JP2024029115A - Imaging apparatus and control method and program for the same - Google Patents

Abstract

To make it possible to capture a video with proper exposure at a time when exposure change is performed while suppressing exposure fluctuations due to external disturbances.SOLUTION: A system control unit 50 of an imaging apparatus 100 performs detection of the brightness of a subject, acquisition of image capture settings at a time of image capture, detection of changes in the image capture settings, setting of an exposure tolerance range that allows deviation from a target exposure value, exposure control for automatic control of the exposure during image capture, changing of the exposure tolerance range, and comparison between the brightness of the subject and the exposure tolerance range. The system control unit 50 changes the exposure tolerance range when it detects a change in the image capture settings and changes the exposure if the subject brightness is out of the exposure tolerance range.SELECTED DRAWING: Figure 6

Description

The present invention relates to an imaging device, its control method, and program, and particularly relates to exposure control during imaging.

Many video cameras are equipped with a so-called automatic exposure control function that automatically changes brightness depending on the subject being imaged (for example, see Patent Document 1). In automatic exposure control, brightness is determined from brightness information of a subject, and various exposure parameters such as an aperture, an ND filter, a shutter, and a sensitivity are changed so that the brightness corresponds to an appropriate exposure. Since each of these exposure parameters has a different controllable resolution, the level at which the brightness of the subject can be brought close to the appropriate exposure depends on the resolution of each exposure parameter. For example, the coarsest resolution is stored in advance, and when the appropriate exposure falls within the range of the stored resolution, it is determined that the exposure is appropriate, and subsequent control is stopped. As an example, if the coarsest resolution is 1/8 stop, the proper exposure is within ±1/16 stop from the proper exposure.

Patent Application No. 2002-10136

If the brightness at the time of image capture is adjusted to follow the subject, the brightness of the entire screen will change due to changes in the brightness of the subject and changes in exposure, creating a sense of discomfort. When taking images for movies or news reports, this unnatural feeling is disliked, so images are often taken with manual exposure settings.

However, if the brightness of the subject changes gradually or suddenly while maintaining the manually set exposure value, overexposure or underexposure may occur. For example, when capturing an image with a fixed camera or a long camera, blown-out highlights or blown-out shadows may occur due to changes in the environment or the occurrence of an unexpected subject compared to the expected brightness.

SUMMARY OF THE INVENTION An object of the present invention is to provide an imaging device that can capture an image with proper exposure at the timing of changing exposure while suppressing fluctuations in exposure due to disturbances.

The imaging apparatus according to the present invention includes a photometry means for detecting the brightness of a subject, an acquisition means for acquiring imaging settings at the time of imaging, a detection means for detecting a change in the imaging settings, and a detection means for detecting a deviation from a target exposure value. a setting means for setting a permissible exposure range; an exposure control means for automatically controlling exposure during imaging; a changing means for changing the width of the permissible exposure range; and comparing means for comparing the brightness of the subject, when the detecting means detects a change in the imaging settings, the changing means changes the allowable exposure range, and the exposure controlling means changes the brightness of the subject. The present invention is characterized in that the exposure is changed when the exposure is out of the permissible range.

According to the present invention, it is possible to capture a stable image with appropriate exposure at the timing of exposure change while suppressing fluctuations in exposure due to disturbances.

1 is a block diagram showing a schematic configuration of an imaging device according to an embodiment of the present invention. 5 is a flowchart of exposure control according to the first embodiment. FIG. 2 is a schematic diagram showing the imaging environment, the subject, and the flow line of the imaging device. 4 is a diagram showing a relationship corresponding to FIG. 3 among elapsed time, photometric value, and target value in exposure control according to the first embodiment. FIG. It is a flowchart of exposure control concerning a 2nd embodiment. 4 is a diagram showing a relationship corresponding to FIG. 3 among elapsed time, photometric value, and target value in exposure control according to the second embodiment. FIG.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a block diagram showing a schematic configuration of an imaging device 100 according to an embodiment of the present invention. Here, the imaging device 100 is assumed to be a digital video camera that mainly shoots moving images.

The imaging device 100 includes an aperture 101, a barrier 102, an imaging lens 103, an ND filter 104, a D/A converter 13, a memory control section 15, an imaging section 22, an A/D converter 23, an image processing section 24, and a display section 28. , a memory 32, a gyro 40, and a system control section 50. The imaging device 100 also includes an I/F_18, a power supply section 30, a system memory 52, a system timer 53, a nonvolatile memory 56, a recording switch 61, a mode changeover switch 60, an operation section 70, and a power supply control section 80.

