JP2005175908A - Electronic camera provided with auto bracketing function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To report an ISO sensitivity value to a photographer at all times during auto bracketing photographing in which the ISO sensitivity value is changed and to make it possible to change the ISO sensitivity value. <P>SOLUTION: An electronic camera is provided with: an image pickup means for picking up the image of an object; and an auto bracketing photographing mode for performing photographing in which the ISO sensitivity is changed automatically for two or more times (S203 to S216). The electronic camera is further provided with: a display means for displaying information relating to photographing; a setting means capable of setting the auto bracketing photographing mode; and a control means for performing control so as to display the value of the ISO sensitivity on the display means (S210) during the auto bracketing photographing when the auto bracketing photographing mode is set by the setting means. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electronic camera having an auto bracketing (stepwise exposure) function for performing continuous shooting while automatically changing ISO sensitivity and adjustment values for white balance adjustment.

  Conventionally, with still cameras using silver halide film, when it is difficult to determine the correct exposure, such as a scene at dusk or a scene with high-reflectance subjects, A so-called auto bracketing shooting is performed in which a plurality of frames are shot and an appropriately exposed frame is selected from the frames.

  Even when an electronic still camera using a CCD or the like is used as a photographing device, the circumstances regarding exposure are the same, and if photographing is performed with an inappropriate exposure amount, only a dark image or an image that is too bright can be obtained. In scenes where it is difficult to determine the exposure, auto bracketing is performed in the same way as a silver halide camera.

  In a camera having such an auto bracketing shooting mode, the shutter speed and the aperture value are usually displayed at all times. During auto bracketing shooting, the shutter speed or aperture value changes according to the bracketing amount (exposure correction amount) set by the photographer (either or both change depending on the camera mode). Since the shutter speed and aperture value are always displayed, you can check the shutter speed or aperture value even during bracketing shooting, and the photographer can check the change in shooting effect due to changes in the shutter speed and aperture value. You can shoot while.

  Also, as a technique peculiar to an electronic still camera, Japanese Laid-Open Patent Publication No. 11-4380 discloses a technique for performing auto bracketing shooting by automatically changing the ISO sensitivity value by changing the CCD gain and gamma characteristics. It is disclosed.

Further, Japanese Patent Application Laid-Open No. 2001-54013 discloses that auto bracketing shooting is performed by automatically changing a white balance adjustment value.
Japanese Patent Laid-Open No. 11-4380 JP 2001-54013 A

  In the case of the conventional example described above, the shutter speed or aperture value can be checked even during bracketing shooting, so the photographer can check the change in shooting effect due to changes in the shutter speed or aperture value. It was very convenient to shoot while taking pictures.

  However, in the case of auto bracketing photography that changes the ISO sensitivity and white balance adjustment value disclosed in Japanese Patent Laid-Open Nos. 11-4380 and 2001-54013, there are the following problems.

  Normally, ISO sensitivity and white balance adjustment values (usually color temperature) are displayed only in a mode that allows input, and when input is completed, the display goes off, and ISO sensitivity and white balance adjustment values are always displayed. There were few things.

  Therefore, when performing auto bracketing shooting that changes the ISO sensitivity and white balance adjustment value, the ISO sensitivity and color temperature values corresponding to the bracketing correction amount are not displayed, so the photographer changes during bracketing shooting. The ISO sensitivity and the color temperature value could not be confirmed, and the photographing effect could not be confirmed.

  For example, in the case of ISO sensitivity, noise usually increases on the high sensitivity side, and noise is conspicuous in shooting scenes such as night scenes. In such a case, the bracketing correction amount is reduced or the bracketing reference value is changed. There is a need.

  Also, when changing the white balance adjustment value, the color temperature during bracketing shooting is not known, so the photographer cannot recognize even if excessive correction is performed depending on the shooting scene. In some cases, shooting was not performed as intended.

  If a display device that always displays ISO sensitivity and color temperature is provided, the above problem can be solved. However, since a separate display device is required, the cost is increased and the camera is further increased in size.

  The above problem can also be solved by increasing the number of segments that always display ISO sensitivity and color temperature in the same display area. However, if the number of segments is simply increased in the same display area, the display becomes difficult to see. Further, if the display area is expanded, not only will the cost be increased, but there will be a problem that the camera will become larger.

