching
correct exposure, as shown in FIG. 39(d), and if accumulation of
image data continues further it becomes an over exposed mage as
shown in FIG. 39(g) that is stored in storage region G.
[0321] If exposure is completed, images based on image data stored
in the respective storage regions are displayed in tabulated form
as thumbnails, as shown in FIG. 40, on the image display section
296. In the case immediately after completion of bulb exposure, a
selection frame 341 indicates an image corresponding to the final
exposure.
[0322] The photographer selects an image that accords with their
intentions from among the images shown in table form by moving the
selection frame 341 by operating the cross-shaped button 30 until
it indicates a good image, and then using the OK button 31. If the
image is selected, that image is stored in the storage medium
277.
[0323] Next, detailed operation of the digital single lens reflex
camera of the tenth embodiment of the present invention will be
described using the flowchart shown in FIG. 37. In the tenth
embodiment also, if a battery is fitted, the processing flow for
power on reset is executed. The processing flow for this power on
reset is the same as in FIG. 4 for the first embodiment, and so
detailed description will be omitted.
[0324] Also, cycle time input of step #31 in the processing flow of
the power on reset (refer to FIG. 4) is the same as the processing
flow of the cycle time input in the third embodiment (refer to FIG.
18) and so detailed description is omitted.
[0325] The shooting operation of step #37 in the processing flow of
the power on reset (refer to FIG. 4) will be described using the
flowchart shown in FIG. 37. Processing flow of this shooting
operation is the same as the processing flow of the shooting
operation in the first embodiment shown in FIG. 6, and steps #61 to
#79, step #83 and step #85 Steps carrying out the same processing
therefore have the same step numbers attached, and description will
center on pints of difference.
[0326] If the 1R switch is turned on, processing flow for the
shooting operation is entered, processing advances to step #61 to
step #69, and if the 2R switch is turned on there is a transfer to
operation for carrying out exposure in step #71 and after.
[0327] The exposure operation is started in step #75. In this step,
travel of the front curtain of the shutter 213 commences, together
with charge accumulation of the image sensor 221. Then, if a time
corresponding to the shutter speed acquired in step #67 or a
shutter speed that was manually set by the photographer has
elapsed, travel of the rear curtain of the shutter 213 starts, and
charge accumulation of the image sensor 221 is terminated.
[0328] Here, if bulb mode has been set, then while the release
button 21 is being pressed down completely the shutter 213 is open,
and at this time image data is repeatedly acquired using the image
sensor 221 at intervals of the cycle time, and an added image is
displayed on the liquid crystal monitor 26 while being updated,
based on this image data. This exposure operation will be described
in detail later using FIG. 38.
[0329] If the exposure operation is completed, an instruction to
open up the aperture 103 is output to the CPU 111, the aperture 103
is opened up (#77), and an operation to restore the movable mirror
201 to the lowered position is carried out (#79). Then, as in step
#65, it is determined whether or not there is bulb mode (#81D).
[0330] If the determination in step #81D is that it is not bulb
mode, image processing of data for a normal image read from the
image sensor 221 and temporarily stored in the SDRAM 267, or for an
added image, is carried out, and the image processed image data is
stored in the storage medium 277 (#83). Display of the image that
is displayed on the rear surface liquid crystal monitor 26 is the
stopped (#85). Once image display is stopped, the original routine
is returned to.
[0331] If the result of determination in step #81D is that there is
bulb mode, all added images are displayed as a list (#89D). That
is, thumbnail display is carried out as shown in FIG. 39A based on
image data stored in respective regions of the added image storage
section 292. The newest image, that is the finally exposed image,
is then selected, and display of the selection frame 341 is carried
out (#91D).
[0332] Next, determination as to whether or not the cross-shaped
button 30 has been operated is carried out (#93D), and if it has
not been operated there is a jump to step #97D. On the other hand,
if the result of determination is that the cross-shaped key 30 has
been operated the selection frame 341 is moved in accordance with
the operation direction and the selected image is changed
(#95D).
