JP4780877B2 - Electronic camera and control method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention , Electric Regarding child camera.
[0002]
[Prior art]
Conventionally, with still cameras using silver halide film, if it is difficult to determine the proper exposure, such as when there are some scenes at sunset or subjects with high reflectivity, multiple exposures can be made while slightly changing the exposure of the same scene. A so-called Automatic Exposure Bracketing is performed in which a frame is taken and an appropriate exposure frame is selected from the frames.
[0003]
Even when an electronic camera using a CCD or the like is used as an imaging device, the circumstances relating to exposure are the same. When shooting with an inappropriate exposure amount, a dark image (underexposure) or conversely too bright (overexposure) Therefore, in scenes where it is difficult to determine exposure, auto bracket shooting is performed in the same manner as a silver halide film camera.
[0004]
As a setting method of such an auto bracket shooting mode, conventionally, an auto bracket setting mode is selected, and an operation member such as an electronic dial is operated to set a correction amount for performing bracket shooting. Then, returning to the normal shooting mode, the exposure value for shooting is determined. Then, with respect to this exposure value, the set correction amount and exposure are changed (shutter speed and aperture value are changed), and photographing is automatically performed.
[0005]
That is, the center value (reference value) for performing auto bracket shooting is determined when the auto bracket setting mode is canceled and the exposure value is determined in the normal shooting mode.
[0006]
Further, as a technique peculiar to an electronic camera, there is a technique in which auto bracket shooting is performed by automatically changing the ISO sensitivity value by changing CCD gain (imaging sensitivity of an imaging device) and gamma characteristics. This is disclosed in Japanese Patent No. 004380.
[0007]
In addition, an apparatus is disclosed that can select a resolution of a set value such as an aperture value or a shutter speed from among candidates prepared in advance in order to expand a shooting expression area.
[0008]
Also in an electronic camera using an electronic device such as a CCD, it is common to use the film sensitivity (ISO sensitivity) of a silver salt film camera as a set value for the gain of the imaging device which is the electronic device, that is, the photographing sensitivity. .
[0009]
This is because users are often users of not only electronic cameras but also silver halide film cameras, and the methods and devices used in silver halide film cameras are used as they are when determining shooting parameters (aperture and shutter speed). Because it can.
[0010]
The sensitivity setting of commercially available film (ISO sensitivity) is 1/3 step. Therefore, the photographing sensitivity (ISO sensitivity) resolution that can be set for both the silver salt film camera and the electronic camera is usually 1/3 step.
[0011]
[Problems to be solved by the invention]
This imaging sensitivity (ISO sensitivity) resolution is fixed to a 1/3 step step even in a silver halide film camera and an electronic camera that can change various imaging parameter resolutions. The reason is that the sensitivity of the silver salt film is set in 1/3 step, and the user of the electronic camera often overlaps with the user of the silver salt film camera. Therefore, if the standard ISO sensitivity setting value can be set with a resolution other than 1/3 step that is different from that of conventional films, the ISO sensitivity that is not found in silver halide film can be selected, which can confuse the user. It is possible to invite.
[0012]
Also, in the electronic camera, when considering the ISO bracket shooting mode in which the shooting sensitivity of the imaging device is shaken, if the bracket correction amount can be set only at 1/3 step which is the set value resolution of the ISO sensitivity (shooting sensitivity), It is conceivable that an appropriate exposure cannot be obtained or an image required by the user cannot be obtained. In other words, it is possible to hinder the user's freedom of shooting expression.
[0013]
The present invention has been made in view of the above circumstances. , Shooting It is an object of the present invention to provide an electronic camera and a control method that are configured so as not to cause user confusion while increasing the degree of freedom of shadow expression.
[0014]
[Means for Solving the Problems]
The solution means in the present invention is summarized as follows.
[0015]
That is, An electronic camera according to the present invention is an electronic camera capable of changing a setting value of a parameter relating to exposure, wherein the changing means changes a step width when changing the setting value of the parameter relating to exposure, A control means for reflecting the change of the step width when changing the setting values of a plurality of parameters other than the shooting sensitivity among the parameters relating to the exposure, and not reflecting when changing the setting value of the shooting sensitivity, It is characterized by having.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of an electronic camera according to the present invention will be described below.
