JP2003189175A - Electronic camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic camera that revises imaging sensitivity only when proper exposure cannot be obtained by setting imaging sensitivity. <P>SOLUTION: An arithmetic circuit 101 selects a mode to be a program automatic exposure arithmetic mode (P), an aperture precedence automatic exposure arithmetic mode (A), a shutter speed precedence (exposure time precedence) automatic exposure arithmetic mode (S), or a manual exposure arithmetic mode (M) in response to an operation signal from an exposure mode setting operation member 110. The arithmetic circuit 101 allows a display device 115 to display any of the 'P', 'A', 'S' and 'M' corresponding to the exposure arithmetic mode. When an imaging sensitivity automatic revision mode is set, the arithmetic circuit 101 changes display corresponding to the exposure arithmetic mode from lighting display into blinking display. The arithmetic circuit 101 revises the imaging sensitivity set in response to the exposure deviation only when no proper exposure can be obtained. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic camera for picking up a subject image by an image pickup device.

[0002]

2. Description of the Related Art In order to obtain an appropriate exposure amount with a camera, the aperture value AV of the taking lens and the shutter speed (exposure time) T
There is known an apex operation for performing exposure calculation by the following expression (1) using V, subject brightness BV, and exposure sensitivity SV.

## EQU1 ## EV = AV + TV = BV + SV (1) where EV is the exposure amount. In the case of a film camera, since the SV is determined by the sensitivity of the film used, the aperture value AV and the shutter speed TV are calculated according to the subject brightness BV. In the case of an electronic camera, when the exposure sensitivity SV of the image pickup apparatus is changeable, the aperture value AV, the shutter speed TV, and the exposure sensitivity SV are calculated according to the subject brightness BV.

[0003]

Generally, in an electronic camera, when the exposure sensitivity SV is increased, the noise superimposed on the image signal increases and the image quality deteriorates. Therefore, if the exposure sensitivity SV can be changed, the aperture value AV and the shutter speed T
In the exposure calculation mode in which V is preferentially set, the exposure sensitivity SV is automatically changed so that the calculation result is a proper exposure. As a result, there is a problem that the S / N ratio of the image deteriorates contrary to the intention of the photographer.

An object of the present invention is to provide an electronic camera in which the exposure sensitivity is changed when proper exposure cannot be obtained with the set exposure sensitivity.

[0005]

(1) An electronic camera according to the present invention includes an image pickup device for picking up a subject image through a taking lens, a luminance detection device for detecting the subject luminance, and an exposure sensitivity set in the image pickup device. , The exposure time set in the image pickup device, the aperture value set in the shooting lens, and the subject brightness detected by the brightness detection device are used to perform exposure calculation, and the exposure time and A first arithmetic circuit that calculates the control exposure by changing at least one of the aperture values, and a first arithmetic circuit that changes the exposure sensitivity and further performs the exposure calculation when the calculation result by the first arithmetic circuit is different from the proper exposure. The above-mentioned object is achieved by including a control circuit for controlling one arithmetic circuit. (2) The invention according to claim 2 is the electronic camera according to claim 1, wherein the exposure sensitivity set in the image pickup device,
The exposure calculation is performed using the exposure time set in the imaging device, the aperture value set in the shooting lens, and the subject brightness detected by the brightness detection device. It further comprises a second arithmetic circuit for changing at least one of the time and the aperture value to calculate the control exposure, and a selection operation means for selecting one of the first arithmetic circuit and the second arithmetic circuit. Is characterized by. (3) According to the invention described in claim 3, in the electronic camera described in claim 2, the first arithmetic circuit and the second arithmetic circuit set the exposure time and the aperture value to predetermined values so that proper exposure can be obtained. Set the program exposure calculation mode that calculates the control exposure by changing the combination, and the aperture value priority exposure calculation mode that calculates the control exposure by changing the exposure time so that the proper exposure can be obtained with the set aperture value. Exposure time priority exposure calculation mode that calculates the control exposure by changing the aperture value so that the proper exposure can be obtained with the set exposure time, and manual exposure calculation that calculates the control exposure with the set exposure time and aperture value And a mode. (4) The invention according to claim 4 is the electronic camera according to claim 3, wherein the control circuit performs exposure when the first arithmetic circuit performs an exposure calculation in a program exposure calculation mode or an aperture value priority exposure mode. When the calculation result differs from the proper exposure due to the control limit of time, the exposure sensitivity is changed according to the deviation between the calculation result and the proper exposure, and the first calculation circuit is controlled so as to further perform the exposure calculation. To do. (5) The invention according to claim 5 is the electronic camera according to claim 3, wherein the control circuit controls the aperture value when the first arithmetic circuit performs the exposure calculation in the exposure time priority exposure calculation mode. When the calculation result is different from the proper exposure, the first calculation circuit is controlled so that the exposure sensitivity is changed according to the deviation between the calculation result and the proper exposure to further perform the exposure calculation. (6) The invention according to claim 6 is the electronic camera according to claim 3, wherein the control circuit has a calculation result different from the proper exposure when the first calculation circuit performs the exposure calculation in the manual exposure calculation mode. In this case, the first arithmetic circuit is controlled so that the exposure sensitivity is changed in accordance with the deviation between the arithmetic result and the proper exposure to further perform the exposure arithmetic. (7) The invention according to claim 7 is the electronic camera according to claim 3, which is one of a program exposure calculation mode, an aperture value priority exposure calculation mode, an exposure time priority exposure calculation mode, and a manual exposure calculation mode. A display device that displays an exposure calculation mode indicating whether the exposure calculation is performed in the calculation mode, and a case where the first calculation circuit is selected by the selection operation means and a case where the second calculation circuit is selected. And a display control device for controlling the display device so as to change the mode of the exposure calculation mode display. (8) The invention according to claim 8 is the electronic camera according to claim 7, wherein the display control device blinks when the first arithmetic circuit is selected, and the second arithmetic circuit is selected. It is characterized in that the display device is controlled so as to perform a lighting display when the display is turned on. (9) The invention according to claim 9 is the electronic camera according to claim 3, which is one of a program exposure calculation mode, an aperture value priority exposure calculation mode, an exposure time priority exposure calculation mode, and a manual exposure calculation mode. A display device that displays an exposure calculation mode indicating whether or not the exposure calculation is performed in the calculation mode, and a mode of the exposure calculation mode display depending on whether the exposure sensitivity is changed by the first calculation circuit or not. And a display control device that controls the display device to change the display device. (10) The invention according to claim 10 is the electronic camera according to claim 9, wherein the display control device displays a blink when the exposure sensitivity is changed and a display when the exposure sensitivity is not changed. The display device is controlled so as to perform.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of an electronic camera according to an embodiment of the present invention. In FIG. 1, the arithmetic circuit 101 is composed of a microcomputer or the like. The arithmetic circuit 101 inputs a signal output from each block described below, performs a predetermined arithmetic operation, and outputs a control signal to each block based on the arithmetic result. The CCD 102 constitutes an image sensor. CCD 102
Takes an image of the subject light that has passed through the taking lens 103, and outputs an image pickup signal to the image pickup signal processing circuit 105.
The CCD 102 is driven at a predetermined operation timing by the drive signal output from the drive circuit 104. Here, the CCD 102 sets the imaging sensitivity (exposure sensitivity) to ISO1.
It is configured such that it can be set in a predetermined step within a range from 00 to ISO1600.

The image pickup signal processing circuit 105 includes a correlated double sampling circuit for removing reset noise of the image pickup signal and an A / D conversion circuit for converting an analog image pickup signal into a digital signal. The image data digitized by the imaging signal processing circuit 105 is output to the recording circuit 106. The recording circuit 106 sequentially inputs the image data signal-processed by the imaging signal processing circuit 105 and temporarily stores the image data. The recording medium 107 is composed of a flash memory or the like. The recording medium 107 is driven and controlled by a control signal output from the controller 108, and records the image data temporarily stored in the recording circuit 106.