[0333] It is then determined whether or not the OK button 31 is
operated (#97D), and if the result of determination is that the OK
button 31 has not been operated step #93 is returned to and the
previously described processing is executed. On the other hand, if
the result of determination is that the OK button 31 has been
operated then image data of the selected image is read out from the
added image storage section 292 (#99D). If reading is complete,
processing advances to previously described step #83, and
processing is executed.
[0334] Next, the exposure operation of step #75 within the shooting
operation processing flow of FIG. 37 will be described using FIG.
38. In the description, steps carrying out the same processing as
the flow of FIG. 7 for the first embodiment have the same step
numbers attached, and detailed description thereof is omitted.
[0335] If this processing flow is entered, first, similarly to step
#9, it is determined whether or not bulb mode has been set (#101).
If the result of determination is that bulb mode has not been set,
normal exposure mode, such as program exposure mode, is executed in
step #103 to step #115. This normal exposure mode processing is the
same as for the flow of FIG. 7, and so detailed description is
omitted.
[0336] If the result of determination in step #101 is that bulb
mode has been set, then first the entire added image storage region
that has been allocated inside the added image storage section 293
is cleared (#119D), and the cycle time that was manually input in
step #31 is set (#120D).
[0337] Next, a timer for display cycle time timing is started
(#121), and similarly to step #105, together with opening of the
shutter 213 imaging is commenced (#123). Next, it is determined
whether or not the timer for cycle time timing has reached the
cycle time set in step #120D (#125).
[0338] If the result of determination is that the cycle time has
not elapsed, it is determined whether or not the full pressing of
the release button 21 has been released, that is, whether or not
the 2R switch is off (#151). In the event that the 2R switch is on
and the cycle time has not elapsed, a standby state is entered
where the determinations at steps #125 and #151 are alternately
executed.
[0339] If the result of determination in step #125 is that the
cycle time has elapsed, then similarly to step #109 and step #111,
image forming of the image sensor 221 is stopped with the shutter
213 still open, and reading of pixel signals is carried out (#127,
#129). Next, the timer for cycle time timing is restarted (#131D),
and imaging on the image sensor 221 is commenced (#133D).
[0340] Next added image data is read from a storage region that was
previously stored in the storage region of the added image storage
section 293, and adding processing for this image data and image
data read in step #129 is carried out (#135D). Image data for the
added image acquired here is stored in a storage region adjacent to
the storage region previously read by the added image storage
section 293 (#137D). This stored added image is then displayed on
the rear surface liquid crystal monitor 26 (#139D), step #125 is
returned to, and the previously described steps are executed.
[0341] If the result of determination in step #151 is that the full
pressing of the release button 21 has been released, that is, it
has been determined that the 2R switch has been turned off, then
imaging is stopped together with closing of the shutter 213 (#153).
Specifically, the exposure operation is completed, and after that
the original routine is returned to.
[0342] In this way, every time the cycle time set in step #31
(#120D) elapses (Y at #125), imaging by the image sensor 221 is
stopped, image data is output, added images of this image data and
an immediately preceding added image stored in the storage region
of the added image storage section 292 are obtained, and
sequentially stored. The added image stored in each storage region
is updated and displayed in the rear surface liquid crystal monitor
26 every time the cycle time elapses, as shown in FIG. 39. At the
point in time when the cycle time initially elapses, since cycle
time is short a completely dark image results, and the image is
gradually made brighter by cumulatively adding image data each time
the cycle time elapses.
[0343] With the tenth embodiment, if bulb mode has been set an
exposure operation is repeated during the bulb exposure operation
at cycle time intervals, image data acquired at this time and a
previous added image are added, this added data is respectively
independently stored in the added image storage section 292, and
after completion of exposure it is possible to select from a
plurality of added images. It is therefore possible to acquire an
image of an appropriate exposure level after exposure.