[0017]
FIG. 1 is a top view of the appearance of a single-lens reflex type electronic camera according to an embodiment of the present invention, FIG. 2 is a rear view of the appearance of a single-lens reflex type electronic camera according to an embodiment of the present invention, and FIG. 4 is a block diagram showing the configuration of a control system of a single-lens reflex type electronic camera in the embodiment, and FIGS. 4 (a), (b), (c), (b ′), (c ′), and (d ′) are the present invention. FIG. 5 is an explanatory diagram showing a display example of the LCD monitor device of the single-lens reflex type electronic camera in the embodiment according to FIG. 5, FIG. 5 is a flowchart showing the ISO bracket setting operation of the single-lens reflex type electronic camera in the embodiment according to the present invention, and FIG. FIG. 7 is a flowchart showing a photographing sequence of an ISO bracket of a single-lens reflex type electronic camera according to an embodiment of the present invention. FIG. 7 is a flowchart showing details of photographing processing in step S204 of FIG. It is over door.
[0018]
Hereinafter, embodiments of the present invention will be described in detail with reference to examples of single-lens reflex type electronic cameras.
[0019]
In the present 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.
[0020]
1 and 2 show a “single-lens reflex type electronic camera” which is an embodiment of the present invention.
[0021]
FIG. 1 is an external top view showing the configuration of a single-lens reflex electronic camera according to an embodiment of the present invention, and FIG. 2 is an external rear view showing the configuration of the electronic camera.
[0022]
In each figure, 100 is a camera body, and 111 is an eyepiece window for viewfinder observation. 1 and 2, reference numeral 112 denotes an AE (automatic exposure) lock button, and 113 denotes an AF (autofocus) distance measuring point selection button.
[0023]
Reference numeral 114 denotes a release button for performing a photographing operation, which is configured such that SW1 is turned on in the first stroke and SW2 is turned on in the second stroke.
[0024]
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 the microcomputer 1 to detect the rotation direction and the number of clicks.
[0025]
By detecting this 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.
[0026]
Since this information setting method is known in Japanese Patent Laid-Open Nos. 58-63922 and 60-103331, detailed description thereof is omitted.
[0027]
In FIGS. 1 and 2, 117 is a shooting mode selection button, 118 is an AF mode selection button, 119 is a photometry mode selection button, and also functions as a light control button.
[0028]
For example, when the main electronic dial 115 is rotated while the shooting mode selection button 117 is pressed, Tv priority → Av priority → manual → program → Tv priority → Av priority → manual → program is changed to a mode intended by the photographer. Can be set.
[0029]
Further, when the main electronic dial 115 is rotated in the reverse direction, the mode is changed from program → manual → Av priority → Tv priority → program →.
[0030]
When Tv priority is set as a mode by the shooting mode selection button 117 and the electronic dial 115, the Tv value desired by the photographer can be set by rotating the main electronic dial 115. At this time, the amount of change per one click of the dial rotation can be changed by selecting and setting a dial resolution setting SW described later.
[0031]
When Av priority is set as a mode by the shooting mode selection button 117 and the main electronic dial 115, the Av value desired by the photographer can be set by rotating the main electronic dial 115. At this time, the amount of change per one click of the dial rotation can be changed by selecting and setting a dial resolution setting SW described later.
[0032]
Further, by simultaneously pressing the AF mode selection button 118 and the photometry mode selection button 119, an ISO bracket setting mode capable of setting an ISO value and setting an ISO bracket is selected. The ISO bracket setting mode will be described later in detail.
[0033]
2 and 3, reference numeral 120 denotes an LCD monitor device (liquid crystal display) as display means for displaying a photographed image.
[0034]
In FIG. 2, reference numeral 121 denotes a monitor switch for turning on / off the LCD monitor device 120.
[0035]
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, and a backlight illumination device (not shown) is always required on the back surface.
