|
Digital Camera Patent Abstract
A digital camera is provided with a special successive shooting
mode wherein an imaging device makes a series of successive shots
upon each shutter release operation, including at least a non-flash
shot and at least a flash shot. When a shutter button is pressed
halfway in the successive shooting mode, an exposure condition deciding
device decides an exposure condition common to the non-flash and
flash shots, or individual exposure conditions for the non-flash
shot and the flash shot. When the shutter button is fully pressed,
the imaging device starts the successive shots of one series. Images
captured by the non-flash shot and the flash shot are displayed
on an LCD panel. Before the imaging device starts the successive
shots, necessary warning marks are displayed together with the exposure
conditions decided by the exposure condition deciding device.
Digital Camera Patent Claims
1. A digital camera provided with a special successive shooting
mode wherein an imaging device makes a series of successive shots
upon each shutter release operation, including at least a non-flash
shot and at least a flash shot that is made synchronously with a
flash light from a flash device, said digital camera comprising:an
exposure condition deciding device for deciding exposure condition
of said imaging device through photometry and calculation, wherein
said exposure condition deciding device decides a common exposure
condition to the non-flash shot and the flash shot in said successive
shooting mode.
2. A digital camera as claimed in claim 1, further comprising a
light control device for controlling volume of the flash light from
said flash device, said light control device being successively
driven upon a predetermined operation or at predetermined timing
while said imaging device is being driven successively in said successive
shooting mode.
3. A digital camera as claimed in claim 1, further comprising a
device for changing imaging sensitivity of said imaging device,
wherein the imaging sensitivity is changed when under-exposure will
occur under the exposure condition decided based on the present
sensitivity in said successive shooting mode.
4. A digital camera as claimed in claim 1, further comprising a
judging device for judging whether to lower photometric sensitivity
and imaging sensitivity when a measured subject brightness value
is above a predetermined value, wherein when said judging device
judges to lower the photometric sensitivity and imaging sensitivity,
said exposure condition deciding device carries out the photometry
and calculation at the lowered photometric and imaging sensitivities
to decide the exposure conditions, and said imaging device makes
the successive shots at the lowered imaging sensitivity.
5. A digital camera as claimed in claim 1, further comprising a
display device for displaying images based on image data obtained
through said imaging device, wherein said display device displays
images as captured by the successive shots of one series in said
successive shooting mode.
6. A digital camera as claimed in claim 5, wherein said display
device displays the images as captured by the successive shots of
one series, simultaneously on a screen.
7. A digital camera as claimed in claim 5, wherein said display
device displays the images as captured by the successive shots of
one series, one by one on a screen.
8. A digital camera as claimed in claim 7, wherein said display
device displays the images as captured by the successive shots of
one series, sequentially while switching over the screen at predetermined
time intervals.
9. A digital camera as claimed in claim 7, wherein said display
device switches over its screen in response to an operation on an
operating device, to display the captured images one by one.
10. A digital camera as claimed in claim 5, wherein said display
device displays at least one of the captured images immediately
after the successive shots of one series are made.
11. A digital camera as claimed in claim 5, wherein said display
device displays at least one of the captured images, after image
data obtained by the successive shots of one series are written
in a storage medium.
12. A digital camera as claimed in claim 1, wherein said digital
camera is provided with a slow synchronized flash function, whereby
a flash shot is made at a slower shutter speed than usual in a standard
shooting mode, and wherein said slow synchronized flash function
is deactivated in said successive shooting mode.
13. A digital camera as claimed in claim 1, further comprising
a warning device for giving warning when it is judged to be necessary
to warn about one or both of the non-flash shot and the flash shot
in said successive shooting mode.
14. A digital camera as claimed in claim 13, wherein said warning
device totally displays data indicating the content of warnings
about any of the successive shots of one series.
15. A digital camera as claimed in claim 13, wherein said warning
device individually displays data indicating the content of warnings
about each of the successive shots of one series.
16. A digital camera as claimed in claim 13, wherein at least one
of the warning data and the exposure condition is displayed immediately
after the first shot, after every shot or after the last shot of
the successive shots of one series in said successive shooting mode.
17. A digital camera as claimed in claim 1, further comprising
a display device that display data on exposure conditions of the
respective successive shots of one series immediately after said
exposure condition deciding device decides the exposure conditions
in said successive shooting mode.
18. A digital camera as claimed in claim 1, wherein additional
data discriminating between the non-flash shot and the flash shot
are attached to the image data obtained by the respective shots
in said successive shooting mode.
19. A digital camera as claimed in claim 1, wherein common additional
data is attached to the image data obtained by the same series of
the successive shots.
20. A digital camera as claimed in claim 1, wherein said imaging
device first makes tentative non-flash and flash shots at a low
resolution, and thereafter makes the successive shots of one series
at a higher resolution in said successive shooting mode.
21. A digital camera as claimed in claim 20, further comprising
a display device for displaying preview images based on image data
obtained by the tentative shots, and a warning device that judges
on necessity of warning about the successive shots, and makes said
display device to display necessary warnings together with the corresponding
preview images.
22. A digital camera as claimed in claim 1, further comprising
a light control device for controlling volume of the flash light
from said flash device, wherein said flash device makes a pre-emission
with a first light volume, and said light control device calculates
a second light volume during the pre-emission, so said flash device
emits the flash light with the second light volume at the flash
shot of the successive shots in said successive shooting mode.
23. A digital camera as claimed in claim 22, wherein said pre-emission
doubles as a light emission for red-eye reduction.
24. A digital camera provided with a special successive shooting
mode wherein an imaging device makes a series of successive shots
upon each shutter release operation, including at least a non-flash
shot and at least a flash shot that is made synchronously with a
flash light from a flash device, said digital camera comprising:an
exposure condition deciding device for deciding exposure condition
of said imaging device through photometry and calculation, wherein
said exposure condition deciding device decides individual exposure
conditions for the non-flash shot and the flash shot upon a shutter
button being pressed halfway in said successive shooting mode, and
said imaging device starts the successive shots of one series when
said shutter button is fully pressed.
25. A digital camera as claimed in claim 24, further comprising
a light control device for controlling volume of the flash light
from said flash device, said light control device being successively
driven upon a predetermined operation or at predetermined timing
while said imaging device is being driven successively in said successive
shooting mode.
26. A digital camera as claimed in claim 25, further comprising
a device for changing imaging sensitivity of said imaging device,
wherein when a plural number of flash shots are successively made
upon one shutter release operation in said successive shooting mode,
the imaging sensitivity is raised and said light control device
is activated for these flash shots.
27. A digital camera as claimed in claim 24, further comprising
a device for changing imaging sensitivity of said imaging device,
wherein the imaging sensitivity when under-exposure will occur under
the exposure condition decided based on the present sensitivity
in said successive shooting mode.
28. A digital camera as claimed in claim 24, further comprising
a judging device for judging whether to lower photometric sensitivity
and imaging sensitivity when a measured subject brightness value
is above a predetermined value, wherein when said judging device
judges to lower the photometric sensitivity and imaging sensitivity,
said exposure condition deciding device carries out the photometry
and calculation at the lowered photometric and imaging sensitivities
to decide the exposure conditions, and said imaging device makes
the successive shots at the lowered imaging sensitivity.
29. A digital camera as claimed in claim 28, wherein when said
judging device judges not to lower the photometric sensitivity and
imaging sensitivity, said exposure condition deciding device decides
a common exposure condition to the non-flash and flash shots at
a standard photometric and imaging sensitivities in said successive
shooting mode.
30. A digital camera as claimed in claim 24, wherein the non-flash
shot is made before the flash shot among of the successive shots
of one series.
31. A digital camera as claimed in claim 24, wherein the flash
shot is made before the non-flash shot among of the successive shots
of one series.
32. A digital camera as claimed in claim 24, wherein a shot to
be made at a higher shutter speed is made before a shot to be made
at a lower shutter speed among of the successive shots of one series.