  In addition, Japanese Patent Laid-Open Nos. 11-4380 and 2001-54013 do not describe the ISO sensitivity and color temperature display during auto bracketing shooting, and thus do not solve the above problems. .

  In order to achieve the above object, the present invention described in claim 1 is provided with an imaging unit that captures an image of a subject and an auto bracketing shooting mode that automatically performs shooting with the ISO sensitivity changed a plurality of times. In the electronic camera, display means for displaying information relating to shooting, setting means for setting the auto bracketing shooting mode, and when the auto bracketing shooting mode is set by the setting means, the display during auto bracketing shooting An electronic camera having an auto bracketing function provided with a control means for controlling the ISO sensitivity value to be displayed on the means.

  According to a second aspect of the present invention, in the electronic camera having the auto bracketing function according to the first aspect, when the auto bracketing shooting mode is set by the setting unit, the control unit is configured to An electronic camera having an auto bracketing function for controlling to change part of the information related to the normal photographing displayed on the display means to the ISO sensitivity value during the ketting photographing.

  Further, the present invention according to claim 3 is provided with an image pickup means for picking up an image of a subject and an auto bracketing shooting mode in which shooting with a change of an adjustment value for automatically adjusting white balance is performed a plurality of times. In the electronic camera, when the auto bracketing shooting mode is set by the display means for displaying information related to shooting, the setting means capable of setting the auto bracketing shooting mode, and the auto bracketing shooting mode by the setting means, An electronic camera having an auto bracketing function including control means for controlling the display means to display an adjustment value for white balance adjustment.

  According to a fourth aspect of the present invention, in the electronic camera having the auto bracketing function according to the third aspect, when the auto bracketing shooting mode is set by the setting unit, the control unit is configured to An electronic camera having an auto bracketing function for controlling to change a part of information related to normal photographing displayed on the display means to an adjustment value for white balance adjustment during ketting photographing.

  According to the first or third aspect of the present invention, the ISO sensitivity value and the white balance adjustment value are always displayed during the auto bracketing shooting for changing the ISO sensitivity value and the white balance adjustment value. When shooting is performed with an inappropriate ISO sensitivity value or white balance adjustment value, the photographer can change the ISO sensitivity value or white balance adjustment value.

  According to the present invention as set forth in claim 2 or 4, it is not necessary to add a new display means, a segment or the like in order to display the ISO sensitivity value or the white balance adjustment value. Increase in size and cost can be prevented.

  The best mode for carrying out the present invention is as described in Examples described later.

  Hereinafter, a single-lens reflex digital camera which is an embodiment of the present invention will be described in detail.

  In this embodiment, a detachable recording device is used as the recording means. However, the present invention is not limited to this, and can be similarly implemented by incorporating the recording device.

  1 and 2 show a single-lens reflex type digital camera which is an embodiment of the present invention.

  FIG. 1 is a top view showing the configuration of a single-lens reflex digital camera according to the present invention, and FIG. 2 is a rear view showing the configuration of the digital camera.

  1 and 2, reference numeral 100 denotes a camera body, 111 denotes an eyepiece window for finder observation, 112 denotes an AE (automatic exposure) lock button, and 113 denotes an AF (autofocus) distance measuring point selection button.

  Reference numeral 114 denotes a release button for performing a photographing operation, and the switch SW1 is turned on in the first stroke and the switch SW2 is turned on in the second stroke.

  Reference numeral 115 denotes a main electronic dial which is a first operation means. For example, a 2-bit signal having a phase difference of 90 ° is sent to a microcomputer (described later) to detect the rotation direction and the number of clicks. By detecting the rotation direction and the number of rotation clicks, it is possible to input numerical values to the camera and switch the shooting mode in combination with other operation buttons. This information setting method is known in Japanese Patent Laid-Open No. 58-63922 and Japanese Patent Laid-Open No. 60-103331, and will not be described in detail.

  Reference numeral 117 denotes a photographing mode selection switch (push button type), 118 denotes an AF mode selection switch (push button type), and 119 denotes a photometry mode selection switch (push button type), which also serves as a dimming correction switch.