[0036]
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 button 117 and the main electronic dial 115, the appropriate exposure measured in the aperture value input setting, program mode (P), shutter priority mode (Tv), and aperture priority mode (Av). On the other hand, the exposure correction amount input setting for changing the control exposure amount of the camera is performed.
[0037]
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 prohibiting all operations of the electronic camera.
[0038]
125 designates the amount of change per dial when the main electronic dial 115 and sub electronic dial 116 are used to set the shutter speed, aperture value, exposure correction amount, bracket correction amount, etc., that is, dial resolution. Dial resolution setting SW (setting value resolution changing means). When in the position shown in FIG. 2, the dial resolution is set to “1/2 stage”. When SW is set on the left side, “1/3 stage” is set.
[0039]
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, the selection / setting is completed when the menu button 124 is released.
[0040]
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.
[0041]
The photographing lens 200 can be exchanged with the camera body 100 via a body mount (not shown).
[0042]
FIG. 3 is a block diagram showing the configuration of the control system of the “single-lens reflex electronic camera” that is an embodiment of the present invention.
[0043]
In FIG. 3, 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.
[0044]
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 photometric 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.
[0045]
Reference numeral 200 denotes a photographing lens, and reference numeral 12 denotes an AF (autofocus) driving circuit, which is configured by, for example, a stepping motor, and focuses on the CCD 7 by changing the focus lens position in the photographing lens 200 under the control of the MPU 1.
[0046]
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.
[0047]
The main mirror 4 guides the subject image formed by the photographing lens 200 to the pentaprism (pentagonal roof prism) 3 and transmits part of the subject image to the focus detection sensor 15 through the submirror 5 described later. It is. The mirror drive circuit 14 is configured to be movable between a position where the subject image can be observed by the finder and a retreat position where the subject image is retracted from the optical path of the subject light beam during photographing.
[0048]
Reference numeral 5 denotes a sub-mirror for reflecting 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 to the main mirror 4 or the mirror driving circuit 14 of the main mirror 4, and when the main mirror 4 is at a position where a subject image can be observed with a finder, the sub mirror 5 is connected to the focus detection sensor 15. It is configured to be movable to a position for guiding light and to a retreat position for retreating from the optical path of the subject light beam at the time of photographing.
[0049]
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.
[0050]
The pentaprism (pentagonal roof prism) 3 is an optical member that converts and reflects the subject image guided by the main mirror 4 into an erect image.
[0051]
The subject luminous flux that has passed through the photographing lens 200 passes through the aperture 2, is reflected by the main mirror 4, is guided to the pentaprism 3, and the subject image is observed through the eyepiece window 111.
[0052]
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.
[0053]
The optical image is converted into an electrical image signal and supplied to the focus detection circuit 16.
[0054]
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.
[0055]
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.
[0056]
Then, based on the calculated defocus amount and defocus direction, the MPU 1 changes the focus lens position in the photographing lens 200 via the AF drive circuit 12 and drives it to the in-focus position.
[0057]
Reference numeral 6 denotes a mechanical shutter device that blocks the subject luminous flux during finder observation, and retracts from the optical path of the subject luminous flux according to a release signal during imaging, and a leading blade group 6a (not shown) that starts exposure, and the subject luminous flux during finder observation. It is a focal plane shutter that is retracted from the optical path and has a rear blade group 6b (not shown) that shields the subject luminous flux at a predetermined timing after the start of traveling of the front blade group 6a during imaging. The mechanical shutter device 6 is controlled by a shutter drive circuit 17 that receives a command from the MPU 1.
[0058]
In the present embodiment, the case where both the front blade group 6a and the rear blade group 6b are provided is described. However, when exposure is started with only one shielding member, the light beam is retracted from the optical path of the subject luminous flux. However, it may be configured to return to a position where the optical path of the subject light flux is again blocked after the photographing is completed.
[0059]
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. A CCD, which is a known two-dimensional imaging device, is used as the solid-state imaging device. There are various types of imaging devices such as a CCD type, a MOS type, a CID type, and a CPD type, and any type of imaging device may be adopted. In this embodiment, a photoelectric conversion element (photosensor) ) Are two-dimensionally arranged, and an interline CCD image pickup device is employed in which signal charges accumulated in each sensor are output via a vertical transfer path and a horizontal transfer path.