33. A digital camera as claimed in claim 24, further comprising
a device for changing imaging sensitivity of said imaging device,
wherein said exposure condition deciding device decides to use a
higher imaging sensitivity for a preceding one of the successive
shots of one series, and a lower imaging sensitivity for a succeeding
one of the successive shots of one series.
34. A digital camera as claimed in claim 24, further comprising
a warning device for giving warning when it is judged to be necessary
to warn about one or both of the non-flash shot and the flash shot
in said successive shooting mode.
35. A digital camera as claimed in claim 34, wherein said warning
device totally displays data indicating the content of warnings
about any of the successive shots of one series.
36. A digital camera as claimed in claim 34, wherein said warning
device individually displays data indicating the content of warnings
about each of the successive shots of one series.
37. A digital camera as claimed in claim 36, wherein the warning
data is displayed together with data of the exposure condition for
each shot.
38. A digital camera as claimed in claim 34, wherein at least one
of the warning data and the exposure condition is displayed immediately
after the first shot, after every shot or after the last shot of
the successive shots of one series in said successive shooting mode.
39. A digital camera as claimed in claim 34, wherein at least one
of the warning data and the exposure condition is displayed with
respect to a preceding one of the successive shots of one series
before said imaging device starts these successive shots.
40. A digital camera as claimed in claim 34, wherein at least one
of the warning data and the exposure condition is displayed before
said imaging device starts the successive shots of one series, with
respect to one be made at the slowest shutter speed of the successive
shots.
41. A digital camera as claimed in claim 24, wherein said imaging
device first makes tentative non-flash and flash shots at a low
resolution, and thereafter makes the successive shots at a higher
resolution in said successive shooting mode.
42. A digital camera as claimed in claim 41, further comprising
a display device for displaying preview images based on image data
obtained by the tentative shots, and a warning device that judges
on necessity of warning about the successive shots, and makes said
display device to display necessary warnings simultaneously with
said preview images.
43. A digital camera as claimed in claim 24, further comprising
a light control device for controlling volume of the flash light
from said flash device, wherein said flash device emits a first
light with a first volume at said tentative flash shot in said successive
shooting mode, and said light control device calculates a second
light volume based on a photometric value obtained through said
tentative flash shot, so said flash device emits the flash light
with the second light volume at the flash shot of the successive
shots.
44. A digital camera as claimed in claim 41, wherein said exposure
condition deciding device decides the exposure conditions for the
non-flash shot and the flash shot of the successive shots of one
series, based on data obtained through said tentative non-flash
and flash shots.
45. A digital camera as claimed in claim 24, further comprising
a display device for displaying images based on image data obtained
through said imaging device, wherein said display device displays
images as captured by the successive shots of one series in said
successive shooting mode.
46. A digital camera as claimed in claim 45, wherein said display
device displays the images as captured by the successive shots of
one series, simultaneously on a screen.
47. A digital camera as claimed in claim 45, wherein said display
device displays the images as captured by the successive shots of
one series, one by one on a screen.
48. A digital camera as claimed in claim 45, wherein said display
device displays at least one of the captured images immediately
after the successive shots of one series are made.
49. A digital camera as claimed in claim 45, wherein said display
device displays at least one of the captured images, after image
data obtained by the successive shots of one series are written
in a storage medium.
50. A digital camera as claimed in claim 24, wherein said digital
camera is provided with a slow synchronized flash function, whereby
a flash shot is made at a slower shutter speed than usual in a standard
shooting mode, and wherein said slow synchronized flash function
is deactivated in said successive shooting mode.
51. A digital camera as claimed in claim 24, further comprising
a display device that display data on exposure conditions of the
respective successive shots of one series immediately after said
exposure condition deciding device decides the exposure conditions.
52. A digital camera as claimed in claim 24, wherein additional
data discriminating between the non-flash shot and the flash shot
are attached to the respective image data obtained by the successive
shots of one series.
53. A digital camera as claimed in claim 24, wherein common additional
data is attached to the image data obtained by the same series of
the successive shots.
Digital Camera Patent Description
FIELD OF THE INVENTION
[0001]The present invention relates to a digital camera that can
shoot images of the same subject with flash and without flash in
continuous succession upon a shutter release operation.
BACKGROUND OF THE INVENTION
[0002]There are a wide variety of digital cameras, including compact
type, single-reflex type, and ones incorporated into electronic
equipments, like a camera phone. According to the types, the digital
cameras have various functions. For example, there are such single-reflex
type digital cameras that have a function to perform successive
shots in response to a shutter release operation, some of which
can emit flash light synchronously with each shot, as disclosed
for example in Japanese Laid-open Patent Application No. 2005-284166.
[0003]The above-mentioned prior art discloses a digital still camera
and a method of controlling the successive shots, wherein the amount
of flash light that is necessary for a proper exposure condition
is calculated based on a subject distance, a stop aperture value
and an imaging sensitivity of an imaging device. During the successive
shots, it is checked if a flash device can emit the calculated necessary
amount of flash light, considering how much voltage is charged in
a main capacitor and other flashing conditions. So long as the flash
device can emit the necessary amount of light, the camera performs
flash shots. After it becomes impossible to emit the necessary amount
of flash light, the camera continues shooting while adjusting the
stop aperture value, the shutter speed and/or the imaging sensitivity
so as to set a proper exposure condition under an available amount
of light.
[0004]According to the prior art, however, the choice between flash
shot and non-flash shot is made during the successive shots depending
upon the voltage charged in the main capacitor and the like, and
the user cannot make that choice. Besides, it is difficult to judge
which is preferable for an individual scene using the flash light
or not, unless the user checks the obtained images. Therefore, it
is desirable to make both a flash shot and a non-flash shot to one
scene, so that the user may compare them afterward.
SUMMARY OF THE INVENTION
[0005]In view of the foregoing, a primary object of the present
invention is to provide a digital camera that can make a flash shot
and a non-flash shot successively to one scene while setting proper
exposure conditions, and allows comparison between images as obtained
through the flash shot and the non-flash shot.
[0006]According to the present invention, in a digital camera that
is provided with a special successive shooting mode wherein an imaging
device makes a series of successive shots upon each shutter release
operation, including at least a non-flash shot and at least a flash
shot that is made synchronously with a flash light from a flash
device, the digital camera comprises an exposure condition deciding
device for deciding exposure condition of the imaging device through
photometry and calculation, wherein the exposure condition deciding
device decides a common exposure condition to the non-flash shot
and the flash shot in the successive shooting mode.
[0007]The exposure condition deciding device may alternatively
decide individual exposure conditions for the non-flash shot and
the flash shot upon a shutter button being pressed halfway in the
successive shooting mode, and the imaging device starts the successive
shots of one series when the shutter button is fully pressed.
[0008]Preferably, the digital camera further comprises a light
control device for controlling volume of the flash light from the
flash device, the light control device being successively driven
upon a predetermined operation or at predetermined timing while
the imaging device is being driven successively in the successive
shooting mode.
[0009]Preferably, the digital camera further comprises a device
for changing imaging sensitivity of the imaging device when under-exposure
will occur under the exposure condition decided based on the present
sensitivity in the successive shooting mode.
[0010]When a plural number of flash shots are successively made
upon one shutter release operation in the successive shooting mode,
it is preferable to raise the imaging sensitivity and activate the
light control device for these flash shots.
[0011]Preferably, the digital camera further comprises a judging
device for judging whether to lower photometric sensitivity and
imaging sensitivity when a measured subject brightness value is
above a predetermined value, wherein when the judging device judges
to lower the photometric sensitivity and imaging sensitivity, the
exposure condition deciding device carries out the photometry and
calculation at the lowered photometric and imaging sensitivities
to decide the exposure conditions, and the imaging device makes
the successive shots at the lowered imaging sensitivity.
[0012]Preferably, the digital camera further comprises a display
device for displaying images based on image data obtained through
the imaging device, wherein the display device displays images as
captured by the successive shots of one series in the successive
shooting mode.
[0013]Preferably, the digital camera further comprises a warning
device for giving warning when it is judged to be necessary to warn
about one or both of the non-flash shot and the flash shot in the
successive shooting mode.