The sensitivity setting operation member 109 outputs an operation signal to the arithmetic circuit 101 in response to an image pickup sensitivity setting operation. The arithmetic circuit 101 sets the above-described image pickup sensitivity of the CCD 102 according to the image pickup sensitivity setting operation signal. The exposure mode setting operation member 110 has a program auto exposure calculation mode (P), an aperture value priority auto exposure calculation mode (A), a shutter speed priority (exposure time priority) auto exposure calculation mode (S) according to the exposure mode setting operation. , And the operation signal for switching to the manual exposure calculation mode (M)
Output to 01.

The program automatic exposure calculation mode is an exposure calculation mode in which the control exposure is calculated by changing the exposure time and the aperture value of the image pickup apparatus 1 in a predetermined combination so as to obtain a proper exposure. The aperture value priority auto-exposure calculation mode is a calculation mode in which the control exposure is calculated by changing the exposure time so that the proper exposure can be obtained with the set aperture value. The exposure time priority auto exposure calculation mode is a calculation mode in which the control exposure is calculated by changing the aperture value so that the proper exposure can be obtained within the set exposure time. The manual exposure calculation mode is a calculation mode in which the control exposure is calculated with the set exposure time and aperture value.

The shutter speed setting operation member 111 outputs an operation signal to the arithmetic circuit 101 according to the shutter speed setting operation. The arithmetic circuit 101 sets an opening time of a shutter, which will be described later, according to the shutter speed setting operation signal, and controls the exposure time of the CCD 102 described above. Here, the shutter speed (exposure time) can be set in a predetermined step within a range of 1 second to 1/1000 second. The aperture setting operation member 112 outputs an operation signal to the arithmetic circuit 101 according to the setting operation. The arithmetic circuit 101 sets an aperture value described later according to the aperture setting operation signal. Aperture value is F
It is configured such that it can be set in predetermined steps in the range of 2.8 to F22.

The custom setting operation member 113 is
An operation signal is output to the arithmetic circuit 101 according to the custom setting operation. The arithmetic circuit 101 sets or cancels the imaging sensitivity automatic change mode according to the custom setting operation signal. In the imaging sensitivity automatic change mode, the control exposure is calculated by automatically changing the imaging sensitivity SV according to the exposure deviation ΔEV so that a proper exposure can be obtained. The exposure deviation ΔEV is the difference between the control exposure and the proper exposure. When the imaging sensitivity automatic change mode is canceled, the control exposure is calculated so that the proper exposure can be obtained with the set imaging sensitivity SV.

The release switch 114 outputs a release operation signal to the arithmetic circuit 101 in conjunction with a release operation button (not shown). The display device 115 includes the arithmetic circuit 101.
The shutter speed, aperture value, imaging sensitivity, exposure calculation mode, etc. are displayed according to the command. The photometric device 116 detects the subject brightness and outputs a detection signal to the arithmetic circuit 101. The motor drive circuit 117 drives and controls the sequence motor 118 according to a command from the arithmetic circuit 101. The sequence motor 118 constitutes a sequence driving device (not shown),
The mirror up / down (not shown) is driven, the diaphragm (not shown) is driven, and the shutter is charged.

The shutter control circuit 121 includes a shutter 12
The holding and releasing of the first and second curtains (not shown) are controlled respectively. The aperture position detection device 123 detects the aperture position corresponding to the aperture value and outputs a detection signal to the arithmetic circuit 101. The diaphragm locking device 124 locks the diaphragm being driven and stops the diaphragm at a predetermined diaphragm value. The sequence switch 119 constitutes a sequence driving device (not shown),
It is a switch that generates the brake control timing of the sequence motor 118.

The present invention is characterized in that when a proper exposure cannot be obtained with the image pickup sensitivity set in the electronic camera, the control exposure is calculated by automatically changing the image pickup sensitivity so as to obtain the proper exposure. Have.

The camera operation processing performed by the arithmetic circuit 101 of the electronic camera will be described with reference to the flowcharts of FIGS. 2 and 3. The program according to the flowcharts of FIGS. 2 and 3 is activated when a battery (not shown) is loaded into the electronic camera. In step S1 of FIG. 2, the arithmetic operation circuit 101 makes the following initial settings. Set sensitivity SVs to 7 (ISO400) and set shutter speed TVs to 7
Set the aperture value AVs to 5 (F5.6) at (1/125 seconds)
Then, the mode parameter Mp is set to 1 and the custom setting flag S is set to 0, and the process proceeds to step S2.

Here, Apex values are used for SVs, TVs, and AVs. The range of the set sensitivity SVs of the electronic camera according to the present embodiment is 5 ≦ SVs ≦ 9, and I
It corresponds to SO100 to ISO1600. The range of the set shutter speed TVs is 0 ≦ TVs ≦ 10, that is, 1 second to 1/1000 second. The range of the set aperture value AVs is 3
≦ AVs ≦ 9, that is, F2.8 to F22. The mode parameter Mp indicates the exposure calculation mode, and Mp = 1
Is a program auto exposure calculation mode (P), Mp = 2 is a shutter speed priority (exposure time priority) auto exposure calculation mode (S), Mp = 3 is an aperture value priority auto exposure calculation mode (A), Mp = 4 is manual Exposure calculation mode (M)
, Respectively. Custom setting flag S
Indicates that S = 1 corresponds to the setting of the imaging sensitivity automatic change mode, and S = 0 corresponds to the cancellation of the imaging sensitivity automatic change mode.

In step S2, the arithmetic circuit 101
Performs photometry for calculating the subject brightness BV based on the detection signal input from the photometry device 116, and proceeds to step S3. In step S3, the arithmetic operation circuit 101 performs an exposure arithmetic operation process, and proceeds to step S4. Details of the exposure calculation process will be described later. In step S4, the arithmetic operation circuit 101 causes the control shutter speed TVc, the control aperture value AVc, and the set sensitivity SVs calculated by the exposure operation.
Is displayed on the display device 115, and the process proceeds to step S5. Details of the display process will be described later.

In step S5, the arithmetic circuit 101
Performs each setting process according to the operation signal input from each setting operation member 109 to 113, and proceeds to step S6.
Details of the setting process will be described later. In step S6, the arithmetic operation circuit 101 determines whether or not the release switch 114 has been operated. The arithmetic operation circuit 101 makes an affirmative decision in step S6 if an operation signal has been input from the release switch 114 to proceed to step S7, and makes a negative decision in step S6 if no operation signal has been input from the release switch 114 to proceed to step S2. Return.

In step S7, the arithmetic circuit 101
Outputs a command to the shutter control circuit 121 to energize a magnet (not shown) of the shutter 122 to hold the front curtain and the rear curtain. In step S8, the arithmetic circuit 101
Outputs a command to the motor drive circuit 117, causes the sequence motor 118 to start normal rotation, and proceeds to step S9.
As a result, the mirror up of the mirror (not shown) and the aperture stop are started. In step S9, the arithmetic operation circuit 101 obtains the drive aperture value AVk based on the detection signal input from the aperture position detection device 123, and determines whether AVk ≧ AVc is satisfied with the control aperture value AVc. The arithmetic operation circuit 101 makes an affirmative decision in step S9 if AVk ≧ AVc is true to proceed to step S10, and makes a negative decision in step S9 if AVk ≧ AVc is not true. When a negative determination is made, the narrowing is continued and the determination processing is repeated.

In step S10, the arithmetic circuit 101
Outputs a command to the aperture locking device 124 to lock the aperture, and proceeds to step S11. In step S11,
The arithmetic circuit 101 determines whether or not the mirror-up is completed. The arithmetic circuit 101 includes a sequence switch 119.
When an ON signal is input from the step S11, an affirmative decision is made in step S11, the operation proceeds to step S12, and the sequence switch 119
If the ON signal is not input from, the negative determination is made in step S11. When a negative determination is made, the mirror up is continued and the determination processing is repeated.

In step S12, the arithmetic circuit 101
Outputs a command to the motor drive circuit 117, stops the sequence motor 118, and proceeds to step S13. A sequence driving device (not shown) is configured such that the stop of the diaphragm is stopped by the stop locking device 124 before the end of the mirror up. In step S13,
The arithmetic circuit 101 causes the drive circuit 104 to start generating a drive signal to start driving the CCD 102, and step S1
Go to 4. In step S14, the arithmetic circuit 101
Waits for a predetermined time and goes to step S15. The predetermined time is a time required for the CCD 102 to be stably driven.