The imaging lens 103 includes a zoom lens, a focus lens, a shift lens, etc., and forms a subject image on the imaging unit 22 (image sensor). The aperture 101 adjusts the amount of light that enters the imaging section 22. The barrier 102 covers the imaging system including the imaging lens 103, the aperture 101, and the imaging unit 22, thereby preventing the imaging system from becoming dirty or damaged. The ND filter 104 is a light reduction filter that reduces the amount of light incident on the imaging unit 22 without affecting the color.

The imaging unit 22 includes an imaging device such as a CCD or a CMOS device that converts an optical image into an electrical signal. The imaging unit 22 also has functions such as controlling accumulation using an electronic shutter, changing analog gain, and changing readout speed. The A/D converter 23 converts the analog signal output from the imaging section 22 into a digital signal (image data) and outputs the digital signal. Note that the imaging section 22 may have the function of the A/D converter 23.

The image processing unit 24 processes the data from the A/D converter 23 and the memory control unit 15 by performing pixel interpolation processing, resizing processing such as reduction processing, luminance information, color information, characteristic object detection processing, and color processing. Performs various processing such as conversion processing, gamma correction processing, and digital gain addition processing. The image processing unit 24 also performs predetermined calculation processing using the image data from the A/D converter 23 and transmits the calculation results to the system control unit 50.

Image data output from the A/D converter 23 is written into the memory 32 via the image processing section 24 and the memory control section 15 or via the memory control section 15. The memory 32 stores image data output from the A/D converter 23 and image data used for display on the display unit 28. The memory 32 has a storage capacity sufficient to store moving images and audio for a predetermined period of time. Furthermore, the memory 32 also serves as a memory for displaying images (video memory).

The D/A converter 13 converts the image display data stored in the memory 32 into an analog signal and supplies it to the display unit 28 . The display section 28 includes a display device such as an LCD, and performs display according to the analog signal sent from the D/A converter 13. Note that the digital signal output from the A/D converter 23 and stored in the memory 32 is converted into analog by the D/A converter 13, and sequentially transferred to the display section 28 for display, thereby achieving the electronic viewfinder function. is realized, and through-image display can be performed.

The system control unit 50 is a microcomputer that has at least one processor (CPU) and controls the entire imaging device 100. The system control unit 50 performs exposure control, distance measurement control, white balance control, etc. based on the calculation results sent from the image processing unit 24. Specifically, the system control unit 50 performs TTL (through-the-lens) AF (autofocus) processing, AE (automatic exposure) processing, AWB (auto white balance) processing, and the like. Further, the system control unit 50 operates the shift lens of the imaging lens 103 or shifts the image by the image processing unit 24 in accordance with the movement or posture change of the imaging device 100 such as camera shake detected by the gyro 40. Perform image stabilization. The system control unit 50 performs display control by controlling the memory 32, the D/A converter 13, the display unit 28, and the like.

The nonvolatile memory 56 is a memory that can be electrically erased and stored, and for example, an EEPROM is used. The nonvolatile memory 56 stores constants, programs, etc. for the operation of the system control unit 50. The program includes a program for executing processes according to each of the flowcharts in FIGS. 2 and 5. A RAM is used as the system memory 52. In the system memory 52, constants and variables for the operation of the system control unit 50, programs read from the nonvolatile memory 56, and the like are expanded. The system timer 53 measures the time used for various controls and the time of a built-in clock.

The mode changeover switch 60, the recording switch 61, and the operation section 70 are operation means for inputting various operation instructions to the system control section 50, respectively. The mode changeover switch 60 changes the operation mode of the system control unit 50. The operation modes include, but are not limited to, a moving image recording mode, a still image recording mode, and a playback mode. The video recording mode and the still image recording mode further include a plurality of imaging modes such as an automatic imaging mode, an automatic scene determination mode, a manual mode, various scene modes with settings for each imaging scene, a program AE mode, and a custom mode. By operating the mode changeover switch 60, it is possible to directly switch to any of a plurality of imaging modes included in the video recording mode. Note that, after once switching to the video recording mode using the mode changeover switch 60, the mode may be switched to any one of a plurality of modes included in the video recording mode using another operating member.