[0014]According to a preferred embodiment, the imaging device of
the digital camera first makes tentative non-flash and flash shots
at a low resolution, and thereafter makes the successive shots of
one series at a higher resolution in the successive shooting mode.
Thereby, it becomes possible to display preview images based on
image data obtained by the tentative shots. It is preferable to
display necessary warnings together with the corresponding preview
images.
[0015]Where the digital camera comprises a light control device
for controlling volume of the flash light from the flash device,
the flash device emits a first light with a first volume at the
tentative flash shot in the successive shooting mode, and the light
control device calculates a second light volume based on a photometric
value obtained through the tentative flash shot, so the flash device
emits the flash light with the second light volume at the flash
shot of the successive shots.
[0016]Based on data obtained through the tentative non-f lash and
flash shot, the exposure condition deciding device preferably decides
the exposure conditions for the non-flash shot and the flash shot
of the successive shots of one series.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017]The above and other objects and advantages of the present
invention will be more apparent from the following detailed description
of the preferred embodiments when read in connection with the accompanied
drawings, wherein like reference numerals designate like or corresponding
parts throughout the several views, and wherein:
[0018]FIG. 1 is a front perspective view of a digital camera embodying
the present invention;
[0019]FIG. 2 is a rear perspective view of the digital camera;
[0020]FIG. 3 is a block diagram illustrating a schematic structure
of the digital camera;
[0021]FIG. 4 is a diagram illustrating a program for automatic
exposure control, according to a first embodiment of the present
invention;
[0022]FIG. 5 is a flow chart illustrating a main sequence for operating
the digital camera in a successive shooting mode, according to the
first embodiment;
[0023]FIGS. 6A and 6B are explanatory diagrams illustrating an
embodiment of a display screen for checking images captured in the
successive shooting mode;
[0024]FIG. 7 is an explanatory diagram illustrating another embodiment
of a display screen for checking images captured in the successive
shooting mode;
[0025]FIG. 8 is an explanatory diagram illustrating still another
embodiment of a display screen for checking images captured in the
successive shooting mode;
[0026]FIGS. 9A and 9B are diagrams illustrating programs for automatic
exposure control for a non-flash shot and a flash shot, according
to a second embodiment of the invention;
[0027]FIG. 10 is a flow chart illustrating a main sequence for
operating the digital camera in the successive shooting mode, according
to the second embodiment of the invention;
[0028]FIGS. 11A and 11B are diagrams illustrating programs for
automatic exposure control for a non-flash shot and a flash shot,
according to a third embodiment of the invention;
[0029]FIG. 12 is a flow chart illustrating a main sequence for
operating the digital camera in the successive shooting mode, according
to the third embodiment of the invention;
[0030]FIG. 13 is a diagram illustrating a program for automatic
exposure control, according to a fourth embodiment of the invention;
[0031]FIG. 14 is a flow chart illustrating a main sequence for
operating the digital camera, according to the fourth embodiment
of the invention;
[0032]FIG. 15 is a flow chart illustrating a sub-sequence for judging
whether to lower sensitivity or not, according to the fourth embodiment
of the invention;
[0033]FIG. 16 is a flow chart illustrating a sequence of a warning-display
process, according to a fifth embodiment of the invention;
[0034]FIG. 17 is an explanatory diagram illustrating an example
of a warning display screen according to the fifth embodiment of
the invention;
[0035]FIGS. 18A and 18B are explanatory diagrams illustrating an
example of a file structure on storing image data in a memory card;
[0036]FIGS. 19A and 19B are explanatory diagrams illustrating another
example of a file structure on storing image data in a memory card;
[0037]FIG. 20 is a block diagram illustrating a schematic structure
of a digital camera according to a sixth embodiment of the present
invention;
[0038]FIG. 21 is a flow chart illustrating a main sequence for
operating a digital camera, according to a seventh embodiment of
the invention;
[0039]FIG. 22 is an explanatory diagram illustrating an example
of a display screen for displaying exposure condition data and warning
data about both of first and second shots;
[0040]FIG. 23 is an explanatory diagram illustrating another example
of a display screen for displaying exposure condition data and warning
data about both of first and second shots;
[0041]FIG. 24 is an explanatory diagram illustrating an example
of a display screen where exposure condition data and warning data
are displayed about only one of successive shots;
[0042]FIGS. 25A and 25B are explanatory diagrams illustrating an
example of display screen which displays exposure condition data
and warning data about one shot, and thereafter those on the next
shot in the successive shooting mode.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0043]FIGS. 1 and 2 show an outer appearance of a digital camera
10 embodying the present invention. The digital camera 10 has a
substantially parallelepiped camera body 11 that is provided with
a taking lens 12 and a flash device 13 on its front. On a rear side
of the camera body 11 is mounted an LCD panel 15 as an image display
device. As will be described with reference to FIG. 3, a touch panel
19 is mounted on an obverse surface of the LCD panel 15. The camera
body 11 has on its top a release button 16, a power switch 17, and
a mode selection dial 18. According to the present embodiment, a
user can press the release button 16 into a half-pressed position
and then to a full-pressed position. Although it is not shown in
the drawings, a memory card slot is provided in a bottom of the
camera body 11, for detachably attaching a memory card 51 (see FIG.
3) to the digital camera 10, so that the memory card 51 stores image
data captured by the digital camera 10.
[0044]Responsive to an operation on the mode selection dial 18,
the digital camera 10 is switched over between a standard shooting
mode, a successive shooting mode, a reproduction mode for displaying
captured images on the LCD panel 15, and other modes. After the
mode selection, the digital camera 10 is operated through the touch
panel 19, except the operation on the shutter button 16 and the
power switch 17.
[0045]In synchronism with a shutter release operation that is executed
when the shutter button 16 is fully pressed, the flash device 13
emits a flash of light toward a subject, to make a flash shot. The
amount of flash light is decided depending upon a subject distance,
an imaging sensitivity and a stop aperture value, so as to make
a proper exposure amount. In the standard shooting mode, the flash
device 13 automatically emits light to a subject whose brightness
is less than a predetermined level, but does not automatically emit
light to a subject whose brightness is above the predetermined level.
The user can also decide whether to emit the flash light or not
in the standard shooting mode, regardless of the subject brightness.
[0046]When the successive shooting mode is selected, a series of
shots are made in continuous succession upon the shutter button
16 being fully pressed down. In the present invention, the successive
shooting mode means a specific successive shooting mode wherein
at least a non-flash shot, i.e. a shot without the flash light,
and at least a flash shot with the flash light, are made upon each
shutter release operation. In a first embodiment of the invention,
the digital camera 10 first makes a non-flash shot and next a flash
shot upon each shutter release operation, as set forth in detail
later
[0047]Referring to FIG. 3, a CPU 21 controls respective components
of the digital camera 10 through an I/O bus 23, in response to various
operational signals entered through the shutter button 16, the power
switch 17 and the touch panel 19.
[0048]The taking lens 12 is a zoom lens system consisting of lens
elements 26 and a stop 27. The lens elements 26 are driven by a
lens drive mechanism 28 including a stepping motor, to adjust the
optical zoom rate and the focal point of the zoom lens 12.
[0049]The stop 27 is driven by a stop drive mechanism 29 including
a stepping motor, to change the aperture value of the stop 27 stepwise.
For example, where the stop 27 has an f-number of F/2.8 at the open
aperture, and an f-number of F/11 at the minimum aperture, the stop
27 is set at one of F/2.8, F/4, F/5.6, F/8 and F/11, which correspond
to aperture values of 3.0, 4.0, 5.0, 6.0 and 7.0, respectively.
The lens drive mechanism 28 and the stop drive mechanism 29 are
respectively driven by motor drivers 31 and 32 under the control
of the CPU 21.
[0050]A solid state imaging device, e.g. a CCD 35, is placed behind
the taking lens 12. The CCD 35 is connected to the CPU 21 via a
timing generator (TG) 36. In the shooting modes, the CPU 21 controls
the timing generator 36 to generate a timing signal consisting of
clock pulses, so the CCD 35 is driven by the timing signal.