  For example, when the main electronic dial 115 is rotated while pressing the shooting mode selection switch 117, the priority is changed to TV priority → AV priority → manual → program → TV priority → AV priority → manual → program. Can be set to

  When the main electronic dial 115 is rotated in the reverse direction, the shooting mode is changed as follows: program → manual → AV priority → TV priority → program →.

  When TV priority is set as a mode by the shooting mode selection switch 117 and the main electronic dial 115, the TV value desired by the photographer can be set by rotating the main electronic dial 115.

  When AV priority is set as a mode by the shooting mode selection switch 117 and the main electronic dial 115, the AV value desired by the photographer can be set by rotating the main electronic dial 115.

  Further, by simultaneously pressing the AF mode selection switch 118 and the photometry mode selection switch 119, an ISO bracketing setting mode capable of setting an ISO value and an ISO bracketing amount is selected. The ISO bracketing setting mode will be described later in detail.

  In FIG. 2, reference numeral 120 denotes an LCD monitor device (liquid crystal display) as display means for displaying a photographed image. Reference numeral 121 denotes a monitor switch for turning on / off the LCD monitor device 120.

  Since the LCD monitor device 120 according to the present embodiment is a transmissive type, an image cannot be visually recognized only by driving the LCD monitor device 120, and a backlight illumination device (not shown) is necessarily provided on the back surface.

  In FIGS. 1 and 2, reference numeral 116 denotes a sub electronic dial which is a second operation means having the same function as the main electronic dial 115. When the manual mode is set by the shooting mode selection switch 117 and the main electronic dial 115, the appropriate metering is performed in the aperture value input setting, the program mode (P), the shutter priority mode (Tv), and the aperture priority mode (Av). An exposure correction amount input setting for changing the control exposure amount of the camera is performed for the exposure.

  In FIG. 2, 122 is a dial lock switch for locking the input function by the sub electronic dial 116, and 123 is a main switch for starting / prohibiting all operations of the digital camera.

Reference numeral 124 denotes a menu button for selecting a mode when displaying an image on the LCD monitor device 120 or when initializing the camera. When selecting each mode, the sub-electronic dial 116 is pressed while pressing the menu button 124. Rotate to select the desired mode. When the desired mode is selected, release the menu button 124 to complete the selection.
Reference numeral 140 denotes an external liquid crystal display device including a liquid crystal display device having an external display function for displaying photographing conditions and the like.

  The photographing lens 200 can be exchanged with the camera body 100 via a body mount (not shown).

  FIG. 3 is a detailed view of the external liquid crystal display device 140, and shows a display state during normal shooting of the camera.

  Reference numeral 140a denotes a segment indicating the exposure mode, and FIG. 3 shows a state where the program shooting mode (P) is selected. Reference numeral 140b denotes a shutter time display segment and an aperture value display segment. FIG. 3 shows shutter time: 1/250 and aperture value: 5.6. Reference numeral 140c denotes a counter for the number of shootable images, and in FIG. 3, it indicates that the remaining 153 images can be shot. Reference numeral 140d denotes a segment indicating the exposure correction amount, and FIG. 3 illustrates a state in which exposure correction is not performed (correction 0).

  FIG. 4 is a block diagram showing a circuit configuration of a single-lens reflex type digital camera according to the present invention.

  In FIG. 4, reference numeral 1 denotes a central processing unit (hereinafter referred to as MPU) of a microcomputer which is a control means built in the camera body. The MPU 1 includes an AF drive circuit 12, an aperture drive circuit 13, a mirror drive circuit 14, a focus detection circuit 16, a shutter drive circuit 17, a video signal processing circuit 11, a switch sense circuit 21, a photometry circuit 23, and a liquid crystal display drive circuit 24. It is connected. The MPU 1 sequentially controls each element and the circuit in a predetermined order.

  The AF drive circuit 12 is configured by, for example, a stepping motor, and focuses on a solid-state image sensor (hereinafter referred to as a CCD) 7 by changing the focus lens position in the photographing lens 200 under the control of the MPU 1.

  The aperture driving circuit 13 is configured by, for example, an auto iris or the like, and changes the optical aperture value by changing the aperture 2 under the control of the MPU 1.