The recording switch 61 switches between an imaging standby state and an imaging state. When the recording switch 61 is turned on, the system control unit 50 starts a series of operations from reading signals from the imaging unit 22 to writing image data (still image data, video data) to the storage medium 200. Each operation member of the operation unit 70 is assigned a function for each scene by touching various function icons displayed on the display unit 28, and operates as various function buttons. Examples of the function buttons include an end button, a return button, an image forwarding button, a jump button, a filter button, an attribute change button, and the like. For example, when the menu button is pressed, various setting menu screens are displayed on the display unit 28. The user can intuitively perform various settings using the menu screen displayed on the display unit 28, the cross keys in four directions (up, down, left, and right), and the SET button.

The power supply control unit 80 includes a battery detection circuit, a DC-DC converter, a switch circuit for switching the block to be energized, and the like, and detects whether or not a battery is attached, the type of battery, and the remaining battery level. Further, the power supply control unit 80 controls the DC-DC converter based on the detection results of the remaining battery level and the like and instructions from the system control unit 50, and supplies the necessary voltage to each block including the storage medium 200 for a necessary period. do. The power supply unit 30 is a primary battery such as an alkaline battery or a lithium battery, a secondary battery such as a NiCd battery, a NiMH battery, or a Li-ion battery, an AC adapter, or the like.

I/F_18 is an interface that enables communication between the storage medium 200 such as a memory card or hard disk, the external display device 300, etc., and the system control unit 50. The storage medium 200 is a memory card, a semiconductor memory, a magnetic disk, or the like that stores image data obtained by imaging, and may be built into the main body of the imaging device 100 or may be removable. The external display device 300 receives the image signal output from the A/D converter 23 and processed by the image processing unit 24 from I/F_18, applies monitor gamma, and displays the signal.

<First embodiment>
The exposure control method according to the first embodiment in the imaging device 100 will be described in detail. FIG. 2 is a flowchart of exposure control according to the first embodiment. Each process (step) indicated by an S number in the flowchart of FIG. 2 is a process in which the system control unit 50 loads a program stored in the nonvolatile memory 56 into the system memory 52 and controls the operation of each unit of the imaging device 100. This is realized by

FIG. 3 is a schematic diagram showing the imaging environment, the subject, and the flow line of the imaging device. Here, the imaging environment is roughly divided into two: outdoors on the left side of FIG. 3 and indoors on the right side of FIG. 3. The imaging device 100 chases and images a main subject that moves across such an imaging environment (main subject follow). Outdoor ambient light is sunlight, and indoor ambient light is illumination light. Here, it is assumed that during imaging, a signal to which intermediate gamma is applied is stored and the signal is output to the external display device 300. FIG. 4 is a diagram showing the relationship between the elapsed time, the photometric value, and the target value in the exposure control according to the first embodiment during imaging when the imaging environment changes as shown in FIG.

The flowchart in FIG. 2 will be explained with reference to FIGS. 3 and 4.

In S201, the system control unit 50 obtains a photometric value for the subject in order to obtain the brightness of the subject. For example, the average brightness value of the image data processed by the image processing unit 24 is acquired through the imaging system and the A/D converter 23.

In S202, the system control unit 50 acquires current camera information of the imaging device 100. The camera information includes information on parameters (hereinafter referred to as "imaging settings") that affect the image quality, such as the brightness and color of the imaged image. For example, the system control unit 50 obtains the WB gain applied by the image processing unit 24 for white balance adjustment. The WB gain is a value that changes when the auto white balance function calculates the white balance by obtaining an evaluation value from the subject or when the white balance setting is changed by a user operation, and is one of the imaging settings. The WB gain to be acquired may be, for example, an R gain value and a B gain value, or a ratio thereof. Alternatively, it may be the filter density of the ND filter 104, the detection result of an imaging scene executed by the system control unit 50 using the imaging result, the likelihood of an assumed imaging scene, or the like. Here, it is assumed that an imaging setting of R gain value/B gain value=2 is acquired.

In S203, the system control unit 50 saves the camera information acquired in S202 as current camera information. At that time, the saved camera information is saved as the previous camera information. Here, it is assumed that the previous camera information includes an imaging setting of R gain value/B gain value=1.9.

In S204, the system control unit 50 determines whether the imaging settings have changed. That is, the current imaging settings saved in S203 are compared with the previous imaging settings to determine whether the imaging settings have changed. If the system control unit 50 determines that the imaging settings have changed (YES in S204), it advances the process to S205, and if it determines that the imaging settings have not changed (NO in S204), it advances the process to S206.