[0051]An optical image is formed through the taking lens 12 on
a light receiving surface of the CCD 35, so the CCD 35 converts
the optical image into an analog image signal. The image signal
is sent from the CCD 35 to a correlated double sampling (CDS) circuit
37, which outputs image signal of three primary colors (R, G, B)
in correspondence with respective amounts of electrostatic charges
in individual cells of the CCD 35. The analog three color image
signals output from the CDS circuit 37 are amplified by an amplifier
(AMP) 38, and are converted through an A/D converter 39 into digital
image data.
[0052]The image data is output from the A/D converter 39 to an
image input controller 41. The image input controller 41 is connected
to the CPU 21 via the I/O bus 23, and the I/O bus 23 is connected
to an internal memory 43, e.g. a synchronous dynamic random access
memory (SDRAM). So the CPU 21 controls the image input controller
41 to write the image data in the internal memory 43. The image
data, as stored in the internal memory 43, is processed by an image
signal processor circuit 46 for gradation conversion, white-balance
correction, gamma correction and the like.
[0053]In the shooting modes, the CCD 35 carries out an imaging
process at a given frame rate, and the obtained image data is processed
as above. Based on the processed image data, live image of the subject,
or may be called camera-through image, is displayed on the LCD panel
15. The LCD panel 15 is driven by an LCD driver 48. The LCD driver
48 is provided with an image memory and a D/A converter, to store
the processed image data temporarily in the image memory and then
converts the image data through the D/A converter into an analog
signal, e.g. NTSC signal. Then the LCD driver 48 outputs the NTSC
signal to the LCD panel 15.
[0054]When the shutter release operation is made by pressing the
shutter button 16 to the full, the CCD 35 captures true image data
of bigger pixel numbers than the image data for the live image.
The true image data is processed in the same way as set forth above,
and then compressed according to a predetermined compression format,
e.g. JPEG-format, through a compander circuit 49. A media controller
50 writes the compressed true image data in the memory card 51.
[0055]Besides the media controller 50, the compander circuit 49,
the LCD driver 48 and the image signal processor circuit 46, an
automatic exposure control (AE) circuit 53, an automatic focusing
(AF) circuit 49 and a flash memory 55 are connected to the I/O bus
23. The AF circuit 54 extracts high frequency contrast data from
the image data as being output from the image input controller 41,
and sends the contrast data to the CPU 21. With reference to the
contrast data, the CPU 21 controls the lens drive mechanism 28 through
the motor driver 27, to move a focusing lens along an optical axis.
The focusing lens is included in the lens elements 26, and stopped
at a position where the contrast of the high frequency component
of the subject image becomes the highest.
[0056]The AE circuit 53 integrates luminance signal of the image
data, to detect an integrated luminance value as photometric data
that is representative of a brightness value of the subject. The
AE circuit 53 also detects what kind of light source is used at
present, and sends the luminance value or subject brightness value
and the information on the light source to the CPU 21. Based on
the subject brightness value, the CPU 21 decides a proper exposure
condition, as a combination of a stop aperture value, a shutter
speed, and an imaging sensitivity. Then, the CPU 21 controls the
stop drive mechanism 29 through the motor driver 32, to set the
decided aperture value at the stop 27, and controls the timing generator
36 to generate such timing signal that activates the CCD 35 at the
decided shutter speed. The CPU 21 also sets the decided imaging
sensitivity at the CDS circuit 37 and the amplifier 38.
[0057]On setting the exposure condition, the CPU 21 decides the
shutter speed, the stop aperture value and the imaging sensitivity
based on the subject brightness, with reference to an automatic
exposure control program that is previously stored in the flash
memory 55. Note that the flash memory 55 is a well known non-volatile
memory that stores various programs, various data and various parameters
for use in controlling the operations.
[0058]FIG. 4 shows an automatic exposure control program according
to the first embodiment, wherein the same exposure condition that
is decided based on the subject brightness is used for the non-flash
shot and the flash shot in the successive shooting mode. In the
first embodiment, the exposure condition is decided by the shutter
speed and the aperture value, while the imaging sensitivity is maintained
constant for the non-flash shot and the flash shot as well.
[0059]Now the operation of the digital camera 10 in the successive
Shooting mode of the first embodiment will be described with reference
to the flow chart of FIG. 5.
[0060]First, the power switch 17 is turned on (ST1: step 1), and
the LCD panel 15 is operated to select the successive shooting mode
(ST2: step 2). Then, the image data output from the image input
controller 41 is sent to the LCD driver 48, to display the live
image of the subject on the LCD panel 15 (ST3: step 3). Thus, the
LCD panel 15 functions as an electronic viewfinder, so the user
frames a scene while observing the live image on the LCD panel 15.
When the user presses the shutter button 16 halfway or lightly (ST4:
step 4), the AF circuit 54 executes an AF processing (ST5: step
5), and the AE circuit 53 executes an AE processing (ST6: step 6).
[0061]The AF circuit 54 extracts the high frequency contrast data
from the image data, and sends the contrast data to the CPU 21.
The CPU 21 controls the lens drive mechanism 28 through the motor
driver 27, to move the lens elements 26 to a position where the
contrast of the high frequency component of the subject image becomes
the highest.
[0062]The AE circuit 53 integrates the luminance signal of the
image data, and sends the integrated luminance value as a brightness
value of the subject to the CPU 21. Based on the subject brightness
value, the CPU 21 decides a proper exposure condition, as a combination
of a stop aperture value and a shutter speed, according to the program
60. In the example shown in FIG. 4, the subject brightness value
is 13Ev, so the shutter speed is decided to be Tv8 ( 1/250 sec.),
and the aperture value is decided to be Av5 (F/5.8). Then, the CPU
21 controls the stop drive mechanism 29 to set the decided aperture
value at the stop 27, and controls the timing generator 36 to activate
the CCD 35 at the decided shutter speed (ST7: step 7).
[0063]After confirming the live image on the LCD panel 15 (ST8:
step 8), the user presses the shutter button 16 farther from the
half-pressed position to the full-pressed position (ST9: step 9).
The moment the shutter button 16 is pressed to the full, the non-flash
shot is made first (ST10: step 10), and the imaging signal is read
out from the CCD 35 in a charge accumulation time corresponding
to the shutter speed set by the AE circuit 53. The imaging signal
from the CCD 35 is fed through the CDS circuit 37, the amplifier
38 and the A/D converter 39 to the image input controller 41, so
the image input controller 41 outputs image data. The image data
obtained by the non-flash shot is temporarily stored in the internal
memory 43. Next, the CPU 21 executes the flash shot by driving the
flash device 13 to emit a predetermined amount of light synchronously
with a second time of reading of the imaging signal from the CCD
35 in the charge accumulation time corresponding to the set shutter
speed (ST11: step 11). Image data obtained by the flash shot is
also stored temporarily in the internal memory 43, to complete the
flash shot. Then, the CPU 21 reads out the image data as captured
by the non-flash shot and the flash shot from the internal memory
43, to display post-view images on the LCD panel 15 based on the
captured image data (ST12: step 12). In the present embodiment,
the post-view images are displayed in the way as shown in FIGS.
6A and 6B. That is, the image 61 captured by the non-flash shot
is displayed first, and the image 62 captured by the flash shot
is displayed next. After displaying the captured images, the CPU
21 compresses the image data to reduce the data volume through the
compander circuit 49, and writes the compressed image data in the
memory card 51 through the media controller 50 (ST13: step 13).
It is alternatively possible to write the image data in the memory
card 51 while displaying the captured images. For example, the image
data of the image 61 captured by the non-flash shot is written in
the memory card 51 while the captured image 61 is displayed on the
LCD panel 15, and when the writing of the image data of the image
61 is completed, the LCD panel 15 switches to display the image
62 captured by the flash shot. While the image 62 is displayed,
the image data of the image 62 is written in the memory card 51.