[0060]
Reference numeral 8 denotes a clamp / CDS (correlated double sampling) circuit that performs basic analog processing before A / D conversion and can also change the clamp level.
[0061]
Reference numeral 9 denotes an AGC (automatic gain adjusting device) that 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.
[0062]
An A / D converter 10 converts an analog CCD 7 output signal into a digital signal.
[0063]
The CCD 7, the clamp / CDS circuit 8, the AGC 9, the A / D converter 10, and a CCD drive circuit (not shown) constitute an imaging means.
[0064]
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.
[0065]
The image data for monitor display from the video signal processing circuit 11 is displayed on the LCD monitor device 120 via the LCD drive circuit 25.
[0066]
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.
[0067]
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.
[0068]
Further, 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 image processing and compression processing are performed by the video signal processing circuit 11. It is configured to increase the continuous shooting speed.
[0069]
The number of continuous shots greatly depends on the capacity of the buffer memory 27.
[0070]
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.
[0071]
Further, the memory controller 26 can store the video sent from the external interface 29 in the memory 28 and can output the image stored in the memory 28 from the external interface 29. The memory 28 is configured to be detachable from the camera body.
[0072]
Reference numeral 21 denotes a switch sense circuit which controls each part according to the operation state of each switch.
[0073]
Reference numeral 114a denotes a switch SW1 that is turned on by the first stroke of the release button 114. 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.
[0074]
The main electronic dial 115, sub electronic dial 116, shooting mode selection button 117, AF mode selection button 118, photometry mode selection button 119, and dial resolution setting SW 125 are connected, and the state of each button / SW is transmitted to the MPU 1. To do.
[0075]
When the dial resolution setting SW 125 is set to the “1/2” side (the state shown in FIG. 2), the amount of change per click when the main electronic dial 115 and the sub electronic dial 116 are rotated is set to 1 / Set to 2 levels. When it is set to the “1/3” side, the amount of change per click when the main electronic dial 115 and the sub electronic dial 116 are rotated is set to 1/3 step. The parameters whose resolution is changed are shutter speed, aperture value, exposure correction amount, and bracket correction amount.
[0076]
The ISO sensitivity setting value, that is, the reference value in the ISO bracket shooting mode, is displayed as “1” regardless of the position of the dial resolution setting SW 125 so that the ISO sensitivity that does not exist in the silver halide film is displayed, so as not to confuse the user. / 3 stage "step.
[0077]
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 at the time of shooting.
[0078]
A liquid crystal display driving circuit 24 drives the external liquid crystal display device 140 and the in-finder liquid crystal display 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.
[0079]
A power source 31 supplies power necessary for each IC (integrated circuit) and drive system.
[0080]
Next, an ISO bracket shooting setting method will be described with reference to FIGS.
[0081]
ISO bracket photography means changing the shooting sensitivity value of the image sensor (the gain adjustment value of the image signal output from the image sensor) without changing the exposure time (without changing the shutter speed or aperture value). It is to shoot.
[0082]
In the present embodiment, the gain adjustment value will be described for the sake of simplification, but of course, the object of the present invention can be achieved even when the exposure of the image such as the shutter speed and the aperture value is controlled. Can do.
[0083]
In step S100 in FIG. 5, it is determined whether both the AF mode selection button (SW) 118 and the AE mode selection button (SW) 119 are turned on. If it is determined that it has been turned ON, the process proceeds to step S101 to enter the ISO bracket setting mode. At this time, the external liquid crystal display device 140 displays as shown in FIGS. 4 (a), (b), (c), (b ′), (c ′), and (d ′).
[0084]
FIG. 4 shows the display screen of the external liquid crystal display device 140, and the dot display shown below the display screen indicates that bracket shooting is performed with the bracket correction amount (gain adjustment amount). That is, this embodiment shows that gain adjustment is performed with three different bracket correction amounts (gain adjustment amounts).
[0085]
In FIG. 4, FIG. 4 (a) shows an initial state. When an operation that will be described in detail later is performed, the display changes to the display after FIG. 4B or FIG. 4B ′.