  A main mirror 4 guides the subject image formed by the photographing lens 200 to the pentaprism 3 and transmits a part of the image to the focus detection sensor 15 through a sub-mirror 5 described later. The mirror drive circuit 14 is configured to move the main mirror 4 to a position where the subject image can be observed with the viewfinder and a retreat position where the subject image is retracted from the optical path of the subject light beam during photographing.

  Reference numeral 5 denotes a sub-mirror for reflecting the subject light transmitted through a part of the main mirror 4 and guiding the subject image to the focus detection sensor 15. The sub mirror 5 is linked with the main mirror 4 or the mirror drive circuit 14 of the main mirror 4, and when the main mirror 4 is at a position where the subject image can be observed with the viewfinder, the sub mirror 5 is a position for guiding the subject light to the focus detection sensor 15. In addition, at the time of shooting, the subject is moved to a retreat position that is retracted from the optical path of the subject light flux.

  The mirror drive circuit 14 is composed of, for example, a DC motor and a gear train, and drives the main mirror 4 and the sub mirror 5 under the control of the MPU 1.

  Reference numeral 3 denotes a penta roof prism, which is an optical member that converts and reflects an object image guided by the main mirror 4 into an erect image.

  The subject luminous flux that has passed through the photographic lens 200 passes through the stop 2, is reflected by the main mirror 4, is guided to the pentaprism 3, and is observed as a subject image through the eyepiece window 111. Furthermore, it is guided to the photometric sensor 22. Further, the light beam that has passed through the main mirror 4 is reflected by the sub mirror 5 and re-imaged on the detection surface of the focus detection sensor 15 placed at a position substantially equivalent to the CCD 7 surface. The optical image is converted into an electrical image signal and supplied to the focus detection circuit 16.

  The focus detection circuit 16 performs accumulation control and readout control of the focus detection sensor 15 according to the signal of the MPU 1 and outputs pixel information to the MPU 1. The MPU 1 performs a focus detection calculation by a known phase difference detection method based on the image signal of the subject image from the focus detection circuit 16, and the difference between the imaging surface formed by the photographic lens 200 and a predetermined imaging surface such as a film surface, That is, the defocus amount and the defocus direction are obtained. Then, the MPU 1 changes the focus lens position in the photographing lens 200 via the AF drive circuit 12 based on the calculated defocus amount and defocus direction, and drives to the in-focus position.

  Reference numeral 6 denotes a mechanical shutter device that blocks the subject luminous flux during viewfinder observation, retracts from the optical path of the subject luminous flux according to the release signal during imaging, and starts from the unillustrated front blade group during the finder observation, and from the optical path of the subject luminous flux during finder observation. It is a focal plane shutter that is retracted and has a rear blade group (not shown) that shields the subject luminous flux at a predetermined timing after the start of traveling of the front blade group during imaging. The mechanical shutter device 6 is controlled by a shutter drive circuit 17 that receives a command from the MPU 1.

  In this embodiment, the case of having both the front blade group and the rear blade group is described, but when the exposure is started with only one shielding member, it is retracted from the optical path of the subject luminous flux, It may be configured to return to a position where the light path of the subject light flux is again blocked after the photographing is completed.

  Reference numeral 7 denotes a solid-state image sensor that captures a subject image formed by the photographing lens 200 and converts it into an electrical signal. As the solid-state imaging device, a CCD that is a known two-dimensional imaging device is used. There are various types of imaging devices such as a CCD type, a MOS type, and a CID type, and any type of imaging device may be adopted. In this embodiment, a photoelectric conversion element (photosensor) is two-dimensional. An interline type CCD is employed in which signal charges accumulated in each sensor are output via a vertical transfer path and a horizontal transfer path.

  Reference numeral 8 denotes a clamp / CDS (correlated double sampling) circuit which performs basic analog processing before A / D conversion and can also change the clamp level.

  Reference numeral 9 denotes an AGC (automatic gain adjusting device) which performs basic analog processing before A / D conversion and can change the AGC basic level. The AGC basic level is set to a value corresponding to the ISO setting described later. That is, when the ISO value is changed, the basic level of AGC is changed. The CCD 7, the clamp / CDS circuit 8, the AGC 9, and the A / D converter 10 constitute an imaging means.