Completion of writing of the image data obtained by the non-flash
and flash shots is the end of one successive shooting. Then, the
CPU 21 resets the LCD panel 15 to display the live image. The user
can make the successive shooting appropriate times by making the
shutter release operations the appropriate times during the successive
shooting mode.
[0064]Since the image data of the same subject is obtained by the
non-flash shot and the flash shot in succession upon one shutter
release operation, the user can compare the image captured by the
non-flash shot to one captured by the flash shot, to choose a better
one.
[0065]Although the post-view images 61 and 62 of the non-flash
shot and the flash shot are displayed one after another at predetermined
intervals in the first embodiment, it is possible to display both
of the images 61 and 62 on the same screen of the LCD panel 15,
as shown in FIG. 7, thereby to facilitate comparison between them.
It is also possible to display switching buttons 63a and 63b on
the LCD panel 15, to switch over between post-view images by operating
the buttons 63a and 63b on the touch panel 19. Another kind of switching
device is usable instead of the switching buttons 63a and 63b of
the touch panel 19.
[0066]In the first embodiment, the post-view images obtained by
the non-flash shot and the flash shot in the successive shooting
mode are displayed before the image data of these images are written
in the memory card 51. However, it is possible to display the post-view
images after the image data of these images are written in the memory
card 51. In that case, it is preferable to provide the touch panel
19 with such a button 65 that puts the screen back to the previous
condition, for example, a standby condition preparing for the next
shutter release operation, where the live image is displayed on
the LCD panel 15. Alternatively, the screen may be set back to the
previous condition automatically after the post-view images are
displayed for a predetermined time.
[0067]In the first embodiment, the non-flash shot and the flash
shot are made at the same exposure condition decided through the
AE processing upon the shutter button 16 being half-pressed in the
successive shooting mode. But the present invention is not limited
to this embodiment. In a second embodiment as set forth below, the
non-flash shot and the flash shot are made at different exposure
conditions from each other. A digital camera for the second embodiment
may have the same structure described in the first embodiment, so
the following description will use the same reference numerals as
used in the first embodiment, and will refer to merely those features
essential to the second embodiment.
[0068]In the second embodiment, a flash memory 55 stores automatic
exposure control programs 71 and 72, as shown in FIGS. 9A and 9B,
for the non-flash shot and for the flash shot respectively. On the
AE processing in the successive shooting mode, a CPU 21 reads the
programs 71 and 72, to decide proper exposure conditions for the
non-flash shot and the flash shot based on a subject brightness
value according to the programs 71 and 72, respectively.
[0069]Now the operation in the successive shooting mode of the
second embodiment will be described with reference to the flow chart
of FIG. 10.
[0070]First, a power switch 17 is turned on (ST1: step 1), and
the successive shooting mode is selected (ST2: step 2). Then, the
live image of the subject is displayed on the LCD panel 15 (ST3:
step 3). The user frames a scene while observing the live image
on the LCD panel 15. When the user presses a shutter release button
16 halfway (ST4: step 4), an AF circuit 54 executes an AF processing
(ST5: step 5), and an AE circuit 53 executes an AE processing (ST6:
step 6). The AE circuit 53 integrates the luminance signal of the
image data, and sends the integrated luminance value as a subject
brightness value to a CPU 21. The CPU 21 reads the programs 71 and
72 and decides proper exposure conditions for the non-flash shot
and the flash shot based on the subject brightness value. In the
example shown in FIGS. 9A and 9B, the subject brightness value is
8Ev, so the shutter speed is decided to be Tv5 ( 1/30 sec.), and
the aperture value is decided to be Av3 (F/2.8) according to the
program 71 for the non-flash shot. On setting the exposure condition
according to the program 72 for the flash shot, the subject brightness
value of 8Ev is so dark that there is no corresponding combination
of a shutter speed and an aperture value. Therefore, as the lightest
available exposure condition, a shutter speed of Tv6 ( 1/60 sec.)
and an aperture value of Av3 (F/2.8) are selected. Then, the CPU
21 controls a stop drive mechanism 29 to set the decided aperture
value at a stop 27, and controls a timing generator 36 to provide
the decided shutter speed (ST7: step 7). After confirming the live
image on the LCD panel 15 (ST8: step 8), the user presses the shutter
button 16 farther from the half-pressed position to the full-pressed
position (ST9: step 9).
[0071]The moment the shutter button 16 is pressed to the full,
the non-flash shot is made first (ST10: step 10) at the exposure
condition decided according to the program 71, and the image data
obtained by the non-flash shot is temporarily stored in the internal
memory 43. Next, the CPU 21 changes the shutter speed and the aperture
value to those values decided according to the program 72 for the
flash shot (ST11: step 11). Then, the CPU 21 executes the flash
shot while driving the flash device 13 to emit a predetermined amount
of light. Image data obtained by the flash shot is also stored temporarily
in the internal memory 43, to complete the flash shot (ST12: step
12). Then, the CPU 21 reads out the image data as captured by the
non-flash shot and the flash shot from the internal memory 43, to
display post-view images on the LCD panel 15 based on the captured
image data (ST13: step 13). After displaying the captured images,
the CPU 21 compresses the image data to reduce the data volume through
a compander circuit 49, and writes the compressed image data in
the memory card 51 through a media controller 50 (ST14: step 14).
[0072]Since image data of the same subject is successively captured
by the non-flash shot and the flash shot under proper exposure conditions
respectively, it becomes possible to capture the images of better
qualities than those achieved by the first embodiment.
[0073]In the first embodiment, the non-flash shot and the flash
shot are always made at the same imaging sensitivity. But the present
invention is not limited to this embodiment. In a third embodiment
as set forth below, the imaging sensitivity is changed depending
upon the subject brightness in the successive shooting mode. The
third embodiment is applicable to a digital camera that has the
same structure as described in the first embodiment, so the following
description will use the same reference numerals as used in the
first embodiment, and will refer to merely those features essential
to the third embodiment.
[0074]In the third embodiment, a flash memory 55 stores an automatic
exposure control programs 81 and 82 for the non-flash shot and for
the flash shot, as shown in FIGS. 11A and 11B. On the AE processing
in the successive shooting mode, a CPU 21 reads the programs 81
and 82, to decide proper exposure conditions for the non-flash shot
and the flash shot based on a subject brightness value according
to the programs 81 and 82, respectively. In the third embodiment,
the exposure condition is determined as a combination of a shutter
speed, an aperture value and an imaging sensitivity. As implied
by +Sv1, +Sv2 and +Sv3 in the programs 81 and 82, the imaging sensitivity
is gradually raised as the subject brightness becomes lower.
[0075]Now the operation in the successive shooting mode of the
third embodiment will be described with reference to the flow chart
of FIG. 12.
[0076]First, a power switch 17 is turned on (ST1: step 1), and
the successive shooting mode is selected (ST2: step 2). Then, the
live image of the subject is displayed on the LCD panel 15 (ST3:
step 3), so the user frames a scene while observing the live image
on the LCD panel 15. When the user presses a shutter release button
16 halfway (ST4: step 4), an AF circuit 54 executes an AF processing
(ST5: step 5), and an AE circuit 53 executes an AE processing (ST6:
step 6). The AE circuit 53 integrates the luminance signal of the
image data, and sends the integrated luminance value as a subject
brightness value to a CPU 21. The CPU 21 reads the programs 81 and
82 and decides proper exposure conditions for the non-flash shot
and the flash shot based on the subject brightness value. In the
example shown in FIGS. 11A and 11B, the subject brightness value
is 6Ev, so the shutter speed is decided to be Tv5 ( 1/30 sec.),
and the aperture value is decided to be Av3 (F/2.8) according to
the program 81 for the non-flash shot. On setting the exposure condition
for the flash shot according to the program 82, the subject brightness
value of 6Ev is so dark that there is no corresponding combination
of a shutter speed and an aperture value. Therefore, as the lightest
available exposure condition, a shutter speed of Tv6 ( 1/60 sec.)
and an aperture value of Av3 (F/2.8) are selected, and also the
imaging sensitivity Sv is raised one grade. Then, the CPU 21 controls
a stop drive mechanism 29 to set the decided aperture value at a
stop 27, the decided shutter speed at a timing generator 36, and
the decided imaging sensitivity at a CDS circuit 37 and the amplifier
38 (ST7: step 7). After confirming the live image on the LCD panel
15 (ST8: step 8), the user presses the shutter button 16 farther
from the half-pressed position to the full-pressed position (ST9:
step 9).