[0086]
Reference numeral 140a denotes a set ISO value, that is, a reference value in the ISO bracket shooting mode. Reference numeral 140b denotes an ISO bracket correction amount (gain adjustment amount) with dots, which represents 1/3 stage of one dot. When the dial resolution setting SW 125 is set to the 1/3 side, it changes in units of one dot. When the dial resolution setting SW 125 is set to the 1/2 side, the bracket correction amount (gain adjustment amount) changes in half steps. When the position of the 1/2 step is represented by dots, This is done by displaying two dots on both sides of the setting value of 1/2 level. When the position of each stage (± 1, ± 2, ± 3, etc.) is indicated by a dot, it is indicated by one dot at the corresponding position. Reference numeral 140c indicates a bracket correction amount (gain adjustment amount) in a 7-segment display.
[0087]
Returning to FIG. 5, in steps S102 and S104, the input of the main electronic dial 115 and the sub electronic dial 116 is determined. When no input is made, the process proceeds to step S109.
[0088]
When the input of the main electronic dial 115 is confirmed in step S102, the ISO value is changed in step S103.
[0089]
In this case, if the initial value is ISO 200, the display of 140a in FIG. 4 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. The gain adjustment value of the image signal increases. Further, when operated in the reverse rotation direction, the gain adjustment value of the image signal is decreased by 1/3 as 1600 → 1250 → 1000 → 800. This changes every 1/3 regardless of the position of the dial resolution setting SW125.
[0090]
Returning to FIG. 5, when the input of the sub electronic dial 116 is confirmed in step S104, the position of the dial resolution setting SW 125 is confirmed in step S105, and the dial resolution setting SW 125 is set to the 1/3 step side. If so, in step S107, the amount of change in gain adjustment per click is set to 1/3 EV, and the correction amount is determined.
[0091]
The display 140b in FIG. 4 at this time changes from the initial state of FIG. 4A by one dot every time the sub electronic dial 116 is rotated by one click. FIG. 4B shows a dot state when the sub electronic dial 116 is operated by one click from the initial state FIG. 4A, and FIG. 4C shows two clicks from the initial state of the sub electronic dial 116. Indicates the operated state.
[0092]
When the sub electronic dial 116 is rotated in the reverse direction, the state changes from the state shown in FIG. 4C to the state shown in FIG. 4B to FIG.
[0093]
The display of 140c 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. Moreover, if it rotates in the reverse direction, it will change with 3.0->2.7->2.3->...-> 0.0.
[0094]
In step S105, the position of the dial resolution setting SW 125 is confirmed. If the dial resolution setting SW 125 is set to the 1/2 stage, the amount of change in gain adjustment per click is set to 1/2 EV in step S106. Determine the correction amount.
[0095]
The display 140b in FIG. 4 at this time changes from the initial state of FIG. 4A by one dot every time the sub electronic dial 116 is rotated by one click. FIG. 4B ′ shows a dot state when the sub electronic dial 116 is operated by one click from the initial state FIG. 4A, and FIG. 4C ′ shows the sub electronic dial 116 from the initial state. 2 shows a state in which a two-click operation has been performed. FIG. 4D 'shows a state in which the sub electronic dial 116 has been operated by three clicks from the initial state.
[0096]
When the sub electronic dial 116 is rotated in the reverse direction, the state shown in FIG. 4 (d ′) is reversed one dot at a time from the state shown in FIG. 4 (c ′) to the state shown in FIG. 4 (b ′) → FIG. It will change.
[0097]
The display of 140c also corresponds to the display of dots, and every time the sub-electronic dial 116 is rotated by one click, a half step from 0.0 → 0.5 → 1.0 →. It will change. Moreover, if it rotates in the reverse direction, it will change with 3.0->2.5->2.0->...-> 0.0.
[0098]
Returning to FIG. 5, when the ISO bracket is corrected in step S106, the ISO bracket flag is set in step S108, the variable N = 0 is stored in the memory in the MPU 1, and the process proceeds to step S109. To do. When this flag is set, ISO bracket shooting described later is performed. That is, when the sub electronic dial 116 is operated in the ISO setting mode and the bracket correction amount is set, ISO bracket photographing is performed.