  Reference numeral 11 denotes a video signal processing circuit which takes charge of overall image processing by hardware such as gamma / knee processing, filter processing, and information composition processing for monitor display on the digitized image data of the CCD 7. The image data for monitor display from the video signal processing circuit 11 is displayed on the LCD monitor 120 via the LCD drive circuit 25.

  These functions are switched by exchanging data with the MPU 1, and the white balance information of the output signal of the CCD 7 can be output to the MPU 1 as needed. Based on this information, the MPU 1 performs white balance adjustment and gain adjustment. Do.

  Further, it is also possible to store image data in the buffer memory 27 through the memory controller 26 without doing anything in response to an instruction from the MPU 1. The video signal processing circuit 11 also has a function of performing compression processing such as JPEG.

  In the case of continuous shooting, image data is temporarily stored in the buffer memory 27. When processing time is required, unprocessed image data is read through the memory controller 26, and the video signal processing circuit 11 performs image processing and compression processing. It is configured to increase the continuous shooting speed. The number of continuous shots greatly depends on the size of the buffer memory 27.

  In the memory controller 26, unprocessed digital image data input from the video signal processing circuit 11 is stored in the buffer memory 27, and the processed digital image is stored in the memory 28, or conversely from the buffer memory 27 and the memory 28. Image data is output to the video signal processing circuit 11.

  In addition, the memory controller 26 can store the video transmitted from the outside via the interface 29 in the memory 28 and can output the image stored in the memory 28 to the outside from the interface 29. The memory 28 can be removed from the camera body.

  Reference numeral 21 denotes a switch sense circuit which controls each part according to the operation state of each switch. Reference numeral 114a denotes a switch SW1 that is turned on by the first stroke of the release button 114 to start a shooting preparation operation. 114b is a switch SW2 that is turned on by the second stroke of the release button 114. When the switch SW2 is turned on, the release operation is started.

  The main electronic dial 115, the sub electronic dial 116, the shooting mode selection switch 117, the AF mode selection switch 118, and the photometry mode selection switch 119 are connected, and the state of each switch is transmitted to the MPU 1.

  A photometric circuit 23 outputs an output from the photometric sensor 22 to the MPU 1 as a luminance signal for each area in the screen. The MPU 1 performs A / D conversion on the luminance signal and calculates the exposure for photographing.

  A liquid crystal display drive circuit 24 drives the external liquid crystal display device 140 and the in-finder liquid crystal display device 30 in accordance with the display content command of the MPU 1. Further, the liquid crystal display driving circuit 24 can put a specific segment in a blinking display state according to an instruction from the MPU 1.

  A power source 31 supplies power necessary for each IC (integrated circuit) and drive system.

  Next, a setting method for ISO bracketing shooting will be described with reference to FIGS. ISO bracketing shooting is to perform shooting by changing the ISO value stepwise without changing the exposure time (without changing the shutter speed or aperture value).

  In this embodiment, the ISO value is changed by changing the gain of the CCD 7. However, the present invention is not limited to this. For example, the gamma value may be changed.

  In step S100 of FIG. 6, it is determined whether both the AF mode selection switch 118 and the photometry (AE) mode selection switch 119 are turned on. If it is determined that it is turned on, the process proceeds to step S101 to enter the ISO bracketing setting mode. At this time, the external liquid crystal display device 140 displays as shown in FIG.

  In FIG. 5, (a) shows an initial state. When an operation described in detail later is performed, the display changes to the display after (b). Reference numeral 140c denotes a set ISO value. Reference numeral 140d denotes the ISO bracketing correction amount in dots, and one dot represents 1/3 level. Reference numeral 140b indicates a bracketing correction amount in a 7-segment display.

  Returning to FIG. 6, in steps S102 and S104, the input of the main electronic dial 115 and the sub electronic dial 116 is discriminated, respectively. When no input is made, the process proceeds to step S107.