In step S15, the arithmetic circuit 101
Outputs a command to the shutter control circuit 121 to release the power supply to the magnet (not shown) of the shutter 122 to release the front curtain holding, and the process proceeds to step S16 in FIG. As a result, the shutter front curtain starts running, and charge is accumulated in the CCD 102 according to the intensity of the subject light reaching the image pickup surface of the CCD 102. In step S16, the arithmetic operation circuit 101 waits for a time corresponding to the control shutter speed TVc and proceeds to step S17. Step S1
7, the arithmetic circuit 101 has a shutter control circuit 12
1 is output, the power supply to the magnet (not shown) of the shutter 122 is released to release the rear curtain holding, and step S
Proceed to 18. As a result, the shutter rear curtain starts to run, and the subject light to the CCD 102 is blocked, whereby the charge accumulation in the CCD 102 ends.

In step S18, the arithmetic circuit 101
Waits for a predetermined time and proceeds to step S19. The predetermined time is the time required for the trailing curtain to completely block the image pickup area of the CCD 102 and to finish traveling. In step S19, the arithmetic operation circuit 101 outputs a command to the motor drive circuit 117, causes the sequence motor 118 to start reverse rotation, and proceeds to step S20. As a result, the mirror down of the mirror (not shown) and the opening return of the diaphragm are started. In step S20, the arithmetic circuit 101
Outputs a command to the imaging signal processing circuit 105, and the CCD 1
The reading of the image signal is started from 02, and step S2
Go to 1.

In step S21, the arithmetic circuit 101
Causes the drive circuit 104 to stop generating drive signals and
The driving of D102 is completed, and the process proceeds to step S22. In step S22, the arithmetic operation circuit 101 sets 0 in each of the flag D and the flag P, and proceeds to step S23. The flag D is a flag which is set to 1 when the mirror down operation is completed. The flag P is a flag that is set to 1 when the image pickup signal processing ends. When both the flag D and the flag P are set to 1, it is determined that the series of image capturing processes has ended.

In step S23, the arithmetic circuit 101
Causes the imaging signal processing circuit 105 to start signal processing, and proceeds to step S24. In step S24, the arithmetic operation circuit 101 determines whether or not the image pickup signal processing has been completed. The arithmetic operation circuit 101 makes an affirmative decision in step S24 if the signal processing by the imaging signal processing circuit 105 has ended, proceeds to step S27, and makes a negative decision in step S24 if the signal processing by the imaging signal processing circuit 105 has not ended. Then, the process proceeds to step S25.

In step S25, the arithmetic circuit 101
Determines whether the flag D is 1. Arithmetic circuit 101
Affirmatively determines step S25 when D = 1 and returns to step S24, and when D ≠ 1, negatively determines step S25 and proceeds to step S26. In step S26, the arithmetic operation circuit 101 determines whether or not the mirror down is completed. When the ON signal is input from the sequence switch 119, the arithmetic operation circuit 101 makes an affirmative decision in step S26 and the operation proceeds to step S30. When the ON signal is not input from the sequence switch 119, the arithmetic circuit 101 proceeds to step S2.
A negative decision is made at 6 and the operation proceeds to step S29.

In step S30, the arithmetic circuit 101
Outputs a command to the motor drive circuit 117, stops the sequence motor 118, and proceeds to step S31. In step S31, the arithmetic operation circuit 101 sets the flag D to 1
Is set and the process proceeds to step S32. In step S32, the arithmetic operation circuit 101 determines whether the flag P is 1 or not. The arithmetic operation circuit 101 performs step S3 when P = 1.
If the result is affirmative, the process proceeds to step S33. If P ≠ 1, the process makes a negative determination in step S32 and the process returns to step S24. In step S33, the arithmetic operation circuit 101 outputs a command to the controller 108 to store the image data in the flash memory 107, and returns to step S2 in FIG.

On the other hand, in step S27 to which the operation proceeds after making an affirmative decision in step S24, the arithmetic operation circuit 101 makes the flag P
Is set to 1, and the process proceeds to step S28. Step S2
At 8, the arithmetic circuit 101 determines whether or not the flag D is 1. The arithmetic operation circuit 101 makes an affirmative decision in step S28 if D = 1 to proceed to step S33, whereas it makes a negative decision in step S28 if D ≠ 1 to proceed to step S26.

In step S29, which proceeds after making a negative decision in step S26, the arithmetic operation circuit 101 determines whether the flag P is 1 or not. The arithmetic operation circuit 101 makes an affirmative decision in step S29 if P = 1 to return to step S26, and makes a negative decision in step S29 if P ≠ 1 to return to step S24.

Details of the exposure calculation processing will be described with reference to FIGS.
This will be described with reference to the flowchart in FIG. In step S101 of FIG. 4, the arithmetic operation circuit 101 uses EV = BV + S
After calculating Vs, the process proceeds to step S102. However, EV
Is the exposure value, BV is the subject brightness, and SVs is the set imaging sensitivity. Here, the set image pickup sensitivity SVs is the image pickup sensitivity set by the operation of the sensitivity setting operation member 109.
In step S102, the arithmetic operation circuit 101 determines whether or not the mode parameter Mp = 1. Arithmetic circuit 101
Is an affirmative decision in step S102 if Mp = 1 (program auto exposure calculation mode), step S103
When Mp ≠ 1, the determination is negative in step S102, and the process proceeds to step S131 in FIG.

In step S103, the arithmetic circuit 10
1 calculates AVc = EV / 2−1 to perform step S10.
Go to 4. However, AVc is a control aperture value. In step S104, the arithmetic operation circuit 101 determines whether AVc <3 holds. The arithmetic circuit 101 is AVc
If <3 is satisfied (the control aperture value is smaller than F2.8), an affirmative decision is made in step S104 and step S105.
Proceed to step S10 if AVc <3 is not satisfied.
A negative determination of 4 is made and the process proceeds to step S107. Step S
In 105, the arithmetic operation circuit 101 determines that the control aperture value AVc
Is set to 3, and the process proceeds to step S106. As a result, the control aperture value is set to F2.8 which is the lower limit of the setting range.

In step S106, the arithmetic circuit 10
1 calculates TVc = EV-3 and proceeds to step S111. However, TVc is a control shutter speed. In step S111, the arithmetic operation circuit 101 causes TVc <0.
It is determined whether or not is satisfied. The arithmetic circuit 101 is a TV
c <0 holds (control shutter speed is slower than 1 second)
In this case, an affirmative decision is made in step S111 and step S11
2 proceeds to step S1 when TVc <0 is not established.
A negative determination is made on 11 and the process proceeds to step S113. In step S112, the arithmetic operation circuit 101 sets the control shutter speed TVc to 0 and proceeds to step S115. As a result, the control shutter speed is the lower limit of the setting range 1
Set to seconds.

In step S107 to which the operation proceeds after making a negative decision in step S104 described above, the arithmetic operation circuit 101 makes A
It is determined whether Vc> 9 is established. Arithmetic circuit 101
When AVc> 9 is established (control aperture value is larger than F22), the affirmative decision is made in step S107 and the operation proceeds to step S108. When AVc> 9 is not established, a negative decision is made in step S107 and the operation proceeds to step S110. . In step S108, the arithmetic operation circuit 101 sets the control aperture value AVc to 9 and proceeds to step S109. As a result, the control aperture value is set to F22 which is the upper limit of the setting range. In step S109, the arithmetic circuit 1
01 calculates TVc = EV-9, and step S111
Go to. In step S110, the arithmetic circuit 101
Calculates TVc = EV / 2 + 1 and then executes step S111.
Go to.

In step S113 to which the operation proceeds after making a negative decision in step S111, the arithmetic operation circuit 101 makes T
It is determined whether Vc> 10 is established. Arithmetic circuit 10
1 satisfies TVc> 10 (control shutter speed is 1
/ 1000 seconds), an affirmative decision is made in step S113 and the operation proceeds to step S114, and if TVc> 10 is not established, a negative decision is made in step S113 and the operation proceeds to step S115. In step S114, the arithmetic operation circuit 101 sets the control shutter speed TVc to 10 and proceeds to step S115. As a result, the control shutter speed is set to 1/1000 seconds which is the upper limit of the setting range.