In the above example, the value of the R gain value/B gain value, which is one of the current imaging settings acquired in S202, is '2', whereas the value of the previous R gain value/B gain value saved in S203 is '2'. Since the B gain value is '1.9' and the values are different, it is determined that the imaging settings have changed. Here, the objects to be controlled by the automatic exposure control are the aperture 101, the shutter, the gain (gain value independent of color), and ND, and the change in the WB gain is not the object to be controlled by the automatic exposure control. The following two causes can be considered for the change in the WB gain in this case, but it does not matter which one is the cause. One is a case where the photographer manually changes the WB gain because the imaging scene changes (in the example of FIG. 3, the main subject moves from outdoors to indoors). Another is that the color evaluation value changes due to the operation of the AWB function in response to a change in the imaging scene, and this is a case where the WB gain is changed by the system control unit 50. Note that examples of exposure changes that are not controlled by automatic exposure control include various manual operations, such as manual insertion and removal of the ND filter 104 from the incident optical path.

Note that here, it is determined whether the values of the imaging settings match or do not match, but it may be determined whether the amount of change in the imaging settings is within a preset threshold range. Further, the distance of a feature vector using some other imaging settings as one of the parameters may be compared with a predetermined threshold value.

In S205, the system control unit 50 reduces the exposure tolerance range, and then advances the process to S207. In S206, the system control unit 50 expands the allowable exposure range, and then advances the process to S207.

Looking at the processes of S205 and S206 in FIG. 4, first, in the area before time T1, no change in the imaging settings has been detected, so the allowable exposure range is wide. Specifically, The state allows up to ±2 steps with respect to the exposure target value.

When the process progresses from S204 to S205 at time T1 (when the imaging settings other than the target parameters of automatic exposure control change), the allowable exposure range is reduced (narrowed). Here, at time T1, the exposure tolerance range is reduced from the previous ±2 stops to ±1/2 stops. Scenes in which imaging settings other than parameters subject to automatic exposure control change are scenes in which the photographer intends to capture an image with an appropriate exposure, such as when the photographer changes the WB gain. Control will be performed to ensure proper exposure. Therefore, automatic exposure control is enabled at time T1.

The expansion of the permissible exposure range at time T2 is performed when the determination in S204 is performed while the permissible exposure range is ±1/2 stops (after the permissible exposure range is reduced to ±1/2 stops at time T1). This indicates that the allowable exposure range has been expanded as a result of the process proceeding to S206.

When changing the exposure tolerance range, the maximum range is the allowable difference from the predetermined exposure target value, and the minimum range is the control tolerance range that depends on the control resolution and control error of each exposure parameter. is also set to be wider. After time T2, automatic exposure control is disabled in order to avoid frequent changes in the brightness of the entire screen due to changes in subject brightness and exposure changes.

Note that the exposure permissible range is not reduced beyond the minimum range, and if the processing proceeds to S205 with the exposure permissible range already reaching the minimum range, it is maintained at the minimum range. Similarly, the allowable exposure range is not expanded beyond the maximum range, and if the process proceeds to S206 with the allowable exposure range already reaching the maximum range, it is maintained at the maximum range. The maximum range and the minimum range may each be settable by a user operation using the operating unit 70 within a range that can be set by the imaging device 100. The exposure permissible range may be changed by switching between a wide range and a narrow range in one change, or by setting a small amount of change in one change and controlling the exposure range to change gradually.

In S207, the system control unit 50 compares the exposure target value and the photometric value obtained in S201. For example, the difference ΔY between the brightness average value Yn (photometric value) and the brightness target value Yt is expressed by the following formula (1). As can be seen from this formula, ΔY increases by 1 when the brightness is doubled. In FIG. 4, the brightness target value Yt (target value) is shown by a broken line, and ΔY is shown by a solid line.
[Number 1]
ΔY=log2(Yn/Yt)...Formula (1)

In S208, the system control unit 50 determines whether the brightness of the subject (the photometric value obtained in S201) is within an allowable range. For example, it is determined whether ΔY is within the allowable brightness range reduced in S205. In this case, if the range of ±1/2 steps is allowed, it is determined that ΔY is within the allowable range if ΔY is -1/2 steps or more and less than +1/2 steps. The determination in S208 is to determine whether ΔY (solid line) is included in the exposure target value range at an arbitrary time in FIG. If the system control unit 50 determines that the photometric value is not within the allowable range (NO in S208), the process proceeds to S209, and if the system control unit 50 determines that the photometric value is within the allowable range (YES in S208), the process continues. Proceed to S210.