  When the input of the main electronic dial 115 is confirmed in step S102, the ISO value is changed in step S103. In this case, if the initial value is ISO200, the display of 140c in FIG. 5 is performed in 1/3 steps from 200 to 250 to 320 to 400 to 1600 every time the main electronic dial 115 is rotated by one click. It will increase. Further, when operated in the reverse rotation direction, 1600 → 1250 → 1000 → 800.

  Returning to FIG. 6, when the input of the sub electronic dial 116 is confirmed in step S104, the bracketing correction amount is determined in step S105. At this time, the display of 140d in FIG. 5 changes from the initial state of FIG. 5A by one dot every time the sub electronic dial 116 is rotated by one click. FIG. 5B shows a dot state when the sub electronic dial 116 is operated by one click from the initial state FIG. 5A, and FIG. 5C shows two clicks from the initial state of the sub electronic dial 116. Indicates the operated state. Further, when the sub electronic dial 116 is rotated in the reverse direction, the state changes from the state of FIG. 5C to the state of FIG. 5B to FIG.

  The display of 140b also corresponds to the display of dots, and every time the sub electronic dial 116 is rotated by one click, it is incremented by 1/3 from 0.0 → 0.3 → 0.7 →. It will change. Further, when rotated in the reverse direction, it changes from 3.0 → 2.7 → 2.3 →.

  Returning to FIG. 6, when the ISO bracketing correction is performed in step S105, an ISO bracketing flag is set in step S106, the variable N = 0 is stored in the memory in the MPU 1, and step S107 is performed. Migrate to When this flag is set, ISO bracketing shooting described later is performed. In other words, when the sub electronic dial 116 is operated in the ISO bracketing setting mode and the bracketing correction amount is set, ISO bracketing shooting is performed.

  In step S107, it is determined whether or not the AF mode selection switch 118 and the photometry (AE) mode selection switch 119 are turned off. If they are not turned off, the operations described above are repeated, and when it is determined that they are turned off. The process proceeds to step S108.

  In step S108, it is determined whether or not an ISO bracketing flag (variable N = 0) is set. When it is set, the process proceeds to step S109, and when it is not set, the ISO bracketing setting mode is ended.

  In step S109, the MPU 1 serving as the control unit changes the display of the segment 140c of the external liquid crystal display device 140 described with reference to FIG. 3 to ISO display. The display at this time is the display of FIG.

  Here, the display during ISO bracketing shooting will be described with reference to FIG. FIGS. 9A, 9B, and 9C show display states at the time of photographing under-exposure, proper exposure, and over-exposure, respectively. In FIG. 9A, 140c indicates the ISO value at the time of ISO bracketing shooting (in normal shooting, it is the value of the counter for the number of shots that can be taken as described in FIG. 3). Reference numeral 140d represents an exposure correction amount at the time of ISO bracketing shooting, and represents that -1/3 step correction is performed. The 140d dot continues to blink during ISO bracketing shooting. An ISO display segment 140e informs the photographer that the display 140c is an ISO display. Further, since blinking continues during ISO bracketing shooting, the photographer can know that the camera is not in ISO setting mode but ISO bracketing shooting. The display of FIGS. 9B and 9C will be described later.

  As described above, when ISO bracketing shooting is performed, the photographer always confirms the ISO value during ISO bracketing shooting by switching the segment in which the number of possible shots is displayed to ISO display during normal shooting. It becomes possible to do.

  In addition, since the segment is shared, it is not necessary to add a new display device or segment, so that an increase in cost and an increase in size of the camera can be prevented.

  Next, an ISO bracketing shooting sequence will be described with reference to FIG. In step S201 in FIG. 7, it is determined whether or not the switch SW1 is turned on. If it is determined that the switch SW1 is turned on, the process proceeds to step S202.

  In step S202, based on the data output from the photometry circuit 23, the MPU 1 calculates an exposure value (calculates shutter speed and aperture value). The photometric circuit 23 performs a known photometric calculation weighted to a photometric area (not shown) including the focused focus detection area, and an exposure value is calculated. At the same time, the MPU 1 calculates and determines the lens driving amount based on the focus information that is the output of the focus detection circuit 16, drives a part of the photographing lens 200 using the AF driving circuit 12, and adjusts the focus.