In step S115, the arithmetic circuit 10
1 determines whether or not the custom setting flag S = 1. The arithmetic operation circuit 101 makes an affirmative decision in step S115 if S = 1 (imaging sensitivity automatic change mode) to proceed to step S118 of FIG. 5, and if S = 0 (imaging sensitivity automatic change mode has been canceled), proceeds to step S115. Is negatively determined, and the process proceeds to step S116. In step S116,
The arithmetic circuit 101 sets the set image pickup sensitivity SVs to the control image pickup sensitivity SVc, and proceeds to step S117. In step S117, the arithmetic operation circuit 101 sets the flag C to 0, ends the processing in FIG.
Go to 4. Here, the flag C is 1 when the image pickup sensitivity is changed from the set image pickup sensitivity SVs (SVc ≠ SVs), and the flag C is not changed from the set image pickup sensitivity SVs (S
This is a flag for setting Vc = SVs) to 0.

In step S118 of FIG. 5, the arithmetic operation circuit 101 calculates the exposure deviation ΔEV by the following equation (2), and proceeds to step S119.

## EQU00002 ## .DELTA.EV = AVc + TVc-EV (2) where (AVc + TVc) is the control exposure and EV is the proper exposure.

In step S119, the arithmetic circuit 10
1 determines whether | ΔEV | <δ holds. δ
Is a predetermined value determined in advance, for example, 1 /
12 The arithmetic operation circuit 101 makes an affirmative decision in step S119 if | ΔEV | <δ is true to make a determination in step S119.
When it is determined that | ΔEV | <δ is not satisfied, the process proceeds to step 121, and a negative determination is made in step S119, and the process proceeds to step S120.
A positive determination in step S119 is a case where the control exposure can be regarded as a proper exposure, and a negative determination is a case where the control exposure is different from the proper exposure.

In step S120, the arithmetic circuit 10
1 calculates SVc = SVs + ΔEV and executes step S1.
Proceed to 21. As a result, the set imaging sensitivity is changed so that the proper exposure can be obtained. In step S121,
The arithmetic circuit 101 determines whether SVc> 9 holds. The arithmetic operation circuit 101 makes an affirmative decision in step S121 if SVc> 9 is satisfied (the control imaging sensitivity is higher than ISO1600 equivalent) to proceed to step S122, where S
When Vc> 9 is not established, a negative determination is made in step S121 and the process proceeds to step S123. In step S122, the arithmetic operation circuit 101 sets the control sensitivity SVc to 9 and proceeds to step S125. As a result, the control sensitivity is set to ISO 1600 which is the upper limit of the setting range.

In step S125, the arithmetic circuit 10
1 determines whether or not SVc = SVs is established. The arithmetic operation circuit 101 makes a negative decision in step S125 if SVc = SVs is not established to proceed to step S126, and if SVc = SVs is established in step S125.
Is affirmatively determined and the process proceeds to step S127. Step S1
In 26, the arithmetic operation circuit 101 sets 1 in the flag C, ends the processing in FIG. 4, and proceeds to step S4 in FIG. In step S127, the arithmetic operation circuit 101
The flag C is set to 0, the processing in FIG. 4 is terminated, and the process proceeds to step S4 in FIG.

In step S123, which proceeds after making a negative decision in step S121 described above, the arithmetic operation circuit 101 makes the S
When Vc <5 is satisfied (control imaging sensitivity is lower than ISO100 equivalent), an affirmative decision is made in step S123 and the operation proceeds to step S124, and when SVc <5 is not met, a negative decision is made in step S123 and the operation proceeds to step S125. In step S124, the arithmetic operation circuit 101 sets the control sensitivity SVc to 5 and proceeds to step S125. As a result, the IS whose control sensitivity is the lower limit of the setting range
It is set to the equivalent of O100.

In step S131 of FIG. 6, the arithmetic operation circuit 101 determines whether or not the mode parameter Mp = 2. The arithmetic operation circuit 101 makes an affirmative decision in step S131 if Mp = 2 (shutter speed priority auto exposure arithmetic mode) to proceed to step S132, whereas it makes a negative decision in step S131 if Mp ≠ 2 to make a negative decision in step S131 in FIG.
Go to.

In step S132, the arithmetic circuit 10
1 is set to control shutter speed TVc Shutter speed TV
s is set and the process proceeds to step S133. Here, the set shutter speed TVs is the shutter speed setting operation member 11
This is the shutter speed set by the operation # 1. In step S133, the arithmetic operation circuit 101 makes AVc =
EV-TVs is calculated and it progresses to step S134. However, AVc is a control aperture value. In step S134, the arithmetic operation circuit 101 determines whether AVc <3 is satisfied. The arithmetic operation circuit 101 performs step S when AVc <3 is satisfied (the control aperture value is smaller than F2.8).
Affirmative determination is made in step S134, and the flow advances to step S135 to set AVc
When <3 is not established, a negative decision is made in step S134 and the operation proceeds to step S136. In step S135, the arithmetic operation circuit 101 sets the control aperture value AVc to 3 and proceeds to step S138. As a result, the control aperture value is set to F2.8 which is the lower limit of the setting range.

In step S136, the arithmetic circuit 10
1 determines whether AVc> 9 holds. In the arithmetic circuit 101, AVc> 9 is satisfied (the control aperture value is F2.
If it is greater than 2), an affirmative decision is made in step S136 and the operation proceeds to step S137, and if AVc> 9 is not established, a negative decision is made in step S136 and the operation proceeds to step S138. In step S137, the arithmetic operation circuit 101
The control aperture value AVc is set to 9, and the process proceeds to step S138. As a result, the control aperture value is set to F22 which is the upper limit of the setting range.

In step S138, the arithmetic circuit 10
1 determines whether or not the custom setting flag S = 1. The arithmetic operation circuit 101 makes an affirmative decision in step S138 if S = 1 (imaging sensitivity automatic change mode) to proceed to step S118 in FIG. 5, and if S = 0 (imaging sensitivity automatic change mode has been canceled), proceeds to step S138. Is negatively determined, and the process proceeds to step S139. In step S139,
The arithmetic circuit 101 sets the set image pickup sensitivity SVs to the control image pickup sensitivity SVc, and proceeds to step S140. In step S140, the arithmetic operation circuit 101 sets the flag C to 0 and ends the processing in FIG.
Go to 4.

In step S141 of FIG. 7, the arithmetic operation circuit 101 determines whether or not the mode parameter Mp = 3. The arithmetic operation circuit 101 makes an affirmative decision in step S141 if Mp = 3 (aperture priority auto-exposure arithmetic mode) to proceed to step S142, and if Mp ≠ 3, in step S141.
The negative determination of 141 is performed, and the process proceeds to step S151 of FIG.

In step S142, the arithmetic circuit 10
In step 1, the control aperture value AVc is set to the set aperture value AVs, and the process proceeds to step S143. Here, the set aperture value AVs
Is an aperture value set by operating the aperture setting operation member 112. In step S143, the arithmetic operation circuit 101 calculates TVc = EV-AVs, and then in step S143.
Proceed to 144. However, TVc is a control shutter speed. In step S144, the arithmetic operation circuit 101 sets T
It is determined whether or not Vc <0 is established. Arithmetic circuit 101
Determines that TVc <0 is satisfied (control shutter speed is lower than 1 second), affirmative determination is made in step S144, and the process proceeds to step S145. move on.
In step S145, the arithmetic operation circuit 101 sets the control shutter speed TVc to 0 and proceeds to step S148. As a result, the control shutter speed is set to 1 second which is the lower limit of the setting range.