[0344] Also, with this embodiment added images are displayed as a
list on the liquid crystal monitor 26. It is therefore possible to
compare the individual added images and easily select the image the
photographer desires. Further, with this embodiment a period for
acquiring repeated output from the imaging section 291 (cycle time)
is variable, and so it is possible to make it an optimum period
according to characteristics of the subject image.
[0345] Further, with this embodiment added images during exposure
are displayed in accordance with progress of the exposure, which is
useful, with bulb exposure, in determining the time at which to
complete exposure.
[0346] With this embodiment added images are displayed in order to
show exposure level during exposure, but if it is simply used to
finally select an image it is possible to omit the display of added
images during exposure.
[0347] Further, with this embodiment reading out of a selected
image is carried out in step #97 and step #99, but the selected
image is not limited to one and it is also possible to read out a
plurality of added images.
[0348] As has been described above, with each of the embodiments of
the present invention, image data that has been repeatedly read
from an imaging section 291 is sequentially added, and added image
data is generated and displayed on the image display section 296.
It is therefore possible to confirm the advancement of exposure at
the time of a long time exposure such as bulb exposure. It is also
possible to display added images that have been stored in an added
image storage section in the form of a list after a long time
exposure such as bulb mode. It is therefore possible to select an
image that conforms to the intended exposure by the photographer
after exposure.
[0349] With each of the embodiments of the present invention, if
the bulb mode has been set, the release button 21 is pressed down
fully, and until this full pressing down is released, that is,
while the 2R switch is on, the shutter is opened and the exposure
operation carried out. However, as well as this method of
operating, it is also possible, for example, to start the exposure
operation when the release button 21 is pressed down fully (first
release operation), continue the exposure operation even if the
full pressing of the release button 21 is released, and stop the
exposure operation when the release button 21 is pressed down fully
again (a second release operation carried out after the first
release operation).
[0350] Also, in the first, second and fifth to eighth embodiments,
if the exposure operation is completed, an image is read out in
steps #155 (FIG. 7, FIG. 14) and step #163B (FIG. 26, FIG. 28 to
FIG. 30), and an added image that has been added to this image is
displayed (#161, #169B). However, it is also possible to not read
an image in step #155 or step #163B, but display the final added
image acquired in step #137.
[0351] Further, in each of the third, fourth, ninth and tenth
embodiments of the present invention, when the exposure is
completed, if imaging is stopped in step #153 (FIG. 19, FIG. 21,
FIG. 34, FIG. 38) there is no reading of image signals from the
image sensor 221. However, similarly to the first, second and fifth
to eighth embodiments, it is totally possible to read an image
after stopping imaging, perform addition, and display the added
image.
[0352] Further, with the second embodiment of the present
invention, an example is shown where added images are generated
even if a long time exposure is carried out, but in other
embodiments also it is also possible to generate and display added
images in the case where long time exposure is carried out, for
example, exposure of a few seconds.
[0353] Further, in the first and third to eighth embodiments, the
cycle time is manually set in step #31. However, this is not
limiting and it is also completely possible, similarly to the
second embodiment, to automatically set the cycle time according to
subject brightness, so as to either shorten the cycle time if the
brightness is high, or conversely to extend the cycle time if the
brightness is low.
[0354] Also, this embodiment has been described as an example
applied to a single lens reflex type of digital camera, but besides
being applied to a single lens reflex camera there is no problem
with the present invention being applied to a compact type digital
camera or a camera of the type incorporated into a mobile telephone
or PDA (mobile information terminal: Personal Digital Assistant)
etc. As long as it is has an imaging device capable of long time
exposures, such as bulb mode, it is possible to apply the present
invention.
[0355] Description has been given above embodiments of the present
invention, but the present invention is not limited to these
embodiments, and structural elements may be modified in actual
implementation within the scope of the gist of the embodiments. It
is also possible form various inventions by suitably combining the
plurality structural elements disclosed in the above described
embodiments. For example, it is possible to omit some of the
structural elements shown in the embodiments. It is also possible
to suitably combine structural elements from different
embodiments.
* * * * *