  In step S203, it is determined whether or not the switch SW2 is turned on. When it is determined that it is not turned on, the process proceeds to step S201, and the operation already described is repeated. If it is determined in step S203 that the power has been turned on, the process proceeds to step S204.

  The photographing process in step S204 will be described in detail with reference to FIG.

  FIG. 8 shows a detailed flowchart of the photographing process in step S204 of FIG.

  In step S301, the mirror drive circuit 14 moves the main mirror 4 and the sub mirror 5 to the mirror-up position according to a command from the MPU 1.

  In step S302, the MPU 1 drives the aperture 2 by the aperture drive circuit 13 to the aperture value calculated in step S202 of FIG.

  In step S303, after performing the charge clear operation of the CCD 7, the MPU 1 starts charge accumulation in the CCD 7 in step S304, and proceeds to step S305.

  In step S305, the shutter drive circuit 17 drives the leading blade group in the mechanical shutter device 6 (the shutter is opened), and exposure of the CCD 7 is started (step S306).

  In step S307, the MPU 1 determines whether or not the exposure time of the CCD 7 calculated in step S202 of FIG. 7 has ended. If it is determined that the exposure time has ended, the process proceeds to step S308.

  In step S308, the shutter drive circuit 17 drives the rear blade group in the mechanical shutter device 6 according to the instruction of the MPU 1, closes the shutter, and ends the exposure of the CCD 7.

  In step S309, the aperture driving circuit 13 drives the aperture 2 to the full aperture value, and the main mirror 4 and the sub mirror 5 are moved to the mirror down position by the mirror driving circuit 14 in step S310.

  In step S311, it is determined whether or not the set charge accumulation time has elapsed. If it is determined that it has elapsed, the process proceeds to step S312.

  In step S312, the MPU 1 ends the charge accumulation of the CCD 7, and then reads out a charge signal from the CCD 7 in step S313.

   When the series of processing is finished, the photographing processing routine step S204 is finished, and the process proceeds to step S205.

  In step S205, it is determined whether or not the ISO bracketing flag is set in step S106 of FIG. When the ISO bracketing flag is not set, the process proceeds to step S211 and an operation described later is performed.

  When the ISO bracketing flag is set, the process proceeds to step S206. In step S206, the MPU 1 checks the value of the variable N. If N = 0, the process proceeds to step S207, and the AGC 9 underestimates the gain corresponding to the bracketing correction amount set in step S106 in FIG. Correct to the side. Thereafter, the process proceeds to step S210.

  If N = 1, the process proceeds to step S208, and the AGC 9 performs gain correction corresponding to the ISO value set in step S103 in FIG. 6, and then proceeds to step S210.

  If N = 2, the process proceeds to step S209, and the AGC 9 corrects the gain to the over side by an amount corresponding to the bracketing correction amount set in step S106 in FIG. 6, and the process proceeds to step S211.

  In step S210, the display on the external liquid crystal display device 140 is switched. Display switching will be described in detail with reference to FIG. FIG. 9A shows that under-exposure occurs immediately after ISO bracketing is set, as already described. FIG. 9A shows a state in which −1/3 step correction is performed.

  FIG. 9B shows a photographing state with appropriate exposure in a state where the display is switched in step S210 after the setting in step S207 in FIG. 140c indicates the ISO value set in step S102 of FIG. 6, and 140d indicates a state of zero correction.

  FIG. 9C shows an over-exposure shooting state in which the display is switched in step 210 after the setting in step S208 in FIG. FIG. 9C shows a state where +1/3 stage correction is performed. Reference numeral 140c denotes an ISO value corresponding to the bracketing correction amount set in step S105 of FIG.

  In this way, since the ISO value during ISO bracketing is always displayed, the photographer can take an image while always being aware of noise increase / decrease due to a change in ISO.

  Returning to FIG. 7, after predetermined image processing is performed in the video signal processing circuit 11 in step S <b> 211, compression processing is performed, the process proceeds to step S <b> 212, and the memory controller 26 records the compressed data in the memory 28. Then, the process proceeds to step S213.

  In step S213, the MPU 1 checks the state of the ISO bracketing flag stored in the internal memory in the MPU 1. If the ISO bracketing flag is set, the process proceeds to step S214, and the ISO bracketing flag has been released. Then, the series of shooting is finished.