In step S146, the arithmetic circuit 10
1 determines whether TVc> 10 holds. The arithmetic operation circuit 101 performs step S14 when TVc> 10 is satisfied (control shutter speed is higher than 1/1000 second).
In the affirmative judgment of 6, the process proceeds to step S147, and TVc> 1.
If 0 is not established, a negative decision is made in step S146 and the operation proceeds to step S148. In step S147,
The arithmetic operation circuit 101 sets the control shutter speed TVc to 10 and proceeds to step S148. As a result, the control shutter speed is set to 1/1000 seconds which is the upper limit of the setting range.

In step S148, the arithmetic circuit 10
1 determines whether or not the custom setting flag S = 1. The arithmetic operation circuit 101 makes an affirmative decision in step S148 if S = 1 (imaging sensitivity automatic change mode) to proceed to step S118 in FIG. 5, and if S = 0 (imaging sensitivity automatic change mode has been canceled), proceeds to step S148. Is negatively determined, and the process proceeds to step S149. In step S149,
The arithmetic circuit 101 sets the set image pickup sensitivity SVs to the control image pickup sensitivity SVc, and proceeds to step S150. In step S150, the arithmetic operation circuit 101 sets the flag C to 0 and terminates the processing shown in FIG.
Go to 4.

The case of proceeding to step S151 in FIG. 8 is the case of the manual exposure calculation mode. Step S15
1, the arithmetic circuit 101 controls the control shutter speed TV.
Set shutter speed TVs to c and set step S1
Proceed to 52. Here, the set shutter speed TVs is the shutter speed set by the operation of the shutter speed setting operation member 111. In step S152, the arithmetic operation circuit 101 sets the control aperture value AVc to the set aperture value AVs.
Is set and the process proceeds to step S153. Here, the set aperture value AVs is the aperture value set by the operation of the aperture setting operation member 112.

In step S153, the arithmetic circuit 10
1 determines whether or not the custom setting flag S = 1. The arithmetic operation circuit 101 makes an affirmative decision in step S153 if S = 1 (imaging sensitivity automatic change mode) to proceed to step S118 in FIG. 5, and if S = 0 (imaging sensitivity automatic change mode has been canceled), proceeds to step S153. Is negatively determined, and the process proceeds to step S154. In step S154,
The arithmetic operation circuit 101 sets the set image pickup sensitivity SVs to the control image pickup sensitivity SVc, and proceeds to step S155. In step S155, the arithmetic operation circuit 101 sets 0 in the flag C and ends the processing in FIG.
Go to 4.

Details of the display process will be described with reference to the flowchart of FIG. In step S201 of FIG. 9, the arithmetic operation circuit 101 controls the control shutter speed TVc,
The display device 11 displays the control aperture value AVc and the set imaging sensitivity SVs.
5 is lit up and displayed, and the process proceeds to step S202.
Here, the display device 115 displays the shutter speed value, the F value, and the ISO equivalent value corresponding to each apex value. In step S202, the arithmetic circuit 101
Determines whether or not the custom setting flag S = 1. The arithmetic operation circuit 101 makes an affirmative decision in step S202 if S = 1 (imaging sensitivity automatic change mode) to proceed to step S203, and makes a negative decision in step S202 if S = 0 (imaging sensitivity automatic change mode is canceled). Then, the process proceeds to step S204.

In step S203, the arithmetic circuit 10
1 causes the display device 115 to blink a character (any one of P, S, A, and M) or mark indicating the exposure calculation mode corresponding to the value of the mode parameter Mp, and the processing in FIG. To step S5. Step S2
In 04, the arithmetic operation circuit 101 determines that the mode parameter M
Characters (P, S,
Either A or M) or the mark is lit up on the display device 115, the process of FIG. 9 is terminated, and the process proceeds to step S5 of FIG.

The details of the setting process will be described with reference to FIGS.
This will be described with reference to the flowchart in FIG. In step S301 of FIG. 10, the arithmetic operation circuit 101 determines whether or not a custom setting operation has been performed. Arithmetic circuit 1
If the operation signal is input from the custom setting operation member 113, the affirmative determination is made in step S301, and the flow proceeds to step S302. If the operation signal is not input from the custom setting operation member 113, 01 is determined in the negative and the step S301 is performed. Proceed to S305.

In step S302, the arithmetic circuit 10
1 determines whether or not the custom setting flag S = 0. The arithmetic operation circuit 101 makes an affirmative decision in step S302 if S = 0 (the imaging sensitivity automatic changing mode has been canceled) to proceed to step S303, where S = 1 (the imaging sensitivity automatic changing mode has been set). In case of step S
A negative determination is made in step 302, and the flow advances to step S304. In step S303, the arithmetic operation circuit 101 sets the flag S to 1
Is set (set to the imaging sensitivity automatic change mode), and FIG.
2 is completed and the process proceeds to step S6 in FIG. In step S304, the arithmetic operation circuit 101 sets the flag S to 0 (releases the imaging sensitivity automatic change mode), and
The process of 0 is terminated, and the process proceeds to step S6 of FIG.

In step S305, the arithmetic circuit 10
1 determines whether or not an operation of changing the imaging sensitivity is performed. The arithmetic operation circuit 101 makes an affirmative decision in step S305 if an operation signal has been input from the sensitivity setting operation member 109 to proceed to step S306, in which the sensitivity setting operation member 109 is entered.
When the operation signal is not input from step S305, a negative determination is made in step S305 and the process proceeds to step S321 in FIG. In step S306, the arithmetic operation circuit 101 determines whether the sensitivity is increased. The arithmetic operation circuit 101 makes an affirmative decision in step S306 if the operation signal from the sensitivity setting operation member 109 indicates an increase in sensitivity and proceeds to step S307, and makes a negative decision in step S306 if the operation signal does not instruct an increase in sensitivity. And proceeds to step S309.

In step S307, the arithmetic circuit 10
1 determines whether or not SVs = 9. Arithmetic circuit 101
Is SVs = 9 (setting imaging sensitivity is equivalent to ISO1600)
In this case, an affirmative decision is made in step S307, the processing in FIG. 10 is terminated, and the operation proceeds to step S6 in FIG. In this case, since the sensitivity setting range is the upper limit, the setting process is terminated without increasing the sensitivity. On the other hand, the arithmetic circuit 101 has SVs ≠ 9.
In the case of step S307, a negative determination is made, and step S3
Go to 08. In step S308, the arithmetic circuit 10
In No. 1, 1 is added to the set image pickup sensitivity SVs, the processing in FIG. 10 is ended, and the process proceeds to step S6 in FIG. As a result, the set image pickup sensitivity is increased by one step.

In step S309, the arithmetic circuit 10
1 determines whether the sensitivity is down. Arithmetic circuit 101
When the operation signal from the sensitivity setting operation member 109 indicates the sensitivity reduction, the affirmative decision is made in step S309 and the operation proceeds to step S310. The arithmetic operation circuit 101 makes a negative decision in step S309 if the operation signal does not instruct to decrease the sensitivity, ends the processing in FIG.
Go to 6.

In step S310, the arithmetic circuit 10
1 determines whether or not SVs = 5. Arithmetic circuit 101
When SVs = 5 (the set imaging sensitivity is equivalent to ISO100), the affirmative decision is made in step S310, the processing shown in FIG. 10 is ended, and the process proceeds to step S6 in FIG. in this case,
Since it is the lower limit of the sensitivity setting range, the setting process is terminated without lowering the sensitivity. On the other hand, the arithmetic operation circuit 101 makes a negative determination in step S310 if SVs ≠ 5, and then returns to step S311.
Go to. In step S311, the arithmetic circuit 101
Ends the process according to FIG. 10 by subtracting 1 from the set imaging sensitivity SVs, and proceeds to step S6 in FIG. As a result, the set image pickup sensitivity is lowered by one step.

In step S321 of FIG. 11, the arithmetic operation circuit 101 determines whether or not an exposure operation mode setting operation has been performed. The arithmetic operation circuit 101 makes an affirmative decision in step S321 if an operation signal has been input from the exposure mode setting operation member 110 to proceed to step S322, whereas it has a negative result in step S321 if no operation signal has been input from the exposure mode setting operation member 110. The determination is made and the process proceeds to step S331 in FIG.