[0077]The moment the shutter button 16 is pressed to the full,
the non-flash shot is made first (ST10: step 10) at the exposure
condition decided according to the program 81, and the image data
obtained by the non-flash shot is temporarily stored in the internal
memory 43. Next, the CPU 21 changes the shutter speed, the aperture
value and the imaging sensitivity to those values decided according
to the program 82 for the flash shot (ST11: step 11). Then, the
CPU 21 executes the flash shot while driving the flash device 13
to emit a predetermined amount of light. Image data obtained by
the flash shot is also stored temporarily in the internal memory
43, to complete the flash shot (ST12: step 12). Then, the CPU 21
reads out the image data as captured by the non-flash shot and the
flash shot from the internal memory 43, to display post-view images
on the LCD panel 15 based on the captured image data (ST13: step
13). After displaying the captured images, the CPU 21 compresses
the image data to reduce the data volume through a compander circuit
49, and writes the compressed image data in the memory card 51 through
a media controller 50 (ST14: step 14).
[0078]Since image data of the same subject is successively captured
by the non-flash shot and the flash shot while changing the exposure
conditions, including the imaging sensitivity, it becomes possible
to capture the images of better qualities than those achieved by
the first and second embodiments.
[0079]In the first embodiment, photometric sensitivity and imaging
sensitivity are always maintained constant both for the non-flash
shot and the flash shot. In a fourth embodiment as set forth below,
the photometric sensitivity and the imaging sensitivity are changed
depending upon the subject brightness in the successive shooting
mode. The fourth embodiment is applicable to a digital camera that
has the same structure as described in the first embodiment, so
the following description will use the same reference numerals as
used in the first embodiment, and will refer to merely those features
essential to the third embodiment. In the fourth embodiment, a CPU
21 functions as a device that executes a judging process for deciding
whether to lower the sensitivity or not.
[0080]In the fourth embodiment, a flash memory 55 stores an automatic
exposure control program 91 for the non-flash shot and for the flash
shot, as shown in FIG. 13. On the AE processing in the successive
shooting mode, a CPU 21 reads the program 91, to decide proper exposure
conditions for the non-flash shot and the flash shot based on a
subject brightness value according to the program 91. As shown in
FIG. 13, the program 91 includes three kinds of programs indicated
by solid lines 91a, dashed lines 91b and chain-dotted lines 91c.
The program indicated by the solid lines 91a is used to decide the
exposure condition for the non-flash and flash shots while the subject
brightness is in a lower range. On the other hand, the programs
indicated by the dashed lines 91b and the chain-dotted lines 91c
are used to decide the exposure condition while the subject brightness
is in a higher range, wherein the program 91b is for the non-flash
shot, and the program 91c is for the flash shot. Note that ISO sensitivity
is used for setting the photometric sensitivity and the imaging
sensitivity.
[0081]Now the operation in the successive shooting mode of the
fourth embodiment will be described with reference to the flow chart
of FIGS. 14 and 15.
[0082]First, a power switch 17 is turned on (ST1: step 1), and
the successive shooting mode is selected (ST2: step 2). Then, the
live image of the subject is displayed on the LCD panel 15 (ST3:
step 3), so the user frames a scene while observing the live image
on the LCD panel 15. When the user presses a shutter release button
16 halfway (ST4: step 4), the CPU 21 executes the judging process
(ST5: step 5) for deciding whether to lower the sensitivity or not,
as shown in FIG. 15. First, it is checked whether automatic setting
of the ISO sensitivity is selected or a fixed value is selected
as the ISO sensitivity (ST101: step 101). If the ISO sensitivity
is fixed, the fixed value is used without lowering the sensitivity.
If the automatic setting selected, the CPU 21 checks if the live
image is displayed on an LCD panel 15 (ST102: step 102), and extracts
the last frame of the displayed live image, to send the last frame
to an AE circuit 53 (ST103: step 103). If the live image is not
displayed, the judging process for lowering the sensitivity is terminated.
The AE circuit 53 integrates luminance signals of the extracted
frame, and sends the integrated luminance value as a tentative subject
brightness value to the CPU 21 (ST104: step 104). The CPU 21 compares
the tentative subject brightness value with a predetermined value
(ST105: step 105). If the tentative subject brightness value is
less than the predetermined value, the CPU 21 calculates a sensitivity
lowering value according to the tentative subject brightness value
(ST106: step 106). Then, the calculated sensitivity lowering value
is compared with a second predetermined value (ST107: step 107).
If the sensitivity lowering value is not less than the second predetermined
value, the photometric sensitivity and the imaging sensitivity are
decided to be lowered (ST108: step 108). If the sensitivity lowering
value is less than the second predetermined value, the photometric
sensitivity and the imaging sensitivity are kept Unchanged (ST109:
step 109). Thus, the judging process is concluded.
[0083]When the judging process is concluded, an AF circuit 54 executes
an AF processing (ST6: step 6), and an AE circuit 53 executes an
AE processing (ST7: step 7). The AE circuit 53 integrates the luminance
signal of the image data, and sends the integrated luminance value
as a subject brightness value to the CPU 21. If the sensitivity
is decided to be lowered in the preceding judging process, the CPU
21 drives a timing generator 36, a CDS circuit 37 and an amplifier
38 so as to lower the photometric sensitivity by the decided sensitivity
lowering value. Then, the CPU 21 reads the program 91 and decides
proper exposure conditions for the non-flash shot and the flash
shot based on the subject brightness value. At that time, if the
sensitivity lowering value is not set up in the previous judgment
process, the CPU 21 decides the exposure condition according to
the solid lines 91a, and applies this exposure condition to both
the non-flash shot and the flash shot. If, on the other hand, the
sensitivity lowering value is set up in the previous judgment process,
the CPU 21 controls the timing generator 36, the CDS circuit 37
and the amplifier 38 to lower the photometric sensitivity and the
imaging sensitivity. At the same time, the CPU 21 switches to decide
the exposure condition for the non-flash shot according to the dashed
lines 91b, and the exposure condition for the flash shot according
to the chain-dotted lines 91c. Then, the CPU 21 sets the exposure
condition as decided according to the program 91a or the program
91b (ST8: step 8). After confirming the live image on the LCD panel
15 (ST9: step 9), the user presses the shutter button 16 farther
from the half-pressed position to the full-pressed position (ST10:
step 10).
[0084]The moment the shutter button 16 is pressed to the full,
the non-flash shot is made first (ST11: step 11) at the exposure
condition decided according to the program 91a or 91b, and the image
data obtained by the non-flash shot is temporarily stored in the
internal memory 43. Next, if the sensitivity lowering value is set
up, the CPU 21 changes the shutter speed and the aperture value
to those values decided according to the program 91c for the flash
shot (ST12: step 12). If not, the same exposure condition is used
for the flash shot as for the non-flash shot. Then, the CPU 21 executes
the flash shot while driving the flash device 13 to emit a predetermined
amount of light. Image data obtained by the flash shot is also stored
temporarily in the internal memory 43, to complete the flash shot
(ST13: step 13). Then, the CPU 21 reads out the image data as captured
by the non-flash shot and the flash shot from the internal memory
43, to display post-view images on the LCD panel 15 based on the
captured image data (ST14: step 14). After displaying the captured
images, the CPU 21 compresses the image data to reduce the data
volume through a compander circuit 49, and writes the compressed
image data in the memory card 51 through a media controller 50 (ST15:
step 15).
[0085]Since the photometric sensitivity and the imaging sensitivity
are changed according to the subject brightness in the successive
shooting mode, and the exposure conditions for the non-flash shot
and the flash shot are decided while considering the sensitivity,
it becomes possible to capture the images of better qualities than
those achieved by the first or second embodiment. Note that, if
the sensitivity lowering results that the exposure condition decided
by photometry and calculation will make an under-exposed image even
with the open-aperture, it is possible to raise the sensitivity.