[0099]
In step S109, it is determined whether or not the AF mode selection button (SW) 118 / AE mode selection button (SW) 119 is turned off. If not, the operation described above is repeated to determine that the AF mode selection button (SW) 118 / AE mode selection button (SW) 119 is turned off. When done, the ISO bracket setting mode is terminated.
[0100]
Next, the ISO bracket shooting sequence will be described with reference to FIG.
[0101]
Figure 6 In step S201, it is determined whether or not SW1 (114a) is turned on. If it is determined that SW1 (114a) is turned on, the process proceeds to step S202.
[0102]
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).
[0103]
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.
[0104]
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.
[0105]
In step S203, it is determined whether or not SW2 (114b) is turned on. When it is determined that it is not ON, the process returns 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.
[0106]
The photographing process in step S204 will be described in detail with reference to FIG.
[0107]
FIG. 7 shows a detailed flowchart of the photographing process in step S204 of FIG.
[0108]
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.
[0109]
In step S302, the MPU 1 drives the diaphragm 2 by the diaphragm driving circuit 13 in accordance with the diaphragm value calculated in step S202 of FIG.
[0110]
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.
[0111]
In step S305, the shutter drive circuit 17 drives the leading blade group 6a (not shown) in the mechanical shutter device 6 (the shutter is opened), and exposure of the CCD 7 is started (step S306).
[0112]
In step S307, the MPU 1 determines whether or not the exposure time of the CCD 7 calculated in step S202 of FIG. 6 has ended. If it is determined that the exposure has ended, the process proceeds to step S308.
[0113]
In step S308, the shutter drive circuit 17 drives the rear blade group 6b (not shown) 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.
[0114]
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 13 in step S310.
[0115]
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.
[0116]
In step S312, the MPU 1 ends the charge accumulation of the CCD 7, and then reads out a charge signal as an imaging signal from the CCD 7 in step S313.
[0117]
When the series of processing is finished, the photographing processing routine step S204 is finished, and the process proceeds to step S205.
[0118]
Returning to FIG. 6, in step S205, it is determined whether or not the ISO bracket flag is set in step S108 of FIG. When the ISO bracket flag is not set, the process proceeds to step S208 and an operation described later is performed.
[0119]
When the ISO bracket flag is set, the process proceeds to step S206.
[0120]
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 bracket correction amount set in step S106 in FIG. Correct to the side (ISO under setting).
[0121]
If N = 1, the process proceeds to step S208, and the AGC 9 performs correction with a gain corresponding to the ISO value set in step S103 of FIG. 5 (ISO standard setting).
[0122]
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 bracket correction amount set in step S106 in FIG. 5 (ISO over setting).
[0123]
In step S210, after predetermined image processing is performed in the video signal processing circuit 11, compression processing is performed, and the process proceeds to step S211. The memory controller 26 records the compressed data in the memory 28, and then proceeds to step S212. Transition.
[0124]
In step S212, the MPU 1 checks the state of the ISO bracket flag stored in the internal memory in the MPU 1. If the ISO bracket flag is set, the process proceeds to step S213, and if the ISO bracket flag is cleared, Shooting ends.
[0125]
In step S213, the MPU 1 sets N = N + 1 for the variable N, and proceeds to step S214.
[0126]
In step S214, the MPU 1 determines whether the variable N has reached N = 3. If it is determined that N = 3 has been reached, the MPU 1 cancels the ISO bracket execution flag in step S215, Stop shooting.
[0127]
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.
[0128]
As a storage medium for storing a program for realizing the control method of the electronic camera in this embodiment, for example, a magnetic disk such as FD, HD, CD-ROM, CD-R, optical disk, magneto-optical disk (MO Or a non-volatile storage device such as a magnetic tape. However, the type of storage medium is not limited.
[0129]
【The invention's effect】
As explained above, according to the present invention, Increase the degree of freedom of shooting expression while avoiding user confusion Can do.
[0131]
In this embodiment, the setting value by the dial resolution setting SW, which is the setting value resolution changing means, is set to 1/2 or 1/3. The same effect can be obtained even if a resolution other than that used in the embodiment is used.