In step S322, the arithmetic circuit 10
1 determines whether or not the program auto exposure calculation mode (P). The arithmetic operation circuit 101 makes an affirmative decision in step S322 if the operation signal from the exposure mode setting operation member 110 indicates the P mode to proceed to step S323, and if the operation signal does not indicate the P mode in step S323.
A negative determination is made in step 322, and the flow advances to step S324. In step S323, the arithmetic operation circuit 101 sets the mode parameter Mp to 1 (sets the program auto exposure arithmetic operation mode), ends the processing in FIG. 11, and proceeds to step S6 in FIG.

In step S324, the arithmetic circuit 10
1 determines whether or not the shutter speed priority auto exposure calculation mode (S). The arithmetic operation circuit 101 makes an affirmative decision in step S324 to give an affirmative decision in step S324 if the operation signal from the exposure mode setting operation member 110 indicates the S mode.
If the operation signal does not indicate the S mode, the process makes a negative decision in step S324 to proceed to step S326. In step S325, the arithmetic operation circuit 101 sets the mode parameter Mp to 2 (sets the shutter speed priority auto exposure arithmetic operation mode), and terminates the processing shown in FIG.
Proceed to step S6 in FIG.

In step S326, the arithmetic circuit 10
1 determines whether or not the aperture-priority automatic exposure calculation mode (A). The arithmetic operation circuit 101 makes an affirmative decision in step S326 if the operation signal from the exposure mode setting operation member 110 indicates the A mode to proceed to step S327,
If the operation signal does not indicate the A mode, step S32
A negative decision is made in step S6 and the operation proceeds to step S328. Step S
In 327, the arithmetic operation circuit 101 sets 3 to the mode parameter Mp (sets the aperture priority auto exposure calculation mode), ends the processing in FIG. 11, and proceeds to step S in FIG.
Go to 6.

In step S328, the arithmetic operation circuit 10
1 determines whether the mode is the manual exposure calculation mode (M). The arithmetic circuit 101 includes an exposure mode setting operation member 11
When the operation signal from 0 indicates the M mode, an affirmative decision is made in step S328 and the operation proceeds to step S329. When the operation signal does not instruct the M mode, a negative decision is made in step S328 and the processing shown in FIG. Proceed to step S6 in FIG. In step S329, the arithmetic circuit 1
In 01, the mode parameter Mp is set to 4 (set to the manual exposure calculation mode), the processing in FIG. 11 is terminated, and the process proceeds to step S6 in FIG.

In step S331 of FIG. 12, the arithmetic operation circuit 101 determines whether or not the mode parameter Mp is 1. The arithmetic operation circuit 101 makes an affirmative decision in step S331 if Mp = 1 (program auto exposure operation mode), ends the processing in FIG. 12, and proceeds to step S6 in FIG. As a result, in the program automatic exposure calculation mode, setting of the shutter speed and the aperture value by the operation member is prohibited. On the other hand, the arithmetic operation circuit 101 makes a negative determination in step S331 if Mp ≠ 1 (not in the program auto exposure arithmetic mode), and proceeds to step S332.

In step S332, the arithmetic operation circuit 10
1 determines whether the mode parameter Mp is 3 or not. The arithmetic operation circuit 101 makes an affirmative decision in step S332 if Mp = 3 (aperture priority auto-exposure arithmetic mode), and the operation proceeds to step S341. As a result, in the aperture priority auto exposure calculation mode, setting of the shutter speed by the operation member is prohibited. On the other hand, if Mp ≠ 3 (not in the aperture priority auto exposure calculation mode), the calculation circuit 101 performs step S
The negative determination of 332 is performed, and the process proceeds to step S333. As a result, in the shutter speed priority automatic exposure calculation mode, setting of the aperture value by the operation member is prohibited.

In step S333, the arithmetic circuit 10
1 determines whether or not a shutter speed changing operation has been performed. The arithmetic circuit 101 includes the shutter speed setting operation member 1
When an operation signal is input from 11, step S333
Is affirmatively determined, the process proceeds to step S334, and when an operation signal is not input from the shutter speed setting operation member 111, a negative determination is made in step S333 and the process proceeds to step S340.

In step S334, the arithmetic operation circuit 10
1 determines whether or not the speed-up is set. Arithmetic circuit 101
If the operation signal from the shutter speed setting operation member 111 indicates a higher speed, the affirmative decision is made in step S334 and the operation proceeds to a step S335. If the operation signal does not instruct the higher speed, a negative decision is made in the step S334 and a step is executed. S
Proceed to 337.

In step S335, the arithmetic operation circuit 10
1 determines whether TVs = 10. Arithmetic circuit 101
Is TVs = 10 (set shutter speed is 1/1000.
In the case of second), an affirmative decision is made in step S335, the processing in FIG. 12 is terminated, and the operation proceeds to step S6 in FIG. In this case, since the shutter speed setting range is the upper limit, the setting process is terminated without increasing the speed. On the other hand, the arithmetic circuit 101 is a TV
When s ≠ 10, a negative determination is made in step S335, and the process proceeds to step S336. In step S336, the arithmetic operation circuit 101 adds 1 to the set shutter speed TVs, ends the processing in FIG. 12, and proceeds to step S6 in FIG. As a result, the set shutter speed is increased by one step.

In step S337, the arithmetic circuit 10
1 determines whether or not the speed is reduced. The arithmetic circuit 101 is
When the operation signal from the shutter speed setting operation member 111 instructs the speed reduction, the affirmative decision is made in step S337 and the operation proceeds to step S338. The arithmetic operation circuit 101 makes a negative decision in step S337 if the operation signal does not instruct the speed reduction, ends the processing in FIG. 12, and proceeds to step S6 in FIG.

In step S338, the arithmetic operation circuit 10
1 determines whether TVs = 0. Arithmetic circuit 101
When TVs = 0 (set shutter speed is 1 second), an affirmative decision is made in step S338, the processing in FIG. 12 is terminated, and the routine proceeds to step S6 in FIG. In this case, since the shutter speed setting range is the lower limit, the setting process is terminated without lowering the speed. On the other hand, the arithmetic operation circuit 101 makes a negative decision in step S338 if TVs ≠ 0 to proceed to step S339. In step S339, the arithmetic operation circuit 101 subtracts 1 from the set shutter speed TVs, ends the processing in FIG. 12, and proceeds to step S6 in FIG. This allows
The set shutter speed becomes one step slower.

In step S340 to which the operation proceeds after making a negative decision in step S333, the arithmetic operation circuit 101 makes a decision as to whether the mode parameter Mp is 4 or not. Arithmetic circuit 1
In the case of Mp = 4 (manual exposure calculation mode), 01 makes an affirmative decision in step S340, and proceeds to step S341. On the other hand, when Mp ≠ 4 (not in the manual exposure calculation mode), the arithmetic operation circuit 101 makes a negative decision in step S340, ends the processing in FIG. 12, and proceeds to step S6 in FIG.

In step S341, it is determined whether or not the aperture value changing operation has been performed. The arithmetic circuit 101 is
When an operation signal is input from the aperture setting operation member 112, an affirmative decision is made in step S341 and the operation proceeds to step S342, and when an operation signal is not input from the aperture setting operation member 112, a negative decision is made in step S341 and the processing shown in FIG. Ends and the process proceeds to step S6 in FIG.

In step S342, the arithmetic circuit 10
1 determines whether or not the aperture diameter is set to be small. The arithmetic operation circuit 101 makes an affirmative decision in step S342 if the operation signal from the aperture setting operation member 112 indicates the direction of narrowing down and proceeds to step S343, and makes a negative decision in step S342 if the operation signal is not in the direction of narrowing down. Proceed to S345.

In step S343, the arithmetic circuit 10
1 determines whether AVs = 9. Arithmetic circuit 101
When AVs = 9 (set aperture value is F22), affirmative determination is made in step S343, the processing in FIG.
Proceed to step S6 in FIG. In this case, since the upper limit of the aperture value setting range is set, the setting process ends without further narrowing down. On the other hand, the arithmetic operation circuit 101 makes a negative decision in step S343 if AVs ≠ 9 to proceed to step S344. In step S344, the arithmetic operation circuit 101 adds 1 to the set aperture value AVs, ends the processing in FIG. 12, and proceeds to step S6 in FIG. As a result, the set aperture value increases by one step.