In that case, it is possible to change the photometric sensitivity
or the imaging sensitivity between the non-flash shot and the flash
shot.
[0086]Although the imaging sensitivity of the CCD 35 is changed
depending upon the calculation results for setting the exposure
condition in the fourth embodiment, it is alternatively possible
to change the imaging sensitivity one shot after another without
executing the above-described judging process or calculation. Then
the time lag between the successive shots is reduced.
[0087]Now a fifth embodiment of the present invention will be described.
In the fifth embodiment, if an error can occur in the successive
shooting mode, a corresponding warning is given to the user before
shooting. The fifth embodiment is applicable to a digital camera
that has the same structure as described in the first embodiment,
except that a CPU 21 functions as a device for judging whether to
give a warning or not. Therefore, the same reference numerals as
used in the first embodiment will be used for the same parts of
the digital camera in the following description. Corresponding to
a variety of errors, many kinds of warnings are prepared, e.g. a
warning that notices a flash emission, a warning of hand-shake,
a warning of under-exposure, and a warning of out-of-focus. The
judgment for the warning is done upon a shutter release button 16
being pressed halfway, i.e. simultaneously with the AE and AF processing.
For example, the hand-shake warning is given when there are large
differences between frames of the live image. The under-exposure
warning is given when the subject brightness is so dark that the
exposure amount will be insufficient even under the lightest available
exposure condition. The out-of-focus warning is given when the subject
distance is beyond a focusable range of the taking lens. The CPU
21 makes judgments for these warnings.
[0088]When the CPU 21 judges that a warning should be given, the
CPU 21 starts a warning display process for displaying the warning
on an LCD panel 15. As shown in the flow chart of FIG. 16, the CPU
21 deletes previous data on warning (ST201) at the start of the
warning display process. Next, if any warning is judged to be given
with respect to the non-flash shot or the flash shot, the warning
is set up to be displayed (ST202). The same process is carried out
with respect to all kinds of warnings (ST203). Then, the warnings
as being set up are displayed as marks 102a, 102b, 102c and 102d
together with a live image 100 on the LCD panel 15, as shown for
example in FIG. 17. In the example of FIG. 17, the marks 102a, 102b,
102c and 102d represent the flash emission warning, the hand-shake
warning, the out-of-focus warning and the under-exposure warning,
respectively. If any of these warnings should be given about the
non-flash shot or the flash shot, corresponding one or more of these
marks 102a to 102d are displayed commonly to the non-flash shot
and the flash shot. Since it is unnecessary to display the warning
marks individually about the non-flash shot and the flash shot,
it takes less area for displaying the warning marks. The user can
see at once from the displayed marks 102a to 102d what kinds of
warnings are given about the non-flash shot and the flash shot.
[0089]The LCD panel 15 may also display a mark 103 indicating that
the digital camera is in the successive shooting mode, on the same
screen as the warning marks 102a to 102d. In the example shown in
FIG. 17, the mark 103 consists of a mark 103a representative of
the non-flash shot and a mark 103b representative of the flash shot.
Beside these marks, information 104a on the exposure condition set
for the non-flash shot, e.g. the aperture value, the shutter speed,
and the imaging sensitivity, and information 104b on the exposure
condition set for the flash shot may be displayed. Instead of or
in addition to displaying the warning as marks, it is possible to
give the warnings as text or voice.
[0090]Where the digital camera has a slow synchronized flash function
in the standard shooting mode, i.e., the function to switch the
shutter speed to a slower value than usual and emit a flash light
synchronously with the slower shutter speed, it is preferable to
deactivate the slow synchronized flash function in the successive
shooting mode. Then, both the non-flash shot and the flash shot
are made without the danger of blurring, which could otherwise occur
at the slower shutter speed.
[0091]Beside the respective features of the above embodiments,
the image data captured by the respective shots in the successive
shooting mode is preferably stored in association with additional
information, such as data discriminating between the non-flash shot
and the flash shot, and data on the exposure condition, in a memory
card 51. FIGS. 18A and 18B show examples of image files 111 and
112 consisting of the image data 111a and 112a captured by the non-flash
shot and the flash shot, and the additional information 111b and
112b, respectively. For example, the additional information is Exif-format
data, and is written in an Exif-tag zone of the image data.
[0092]The content of the additional information is not limited
to the above embodiment. For example, as shown in FIGS. 19A and
19B, common additional information 115, such as date and time of
the successive shots and the like, is added to image data 113a and
114a as captured by the respective shots, to constitute image files
113 and 114 respectively. Since the image files 113 and 114 including
the common additional information 115 are stored in a memory card
51, it is easy for the user to identify those image data captured
successively upon one shutter release operation, when reviewing
the image data stored in the memory card 51.
[0093]In the above embodiments, a non-flash shot and then a flash
shot are made successively upon one shutter release operation in
the successive shooting mode. However, it is possible to make the
flash shot before the non-flash shot in the successive shooting
mode. Then the flash light notices the user and the subject of the
start of shooting. When the non-flash shot is made first, the time
lag necessary for achieving a sufficient volume of flash light becomes
relatively long. Making the flash shot first will therefore reduce
the time lag between the first shot and the next shot. It is also
possible to decide the sequence of making the non-flash shot and
the flash shot depending upon the exposure conditions decided by
the CPU 21. For example, one to be made at a higher shutter speed,
i.e. in a shorter exposure time, is made first between the non-flash
shot and the flash shot.
[0094]Furthermore, it is possible to make the non-flash shot or
the flash shot more than one time upon one shutter release operation
in the successive shooting mode. That is, in order to achieve the
above described effects, at least a non-flash shot and at least
a flash shot should be made upon one shutter release operation in
the successive shooting mode, to allow comparison between two kinds
of images of the same subject.
[0095]The present invention is also applicable to a digital camera
that is provided with an automatic flash device having a function
to control the volume of the flash light. FIG. 20 shows a sixth
embodiment applied to a digital camera 120 provided with an automatic
flash device 121 having the light volume control function. In FIG.
20, the same reference numerals designate the same parts as in the
first embodiment shown in FIG. 3, so the description of these parts
is omitted with respect to the sixth embodiment.
[0096]The automatic flash device 121 is constituted of a flash
circuit 122, a discharge tube 123, a light control circuit 124 and
a light control sensor 125. To make a flash shot, a control signal
is output from a CPU 21 to the automatic flash device 121, thereby
to charge a main capacitor of the flash circuit 122. Then, in synchronism
with the shutter release operation, a synchronizing signal is fed
to the flash circuit 122 and the light control circuit 124. Upon
the synchronizing signal, the flash circuit 122 discharges the main
capacitor through the discharge tube 123, so the discharge tube
emits a flash of light toward the subject. The light control sensor
125 detects light reflected from the subject, to output a luminance
signal corresponding to the luminance of the reflected light. When
the synchronizing signal is fed and a CCD 35 starts the exposure,
the light control circuit 124 receives and integrates the luminance
signal with time. When the integrated value reaches a predetermined
threshold value, the light control circuit 124 outputs a stop signal
to the flash circuit 122. Upon receipt of the stop signal, the flash
circuit 122 stops supplying electric current to the discharge tube
123, to stop the light emission.
[0097]According to the sixth embodiment, at least one non-flash
shot and plural times of flash shots are successively made upon
one shutter release operation in the successive shooting mode. Besides,
the CPU 21 controls the imaging sensitivity of the CCD 35 to be
higher for the flash shot than for the non-flash shot. With the
higher imaging sensitivity, the volume of the flash light from the
automatic flash device 121 can be reduced. It takes less time to
charge the main capacitor up to a necessary level for emitting the
flash light with the reduced volume, so the time lag between the
successive flash shots is reduced.