  In step S214, MPU1 sets N = N + 1 for variable N, and proceeds to step S215.

  In step S215, the MPU 1 determines whether or not the variable N has reached N = 3. If it is determined that the variable N has reached N = 3, the ISO bracketing flag is canceled in step S216, and the shooting is performed. Exit.

  If it is determined in step S214 that the variable N has not reached N = 3, the process returns to step S204 to perform the next shooting.

  Although the present embodiment has been described with ISO bracketing, the present invention is not limited to this, and can be applied to, for example, white balance bracketing. In this case, the color temperature is set with the main electronic dial, and the color temperature is corrected by the correction amount set with the sub electronic dial. During white balance bracketing shooting, the white balance adjustment value, for example, the color temperature is displayed on the segment 140c in the external liquid crystal display device 140.

1 is a top view illustrating an appearance of a digital single-lens reflex camera that is an embodiment of the present invention. FIG. 1 is a rear view showing an appearance of a digital single-lens reflex camera that is an embodiment of the present invention. FIG. It is a figure which shows the example of a normal display of the external liquid crystal display device of the digital single-lens reflex camera which is an Example of this invention. It is a block diagram which shows the electric circuit structure of the digital single-lens reflex camera which is an Example of this invention. It is a figure which shows the example of a display of an external liquid crystal display device at the time of ISO bracketing setting of the digital single-lens reflex camera which is an Example of this invention. It is a flowchart which shows the ISO bracketing setting operation | movement of the digital single-lens reflex camera which is an Example of this invention. 4 is a flowchart showing an ISO bracketing shooting operation of the digital single-lens reflex camera according to the embodiment of the present invention. It is a flowchart which shows the imaging | photography subroutine of the digital single-lens reflex camera which is an Example of this invention. It is a figure which shows the example of a display of an external liquid crystal display device in ISO bracketing imaging | photography of the digital single-lens reflex camera which is an Example of this invention.

Explanation of symbols

1 Microcomputer (MPU)
2 Aperture 3 Penta roof prism 4 Main mirror 5 Sub mirror 6 Mechanical shutter device 7 CCD (solid-state imaging device)
8 Clamp / CDS circuit 9 AGC
10 A / D converter 24 Liquid crystal display drive circuit 100 Camera body 114 Release button 115 Main electronic dial 116 Sub electronic dial 117 Shooting mode selection switch 118 AF mode selection switch 119 Metering mode selection switch 120 LCD monitor 140 External liquid crystal display device 200 Shooting lens

Claims (5)

In an electronic camera equipped with an imaging means for capturing an image of a subject and an auto bracketing shooting mode for automatically performing shooting with ISO sensitivity changed a plurality of times,
Display means for displaying information relating to shooting, setting means for setting the auto bracketing shooting mode, and when the auto bracketing shooting mode is set by the setting means, the ISO speed is displayed on the display means during auto bracketing shooting. An electronic camera having an auto bracketing function, comprising: control means for controlling to display the value of.   When the auto bracketing shooting mode is set by the setting means, the control means controls to change a part of the information related to the normal shooting displayed on the display means to the ISO sensitivity value during the auto bracketing shooting. An electronic camera having an auto bracketing function according to claim 1. In an electronic camera equipped with an image pickup means for picking up an image of a subject and an auto bracketing shooting mode in which shooting with changed adjustment values for automatically performing white balance adjustment is performed a plurality of times.
Display means for displaying information relating to shooting, setting means capable of setting the auto bracketing shooting mode, and when the auto bracketing shooting mode is set by the setting means, white light is displayed on the display means during auto bracketing shooting. An electronic camera having an auto bracketing function, comprising control means for controlling to display an adjustment value for balance adjustment.   When the auto bracketing shooting mode is set by the setting means, the control means adjusts part of the information related to normal shooting displayed on the display means for white balance adjustment during auto bracketing shooting. 4. The electronic camera having an auto bracketing function according to claim 3, wherein the electronic camera is controlled to change to a value. 5. The electronic camera having an auto bracketing function according to claim 3, wherein the adjustment value for white balance adjustment displayed on the display means is a color temperature value.

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