In step S345, the arithmetic operation circuit 10
1 determines whether or not the aperture diameter is set to be large. When the operation signal from the aperture setting operation member 112 indicates the direction to open the aperture, the arithmetic circuit 101 performs step S3.
An affirmative decision is made in step S45, and the operation proceeds to step S346. The arithmetic operation circuit 101 makes a negative decision in step S345 if the operation signal does not indicate a direction to open the aperture, ends the processing in FIG. 12, and proceeds to step S6 in FIG.

In step S346, the arithmetic circuit 10
1 determines whether AVs = 3. Arithmetic circuit 101
When AVs = 3 (set aperture value is F2.8), affirmative determination is made in step S346, the processing in FIG. 12 is terminated, and the flow proceeds to step S6 in FIG. In this case, since it is the lower limit of the aperture value setting range, the setting process is terminated without further opening. On the other hand, the arithmetic operation circuit 101 makes a negative decision in step S346 if AVs ≠ 3 to proceed to step S347. In step S347, the arithmetic operation circuit 101 subtracts 1 from the set aperture value AVs, ends the processing in FIG. 12, and proceeds to step S6 in FIG. This reduces the set aperture value by one step.

According to the embodiment described above, the following operational effects can be obtained. (1) When the electronic camera is set to the program automatic exposure calculation mode (P) and the imaging sensitivity automatic change mode is set (S = 1), the control exposure (AVc + TVc) calculated by the program automatic exposure calculation is set. When the exposure deviation ΔEV from the proper exposure EV is a predetermined value δ or more,
The set imaging sensitivity SVs is automatically changed according to the exposure deviation ΔEV. Therefore, the set imaging sensitivity SVs
Is changed only after the set shutter speed TVs and the set aperture value AVs are changed only when the proper exposure is not obtained. Therefore, the intention of the photographer is higher than that when the set imaging sensitivity SVs is changed first. The S / N ratio of the image, which is contrary to the above, does not easily deteriorate. (2) When the electronic camera is set to the shutter speed priority automatic exposure calculation mode (S) and is set to the imaging sensitivity automatic change mode (S = 1), the control exposure calculated by the shutter speed priority automatic exposure calculation (AVc + TVs)
When the exposure deviation ΔEV between the optimum exposure EV and the proper exposure EV is a predetermined value δ or more, the set imaging sensitivity SVs according to the exposure deviation ΔEV.
Was changed automatically. Therefore, the set image pickup sensitivity SVs is changed after the set aperture value AVs is changed only when the proper exposure is not obtained, so that the change of the set image pickup sensitivity SVs is performed before the change of the photographer. Degradation of the S / N ratio of an image against the intention is unlikely to occur. (3) When the electronic camera is set to the aperture value priority automatic exposure calculation mode (A) and the imaging sensitivity automatic change mode is set (S = 1), the control exposure calculated by the aperture value priority automatic exposure calculation When the exposure deviation ΔEV between (AVs + TVc) and the proper exposure EV is equal to or larger than the predetermined value δ,
The set imaging sensitivity SVs is automatically changed according to the exposure deviation ΔEV. Therefore, the set imaging sensitivity SVs
The change of S is performed only after the set shutter speed TVs is changed only when the proper exposure is not obtained. Therefore, compared to the case where the set imaging sensitivity SVs is changed first, the S The deterioration of the / N ratio hardly occurs. (4) When the electronic camera is set to the manual exposure calculation mode (M) and is set to the imaging sensitivity automatic change mode (S = 1), the control exposure (AVs + TVs) calculated by the manual exposure calculation and the proper exposure are calculated. If the exposure deviation ΔEV from the EV is a predetermined value δ or more, the exposure deviation ΔEV
The set imaging sensitivity SVs is automatically changed according to the above. Therefore, since the setting imaging sensitivity SVs is changed only when proper exposure cannot be obtained, deterioration of the S / N ratio of an image against the photographer's intention is unlikely to occur. (5) The display indicating the exposure calculation mode displayed on the display device 115 corresponds to each of the exposure calculation modes 1 to 4 above.
Display either "P", "S", "A", or "M",
When the imaging sensitivity automatic change mode is set (S =
A blinking display is performed in 1) and a lighting display is performed when the imaging sensitivity automatic change mode is canceled (S = 0). Therefore, it is possible to display whether or not the imaging sensitivity automatic change mode is set in each exposure calculation mode without increasing the number of display segments of the display device 115, which increases the cost as compared with the case of increasing the display segments. Can be suppressed.

In the above description, only when the proper exposure cannot be obtained, the set image pickup sensitivity SV is set according to the exposure deviation ΔEV.
s is changed by setting aperture value AVs and setting shutter speed TVs
I changed it after the change. On the other hand, when the proper exposure cannot be obtained, the set aperture value AVs and the set imaging sensitivity SVs are changed in combination according to the exposure deviation ΔEV, or the set shutter speed TVs is set according to the exposure deviation ΔEV. May be combined with the change of the set imaging sensitivity SVs. Furthermore, when the proper exposure cannot be obtained, the change of the set aperture value AVs, the change of the set shutter speed TVs, and the change of the set image pickup sensitivity SVs may be performed in combination in accordance with the exposure deviation ΔEV. In this case, any one of the above and may be selectively switched.

Further, any one of the above and may be selectively switched.

Further, any one of the above and may be selectively switched.

Instead of displaying on the display device 115 whether or not the image pickup sensitivity automatic change mode is set in each exposure calculation mode, whether or not the set image pickup sensitivity is changed may be displayed. The flowchart of FIG. 13 describes the display processing in this case, and is used instead of the flowchart of FIG. 9 described above.

In step S210 of FIG. 13, the arithmetic operation circuit 101 causes the display device 115 to illuminate and display the control shutter speed TVc, the control aperture value AVc, and the set image pickup sensitivity SVs, and then the operation proceeds to step S211. Here, the display device 115 displays the shutter speed value, the F value, and the ISO equivalent value corresponding to each apex value. In step S211, the arithmetic operation circuit 101
It is determined whether the flag C = 1. The arithmetic circuit 101 is C
= 1 (control imaging sensitivity SVc ≠ set imaging sensitivity SVs), an affirmative decision is made in step S211 and step S212.
C = 0 (control imaging sensitivity SVc = set imaging sensitivity S
If it is Vs), a negative decision is made in step S211 and the operation proceeds to step S213.

In step S212, the arithmetic circuit 10
1 indicates that the letter (one of P, S, A, and M) or mark indicating the exposure calculation mode corresponding to the value of the mode parameter Mp is displayed blinking on the display device 115, and is replaced with the lighting display of the set imaging sensitivity SVs. Control imaging sensitivity SV
Flashes c. The arithmetic operation circuit 101 ends the process of FIG. 13 and proceeds to step S5 of FIG. On the other hand, in step S213, the arithmetic operation circuit 101 causes the display device 115 to illuminate and display a character (one of P, S, A, and M) or mark indicating the exposure operation mode corresponding to the value of the mode parameter Mp, and FIG. 2 is completed and the process proceeds to step S5 in FIG.

According to the display processing shown in FIG. 13, the display indicating the exposure calculation mode displayed on the display device 115 is the same as the above-mentioned 1
Corresponding to each exposure calculation mode of ~ 4 "P", "S",
When either "A" or "M" is displayed and the imaging sensitivity is automatically changed in the imaging sensitivity automatic changing mode (step S2
A blinking display is performed in 12) and a lighting display is performed when the imaging sensitivity is not automatically changed (step S213). When the imaging sensitivity is automatically changed, the changed control imaging sensitivity SVc is further displayed in blinking. Therefore, the display device 1
When the number of display segments is increased, it is possible to display whether or not the imaging sensitivity is automatically changed in each exposure calculation mode and to display the automatically changed imaging sensitivity without increasing the number of 15 display segments. It is possible to suppress the cost increase compared to.

In the above description, an example has been described in which different display modes are displayed, for example, by making the display unit light up or blink. Alternatively, when the display has segments that emit light in multiple colors, the display colors may be changed to different modes.