[0098]The timing when the automatic flash device 121 starts the
above-described light control is not limited to when a shutter release
button is pressed halfway or to the full, but may be anytime in
a period from immediately after the selection of the successive
shooting mode to the end of shooting. For example, the light control
may start at predetermined time intervals after the start of the
successive shooting mode, or in a predetermined time after a previous
shooting. The light control may also start upon an input signal
entered through an operation member other than the shutter button.
[0099]According to a seventh embodiment of the present invention,
a tentative shot is made before a final shot, and the light control
for the flash light is executed during the tentative shot, so as
to save time for the exposure control and the flash light control
during the final shot. Preferably, the tentative shot is set to
capture image data with a fewer number of pixels than image data
captured by the final shot. Thereby, it takes less time for the
tentative shots. The seventh embodiment is applicable to a digital
camera that has the same structure as the digital camera 120 shown
in FIG. 20, so the same reference numerals as used in the sixth
embodiment will be used in the seventh embodiment, while omitting
the description of the camera structure.
[0100]The operation of the seventh embodiment will be described
with reference to the flow chart of FIG. 21. First, a power switch
17 is turned on (ST1), and the successive shooting mode is selected
(ST2). Then, the live image of the subject is displayed on the LCD
panel 15 (ST3). When the user presses a shutter release button 16
halfway (ST4), a tentative non-flash shot and a tentative flash
shot are made (ST5, ST6). Note that a flash light may be emitted
immediately before these tentative shots, for the sake of preventing
red-eye phenomenon.
[0101]In the tentative non-flash shot (ST5), an AF processing and
an AE processing are executed without the flash light, to send a
CPU 21 an integrated luminance value and data on a focusing position
of a lens 26 where the highest contrast of the image is obtained.
Depending upon the received data, the CPU 21 decides an exposure
condition for the final non-flash shot. In the tentative flash shot
(ST6), a pre-emission of a flash light is done with a volume controlled
through an automatic flash device 121, and an integrated luminance
value as a subject brightness value, data on a focusing position
of the lens 26 where the highest contrast of the image is obtained,
and a luminance value detected by a light control sensor 125, i.e.
the luminance value of the reflected flash light, are sent to the
CPU 21. Based on these values, the CPU 21 decides an exposure condition
and a flash light volume for the final flash shot (ST7).
[0102]When the user confirms a live image (ST8) and presses the
shutter button 16 to the full (ST9), the CPU 21 makes the final
non-flash shot (ST10), while controlling the aperture value and
the shutter speed according to the exposure condition decided during
the tentative non-flash shot. In succession to this, the final flash
shot is made (ST11), while the CPU 21 changes the aperture value
and the shutter speed according to the exposure condition decided
during the tentative flash shot, and controls the automatic flash
device 121 to emit a flash light with the volume decided during
the tentative flash shot. Thereafter, images captured by the final
non-flash shot and the final flash shot are displayed as post-view
images on an LCD panel 15 (ST12), and image data of the captured
images are written in a memory card 51 (ST13). When a predetermined
number of successive shots are made in this way upon one shutter
release operation, a sequence of successive shooting is terminated.
[0103]Since the processing for flash light control and the calculation
for exposure control are carried out during the tentative shots
before the final shots, it is unnecessary to make the processing
for flash light control and the like during the final shots, so
the time lag between the final non-flash shot and the final flash
shot is reduced. Furthermore, the pre-emission of the flash light
for the tentative flash shot will make the user and the subject
aware of the start of shooting.
[0104]The pre-emission of the flash light for the tentative flash
shot may double as that for the red-eye reduction. Then, a sufficient
time for closing the iris is provided between the flash pre-emission
for the tentative flash shot and the flash emission for the final
flash shot, so the effect of red-eye reduction is enhanced. Moreover,
it is unnecessary to provide a specific device for emitting light
for the red-eye reduction, and the requisite number of times of
flash light emissions is reduced. Then, the consumption of batteries
in the digital camera will be reduced.
[0105]Although the LCD panel 15 merely displays the live image
before the final shots in the above embodiment, it is possible to
display images captured by the tentative non-flash and flash shots
as preview images on the LCD panel 15. Thereby, the user can preview
how the images will be captured, in advance to the final shots.
As the image data is captured with a fewer number of pixels, i.e.
at a lower resolution, by the tentative shot, the preview image
is displayed instantly. Then, image data is captured with a larger
number of pixels, i.e. at a higher resolution, by the final shot,
to obtain a high-definition image.
[0106]In the embodiment as set forth above with reference to FIGS.
16 and 17, warning data is displayed if a warning is to be given
with respect to the non-flash shot or the flash shot. But the present
invention is not limited to this embodiment. It is possible to display
warning data individually about each of the non-flash shot and the
flash shot. For example, as shown in FIG. 22, information on the
non-flash shot or a first shot may be displayed in an upper zone
as bounded by a dashed line 151a, whereas information on the flash
shot or a second shot may be displayed in a lower zone as bounded
by a dashed line 151b. In the information zone 151a for the non-flash
zone, data on an exposure condition 152a and warning marks 153a
and 153b are displayed. In the information zone 151b for the flash
zone, data on an exposure condition 152b and warning marks 153c
and 153d are displayed. Thus, the user is noticed of the exposure
condition and the warning with respect to each shot.
[0107]Although the warning data is displayed on the same screen
as the live image in the above embodiments, it is possible to display
the warning data in association with each preview image which may
be obtained by a tentative shot in the way as set forth above. For
example, as shown in FIG. 23, a fragment of an image obtained by
a first shot that may be a non-flash shot is displayed as a preview
image 155a in a corner of an LCD panel 15, whereas a fragment of
an image obtained by a second shot that may be a flash shot is displayed
as a preview image 155b in another corner of the LCD panel 15. Beside
these preview images 155a and 155b, data on exposure conditions
152a and 152b and warning marks 153a to 153d are displayed in the
same way as in the embodiment shown in FIG. 22. Thereby, the user
can check the information on the respective shots together with
their preview images.
[0108]It is also possible to display the warning data and the exposure
condition data with respect to a predetermined one, e.g. a first
one, of a series of successive shots. This embodiment needs a small
area for displaying the information, so a large area is usable for
displaying the live image or the preview image. The one shot, about
which the warning data and the exposure condition data is to be
displayed, may not necessarily be predetermined, but may be chosen
in an appropriate manner. For example, the exposure condition data
and the warning data may be displayed with respect to such a shot
that an exposure condition deciding device, e.g. a CPU 21, decides
to make at a slower shutter speed than others. This is because the
shot made at the slow shutter speed is more likely to be affected
by the hand-sake or the like. Alternatively, as shown in FIG. 24,
it is possible to display exposure condition data 157 about a shot
that is decided to be made at a slower shutter speed, and warning
marks 158a to 158d, each of which is to be given about at least
one of the successive shots, like in the fifth embodiment.
[0109]According to another embodiment shown in FIGS. 25A and 25B,
exposure condition data 161a and warning data 162a on a first shot
are displayed in a time period from the start of a series of successive
shots to the end of the first shot, as shown in FIG. 25A, and thereafter,
exposure condition data 161b and warning data 162b on a second shot
are displayed immediately after the first shot, as shown in FIG.
25B. Because only information on the following shot is displayed,
a small area is used for displaying the information, so a large
area is usable for displaying the live image or the preview image.
Where more than two shots are successively made upon a shutter release
operation, exposure condition data and warning data on a third shot
are displayed immediately after the second shot.
[0110]The timing of displaying the exposure condition data and
the warning data is not limited to the above embodiments. For example,
it is possible to display the information immediately after the
first shot, after every shot, or after the last shot of one series.
The exposure condition data and the warning data may also be displayed
immediately after an exposure condition deciding device, such as
a CPU 21, decides exposure conditions for the respective shots.
Thereby, the display on the screen is simplified before the decision
of the exposure conditions.
[0111]The exposure condition data and the warning data may be displayed
on a separate display device, instead of an LCD panel 15 of a digital
camera.
[0112]Thus, the present invention is not to be limited to the above
embodiments but, on the contrary, various modifications will be
possible without departing from the scope of claims appended hereto.
|