[0132]
In the present embodiment, the ISO bracket shooting mode is realized by performing shooting a plurality of times. However, it can be obtained from a single shooting result by taking advantage of the characteristics of an electronic camera that converts an image into data using an image sensor. By performing data processing on the image data, it is easy to realize an ISO bracket shooting mode that can obtain the same effect as a plurality of shootings.
[Brief description of the drawings]
FIG. 1 is an external top view of a single-lens reflex electronic camera according to an embodiment of the present invention.
FIG. 2 is an external rear view of a single-lens reflex electronic camera according to an embodiment of the present invention.
FIG. 3 is a block diagram showing a configuration of a control system of a single-lens reflex electronic camera in an embodiment according to the present invention.
4 (a), (b), (c), (b ′), (c ′), (d ′) Display examples of the LCD monitor device of the single-lens reflex type electronic camera in the embodiment according to the present invention. Illustration showing
FIG. 5 is a flowchart showing an ISO bracket setting operation of the single-lens reflex type electronic camera in the embodiment according to the invention.
FIG. 6 is a flowchart showing a shooting sequence of the ISO bracket of the single-lens reflex type electronic camera in the embodiment according to the present invention.
FIG. 7 is a flowchart showing details of photographing processing in step S204 of FIG.
[Explanation of symbols]
1 Microcomputer (MPU)
2 Aperture
3 Penta prism (Pentagonal Dach prism)
4 Main mirror
5 Submirror
6 Mechanical shutter device
7 CCD
8 Clamp / CDS circuit
9 AGC (Automatic Gain Adjuster)
10 A / D converter
11 Video signal processing circuit
12 AF drive circuit
13 Aperture drive circuit
14 Mirror drive circuit
15 Focus detection sensor
16 Focus detection circuit
17 Shutter drive circuit
21 Switch sense circuit
22 Photometric sensor
23 Photometric circuit
24 Liquid crystal display drive circuit
25 LCD drive circuit
26 Memory controller
27 Buffer memory
28 memory
29 External interface
30 LCD in the viewfinder
31 Power supply
100 Camera body
114 Release button
115 main electronic dial,
116 Sub-electronic dial
117 Shooting mode selection button
118 AF mode selection button
119 Metering mode selection button
120 LCD monitor device
125 Dial resolution setting SW
140 External liquid crystal display device
200 Photography lens

Claims (7)

An electronic camera that can change the settings of parameters related to exposure,
Changing means for changing a step width when changing the setting value of the parameter relating to the exposure;
The control means for reflecting the change of the step width by the changing means when changing the setting values of a plurality of parameters other than the photographing sensitivity among the parameters relating to the exposure and not reflecting the setting values of the photographing sensitivity. And an electronic camera. The control means reflects the change of the step width by the changing means when changing the setting values of a plurality of parameters including bracket correction amounts in bracket shooting other than the shooting sensitivity among the parameters relating to the exposure. electronic camera according to claim 1, wherein the. The electronic camera according to claim 2, wherein the control unit reflects the change in the step width by the changing unit when changing the setting values of the shutter speed and the aperture value . 4. The electronic camera according to claim 2 , wherein the control unit reflects the change in the step width by the changing unit when changing a set value of an exposure correction amount with respect to an appropriate exposure . 5. Having an operation means operated when changing the setting value of the photographing sensitivity;
5. The electronic device according to claim 1, wherein the operation unit is operated when changing a setting value of at least one parameter other than the imaging sensitivity among the parameters relating to the exposure. 6. camera. 6. The electronic camera according to claim 1, wherein the step width is a minimum change amount when changing a setting value of a parameter relating to the exposure. An electronic camera control method comprising: changing means capable of changing a setting value of a parameter relating to exposure, and changing a step width when changing the setting value of the parameter relating to exposure,
The change of the step width by the changing means is reflected when changing the setting values of a plurality of parameters other than the shooting sensitivity among the parameters relating to the exposure, and is not reflected when changing the setting value of the shooting sensitivity. A control method for an electronic camera.

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