Furthermore, in the case of a display device capable of reversing display in which the background portion of the display segment is made to emit light, a different mode can be adopted in which normal display is performed using only the segment or reverse display is performed using the background portion. You may

Correspondence between each component in the claims and each component in the embodiment of the invention will be described. The image pickup device includes, for example, a CCD 102, a drive circuit 104, and an image pickup signal processing circuit 105. The brightness detection device is composed of, for example, the photometric device 116 and the arithmetic circuit 101. The exposure sensitivity corresponds to the imaging sensitivity. The exposure time corresponds to the shutter speed. The first arithmetic circuit, the second arithmetic circuit, the control circuit, and the display control circuit are configured by the arithmetic circuit 101, for example. The selection operation means is composed of, for example, the custom setting operation member 113. The control limit of the exposure time depends on the setting range of the shutter speed (for example, 1
~ 1/1000 second) corresponds. The control limit of the aperture value is
The setting range of the aperture value (for example, F2.8 to F22) corresponds. The exposure calculation mode display displays, for example, any of “P”, “S”, “A”, and “M” corresponding to each exposure calculation mode. The display mode corresponds to, for example, a lighting display and a blinking display. Note that each component is not limited to the above configuration as long as the characteristic function of the present invention is not impaired.

[0088]

According to the electronic camera of the present invention, the exposure sensitivity is changed when the result calculated by using the set exposure sensitivity is different from the proper exposure. The deterioration of the / N ratio is less likely to occur.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an electronic camera according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating a flow of camera operation processing performed by an arithmetic circuit.

FIG. 3 is a flowchart illustrating a flow of camera operation processing performed by an arithmetic circuit.

FIG. 4 is a flowchart illustrating a flow of exposure calculation processing performed by a calculation circuit.

FIG. 5 is a flowchart illustrating a flow of exposure calculation processing performed by a calculation circuit.

FIG. 6 is a flowchart illustrating a flow of exposure calculation processing performed by a calculation circuit.

FIG. 7 is a flowchart illustrating a flow of exposure calculation processing performed by a calculation circuit.

FIG. 8 is a flowchart illustrating a flow of exposure calculation processing performed by a calculation circuit.

FIG. 9 is a flowchart illustrating a flow of display processing performed by an arithmetic circuit.

FIG. 10 is a flowchart illustrating a flow of a setting process performed by an arithmetic circuit.

FIG. 11 is a flowchart illustrating a flow of a setting process performed by an arithmetic circuit.

FIG. 12 is a flowchart illustrating a flow of a setting process performed by an arithmetic circuit.

FIG. 13 is a flowchart illustrating a flow of a display process performed by an arithmetic circuit.

[Explanation of symbols]

101 ... Arithmetic circuit, 102 ... CC
D, 109 ... Sensitivity setting operation member, 110 ... Exposure mode setting operation member, 111 ... Shutter speed setting operation member, 112 ... Aperture setting operation member, 113 ... Custom setting operation member, 115 ... Display device,
116 ... Photometric device

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03B 17/18 G03B 17/18 A H04N 5/335 H04N 5/335 Q // H04N 101: 00 101: 00 F-term (reference) 2H002 AB01 AB03 CC00 CC01 CC21 CC31 FB06 FB11 FB23 FB24 FB25 FB28 FB56 FB71 JA07 2H102 AA52 AA66 BA03 BA05 BA12 BB03 BB05 BB08 BB23 BB26 C05 AC55 AC03 AC55 AC02 AC17 AC42 AC17 AC42 AC17 AC42 AC17 AC52 AC11 AC13 AC52 AC11 AC13 AC52 AC11 AC13 AC12 AC17 AC42 AC17 AC52 AC12 AC17 AC42 AC17 AC42 AC17 AC42 AC17 AC42 AC17 AC42 AC15 AC42 AC15 AC42 AC25 DX04 EX11 EX34

Claims (10)

[Claims] 1. An image pickup device for picking up a subject image through a taking lens, a luminance detection device for detecting subject luminance, an exposure sensitivity set for the image pickup device, an exposure time set for the image pickup device, Exposure calculation is performed using the aperture value set in the taking lens and the subject brightness detected by the brightness detection device, and at least one of the exposure time and the aperture value is changed to obtain the proper exposure. And a first arithmetic circuit for calculating the controlled exposure, and a first arithmetic circuit for changing the exposure sensitivity and performing further exposure arithmetic when the arithmetic result by the first arithmetic circuit is different from the proper exposure. An electronic camera, comprising: a control circuit for controlling. 2. The electronic camera according to claim 1, wherein the exposure sensitivity set in the image pickup device, the exposure time set in the image pickup device, the aperture value set in the taking lens, and An exposure calculation is performed using each of the subject brightnesses detected by the brightness detection device, and at least one of the exposure sensitivity, the exposure time, and the aperture value is changed to obtain a proper exposure, and a control exposure is calculated. The electronic camera further comprising: a second arithmetic circuit; and a selection operation means for selecting one of the first arithmetic circuit and the second arithmetic circuit. 3. The electronic camera according to claim 2, wherein the first arithmetic circuit and the second arithmetic circuit change the exposure time and the aperture value in a predetermined combination so as to obtain proper exposure. Set the program exposure calculation mode to calculate the control exposure, and the aperture value priority exposure calculation mode to calculate the control exposure by changing the exposure time so that the proper exposure can be obtained with the set aperture value. Exposure time priority exposure calculation mode that calculates the control exposure by changing the aperture value so that the proper exposure can be obtained with the specified exposure time, and manual exposure calculation mode that calculates the control exposure with the set exposure time and aperture value An electronic camera characterized by having and respectively. 4. The electronic camera according to claim 3, wherein the control circuit controls the exposure time when the first arithmetic circuit performs an exposure calculation in the program exposure calculation mode or the aperture value priority exposure mode. When the calculation result differs from the proper exposure according to, the first calculation circuit is controlled so that the exposure sensitivity is changed according to the deviation between the calculation result and the proper exposure to further perform the exposure calculation. camera. 5. The electronic camera according to claim 3, wherein when the first arithmetic circuit performs the exposure calculation in the exposure time priority exposure calculation mode, the control circuit gives a calculation result due to a control limit of an aperture value. An electronic camera, characterized in that when the exposure is different from the proper exposure, the exposure sensitivity is changed in accordance with a deviation between the calculation result and the proper exposure to further perform the exposure calculation. 6. The electronic camera according to claim 3, wherein when the first arithmetic circuit performs an exposure calculation in the manual exposure calculation mode, the control circuit calculates a calculation result when the calculation result is different from an appropriate exposure. The electronic camera is characterized in that the first arithmetic circuit is controlled so that the exposure sensitivity is changed in accordance with a deviation between the proper exposure and the exposure. 7. The electronic camera according to claim 3, wherein in any one of the program exposure calculation mode, the aperture value priority exposure calculation mode, the exposure time priority exposure calculation mode, and the manual exposure calculation mode. A display device that displays an exposure calculation mode indicating whether or not exposure calculation is performed, and a case where the first calculation circuit is selected by the selection operation means and a case where the second calculation circuit is selected. An electronic camera, further comprising: a display control device that controls the display device to change a mode of the exposure calculation mode display. 8. The electronic camera according to claim 7, wherein the display control device displays blinking when the first arithmetic circuit is selected and when the second arithmetic circuit is selected. An electronic camera, characterized in that the display device is controlled so as to perform a lighting display. 9. The electronic camera according to claim 3, wherein any one of the program exposure calculation mode, the aperture value priority exposure calculation mode, the exposure time priority exposure calculation mode, and the manual exposure calculation mode is selected. A display device for displaying an exposure calculation mode indicating whether or not the exposure calculation is performed, and a mode of the exposure calculation mode display depending on whether the exposure sensitivity is changed by the first calculation circuit or not. An electronic camera, further comprising: a display control device that controls the display device to change. 10. The electronic camera according to claim 9, wherein the display control device performs a blinking display when the exposure sensitivity is changed and a lighting display when the exposure sensitivity is not changed. An electronic camera that controls the display device.