In S209, the system control unit 50 enables automatic exposure control regarding the exposure control mode, and then advances the process to S211. On the other hand, in S209, the system control unit 50 disables automatic exposure control regarding the exposure control mode, and then advances the process to S211. Here, the exposure control mode indicates whether automatic exposure control is enabled or disabled. In FIG. 4, the automatic exposure control invalidation time period ( ~T1, T2~) and automatic exposure control effective time period (T1~T2).

In S211, the system control unit 50 determines whether automatic exposure control is effective. If the system control unit 50 determines that automatic exposure control is valid (YES in S211), the process proceeds to S212, and if it determines that automatic exposure control is invalid (NO in S211), it ends this process. let For example, when automatic exposure control is changed from disabled to enabled at time T1 in the process in S209, the process proceeds to S212. On the other hand, if automatic exposure control is disabled, the process ends without changing the exposure.

In S212, the system control unit 50 determines exposure parameters to be subjected to automatic exposure control. The exposure parameter variation pattern is determined in advance according to the program AE mode. For example, after changing from a small aperture state to F4.0, the shutter speed is changed from 1/250 to 1/60, and after that, after changing from F4.0 to open, the sensitivity is increased from the lowest sensitivity to the highest sensitivity. How wide open or small the aperture can be set, how far the minimum sensitivity and maximum sensitivity can be set, etc. are determined by the status of the imaging device 100 (zoom position, focus position, presence or absence of a filter, etc.) and settings related to exposure (sensitivity expansion function). and gamma settings, etc.).

Based on the state of the imaging device 100 and settings related to exposure, information such as aperture and sensitivity is applied to the above exposure parameter variation pattern. For example, the subject brightness BV can be determined by the following equation (2) using the aperture value AV, shutter speed TV, and ISO sensitivity SV. Note that each value of BV, AV, TV, and SV is an APEX unit conversion value.
[Number 2]
BV=AV+TV-SV...Formula (2)

In S213, the system control unit 50 changes the exposure and ends this process. Specifically, the system control unit 50 converts the exposure parameters determined in S212 into control values that can be set for the aperture 101, ND filter 104, imaging unit 22, A/D converter 23, and image processing unit 24. and send control values to each. In this way, the aperture, ND, shutter speed, and ISO sensitivity are changed to obtain the desired exposure.

Applying the above control to FIG. 4, automatic exposure control is disabled in the time period before time T1, and therefore no exposure change is performed. Automatic exposure control is enabled during the period from time T1 when a change in imaging settings is detected to time T2, and exposure is automatically changed so that ΔY falls within the exposure tolerance range. When ΔY falls within the exposure tolerance range at time T2, automatic exposure control is switched to invalidity. After time T2, no change in imaging settings is detected, and therefore no exposure change is performed.

As explained above, according to the exposure control according to the first embodiment, the permissible exposure range is switched according to changes in the imaging settings, and the automatic exposure control is enabled or disabled according to the comparison result between the photometric value of the subject and the permissible exposure range. Toggle between disabled and disabled. This makes it possible to change exposure in scenes where exposure change is desired while minimizing exposure fluctuations.

<Second embodiment>
In the first embodiment, the frequency of exposure changes is reduced by determining whether automatic exposure control is enabled or disabled based on changes in imaging settings. On the other hand, even if the imaging settings do not change, it may be desirable to perform exposure control if the exposure deviates significantly from the exposure target value. Therefore, in the second embodiment, while performing automatic exposure control, the allowable exposure range is changed when a change in the imaging settings is detected, and the exposure range is maintained within a certain range from the exposure target value even when the imaging settings do not change. An example of changing the allowable exposure range will be explained below.

FIG. 5 is a flowchart of exposure control according to the second embodiment. In each process (step) indicated by an S number in the flowchart of FIG. 5, the system control unit 50 loads a program stored in the nonvolatile memory 56 into the system memory 52 and executes it to control the operation of each unit of the imaging device 100. This is achieved by FIG. 6 is a diagram showing the relationship between elapsed time, photometric value, and target value in exposure control according to the second embodiment during imaging when the imaging environment changes as shown in FIG. Note that the block configuration of the imaging device 100 is the same as that in FIG. 1, so a description thereof will be omitted.

Each process from S501 to S508 is the same as each process from S201 to S208 in the flowchart of FIG. 2, so the description thereof will be omitted. If the system control unit 50 determines that the photometric value is not within the exposure tolerance range (NO in S508), the process proceeds to S509, and if it determines that the photometric value is within the exposure tolerance range (YES in S508), This process ends without changing the exposure.

In S509, the system control unit 50 determines exposure parameters. The processes in S509 and S510 are the same as the processes in S212 and S203 in the flowchart of FIG. 2, so the description thereof will be omitted. This process ends at S510.

The processing of S508 to S509 will be explained with reference to FIG. In FIG. 6, in the time period before time T3, the exposure tolerance range is maintained in a wide state, and the magnitude of ΔY is allowed within the exposure tolerance range. The permissible exposure range narrows during the period from time T3 to T4 when a change in the imaging settings is detected, and the exposure is controlled so that ΔY falls within the narrow exposure target value range. At time T4, no change in the imaging settings is detected, and accordingly, control to expand the permissible exposure range is started. Here, no change in the imaging settings is detected after time T4, the allowable exposure range reaches the maximum range at time T5, and the allowable exposure range is maintained at the maximum range in the subsequent time period, so that the frequency of exposure changes is is kept low.

As explained above, according to the exposure control according to the second embodiment, when the imaging settings do not change, the difference between the exposure target value and the metered value is kept within a certain range by setting a wide exposure tolerance range. However, it is possible to express changes in the brightness of the subject as they are. When the imaging settings change, the allowable exposure range is set narrower and exposure control is performed to reduce the difference between the exposure target value and the metered value. can be approached. In this way, by changing the exposure permissible range depending on whether there is a change in the imaging settings and performing exposure control within the changed exposure permissible range, it is possible to reduce the frequency of exposure changes.

Although the present invention has been described above in detail based on its preferred embodiments, the present invention is not limited to these specific embodiments, and the present invention may take various forms without departing from the gist of the present invention. included. Some of the embodiments described above may be combined as appropriate. For example, in the embodiments described above, the present invention has been explained using a digital video camera as an example, but the present invention also applies to the video shooting function of a digital still camera or the video shooting function of a portable electronic device equipped with an imaging function such as a smartphone. It can be used as a function.

22 Imaging unit 24 Image processing unit 50 System control unit 100 Imaging device 103 Imaging lens 104 ND filter

Claims (7)

A photometer that detects the brightness of the subject;
an acquisition means for acquiring imaging settings at the time of imaging;
detection means for detecting a change in the imaging settings;
a setting means for setting an exposure tolerance range that allows deviation from the exposure target value;
an exposure control means that automatically controls exposure during image capture;
Changing means for changing the width of the exposure tolerance range;
Comparing means for comparing the brightness of the subject and the permissible exposure range,
When the detection means detects a change in the imaging settings, the changing means changes the allowable exposure range;
The imaging device is characterized in that the exposure control means changes the exposure when the brightness of the subject is outside the permissible exposure range. When the detecting means detects a change in the imaging setting, the changing means reduces the allowable exposure range, and when the detecting means does not detect a change in the imaging setting, the changing means reduces the allowable exposure range. The imaging device according to claim 1, wherein the imaging device enlarges the image. Imaging according to claim 1 or 2, characterized in that the minimum range of the exposure tolerance range is wider than a control tolerance range that depends on a resolution of a controlled object and a control error in automatic exposure control by the exposure control means. Device. 4. The imaging apparatus according to claim 3, wherein the control target is an aperture value, a shutter speed, a gain, and an ND. 2. The setting means is characterized in that the setting means does not expand the permissible exposure range beyond a predetermined maximum range, and does not reduce the permissible exposure range beyond a predetermined minimum range. 4. The imaging device according to any one of 4. A method for controlling an imaging device, the method comprising:
A metering step that detects the brightness of the subject,
an acquisition step of acquiring imaging settings at the time of imaging;
a detection step of detecting a change in the imaging settings;
a setting step for setting an exposure tolerance range that allows deviation from the exposure target value;
an exposure control step that automatically controls exposure during image capture;
a changing step of changing the width of the exposure tolerance range;
a comparison step of comparing the brightness of the subject and the exposure tolerance range,
In the detection step, if a change in the imaging settings is detected, in the changing step, the exposure tolerance range is changed;
A method for controlling an imaging apparatus, wherein in the exposure control step, the exposure is changed when the brightness of the subject is outside the permissible exposure range. A program that causes a computer to function as each means of the imaging device according to claim 1.

Images