JP2969824B2 - camera - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a camera, and is put into practical use as a camera having an automatic exposure correction function.

[Prior Art] Conventionally, a camera having an automatic exposure control function of dividing a shooting screen into a plurality of photometric areas and determining an appropriate exposure value by a predetermined algorithm based on a plurality of photometric values obtained for each photometric area. Are commercially available. However, depending on the photographer, there is a case where it is desired to provide an exposure slightly over or slightly under the exposure value determined by the camera. In order to cope with such a case, an exposure correction function is provided that enables the exposure value determined by the camera to be corrected by manual operation.

[Problems to be Solved by the Invention] However, it is troublesome to perform an exposure correction operation every time shooting is performed. If it is omitted, there is a problem that the finish feeling intended by the photographer cannot be obtained. Therefore, it is conceivable to make the camera learn the tendency of the past exposure correction and automatically perform the exposure correction based on the learning result. The correction value to be learned is mainly the manually set override amount, but it is also necessary to learn the AE-locked spot metering value. This is because the fact that the photographer selects the spot metering mode and locks the AE for a certain scene means that the automatic exposure value determined by the camera is not suitable for the scene. In such a case, if the photographer wishes, the brightness difference between the proper exposure value based on the AE-locked spot metering value and the automatic exposure value determined by the camera is used for the exposure compensation for the scene. It is considered necessary to learn as a value.

The present invention has been made in view of such a point,
An object of the present invention is to provide a camera capable of learning a difference between an appropriate exposure value based on a spot photometry value locked by the photographer and an automatic exposure value determined by the camera.

[Means for Solving the Problems] In the camera according to the present invention, in order to solve the above-described problems, as shown in FIG. Spot metering means 1 for outputting BV _SP , multi-segment metering means 2 for metering a plurality of areas of the shooting screen to output multi-segment metering value BV1, and multi-segment metering obtained by multi-segment metering means 2. a photometric value correcting means 3 for determining the automatic photometric value BV2 by adding the correction value ΔBVc the value BV1, exposure calculation means for calculating an exposure value EV for use in control based on automatic photometric value BV2 or spot light measurement value BV _SP 4
Selecting means 5 for selecting whether to use the automatic photometric value BV2 or the spot photometric value BV _SP for the calculation of the exposure value EV, an AE lock operation means 6 which is manually operated, and a spot for calculating the exposure value EV. a correction value storage means 7 for storing after exposure completion if the operation of the AE lock operation means 6 is a brightness difference between the spot photometric value BV _SP and the automatic photometric value BV2 as a correction value BV5 when using a light measurement value BV _SP, Correction value predicting means 8 for predicting the correction value ΔBVc to be added to the multi-segment photometric value BV1 by the photometric value correcting means 3 based on the stored contents of the correction value storing means 7 in a direction in which the automatic photometric value BV2 becomes an appropriate value. It is characterized by having.

However, FIG. 1 is an explanatory diagram showing the present invention in a functionally-blocked manner. In the embodiments described later, all or a part of the units 1 to 8 are realized by a program of a microcomputer. The spot photometer 1 is in # 20 and # 22, the multi-segment photometer 2 is in # 45, the photometer correction means 3 is in # 60,
Exposure calculation means 4 is # 165, and selection means 5 is # 65- # 75.
The AE lock operation means 6 is in # 80 to # 100, the correction value storage means 7 is in # 102, # 191 to # 195, and the correction value prediction means 8 is in ##.
50 and # 55 respectively.

[Operation] Hereinafter, the operation of the present invention will be described with reference to FIG.

Spot metering means 1 outputs a spot metering value BV _SP and metering a small area in the center of the shooting screen. Further, the multi-segment metering means 2 measures the light in a plurality of areas of the photographing screen, and outputs a multi-segment metering value BV1 by a predetermined algorithm based on the metering value in each area. The photometric value correcting means 3 calculates an automatic photometric value BV2 by adding the correction value ΔBVc to the multi-segment photometric value BV1. The exposure calculation unit 4 calculates an exposure value EV for use in control based on automatic photometric value BV2 or spot light measurement value BV _SP. Automatic metering value BV for calculation of exposure value EV
Whether to use 2 or to use the spot photometric value BV _SP can be selected by the selection means 5. Normally, the automatic photometric value BV2 is selected, and exposure is performed using the exposure value EV determined by the camera based on the automatic photometric value BV2. If the automatic photometric value BV2 is inappropriate, the spot photometric value BV _SP is selected, the spot photometric value BV _SP is AE-locked by the AE lock operating means 6, and the spot photometric value BV _SP is determined based on the spot photometric value BV _SP. Exposure is performed using the exposure value EV determined by the camera. In this case, the luminance difference between the automatic photometric value BV2 spot photometric value BV _SP and the camera has been determined is stored in the correction value storage means 7 as a correction value BV5. After that, the correction value prediction means 8 predicts the correction value ΔBVc based on the stored contents of the correction value storage means 7. This correction value is added to the multi-segment photometry value BV1 by the photometry value correction means 3 so that the subsequent automatic photometry value BV2 is corrected so as to give an appropriate exposure.

Embodiment FIG. 2 shows a circuit configuration of a camera as one embodiment of the present invention. In the figure, μC denotes a microcomputer (hereinafter referred to as “microcomputer”), which performs exposure calculation and exposure control, and sequence control of the entire camera. Microcomputer μ
C is connected to various peripheral circuits, and can exchange information with these peripheral circuits.

LMC is a photometric circuit that performs TTL photometry, and its photometric range is divided into two areas, a central part SP of the photographing screen and an entire screen AM excluding the central part of the photographing screen, as shown in FIG. The area ratio of the two regions is set to 1: 8. Light measuring circuit LMC, the peripheral photometry to seek and spot metering function of finding a spot photometric value BV _SP and photometry of the central part SP of the shooting screen, the peripheral photometric value BV _AM and photometry of the entire screen AM except for the central part of the shooting screen Has a function. The information of the spot metering value BV _SP and the peripheral metering value BV _AM is transmitted to the icon μC after being exchanged into digital quantities.

The DSP is a display circuit that receives display data from the microcomputer μC and performs necessary display in the finder. The display contents will be described later.

DDR is an exposure control circuit that controls the aperture and shutter based on the aperture value and shutter speed calculated by the microcomputer μC, and also controls film winding.

The LEC is a lens circuit built in the taking lens, and transmits lens data unique to the taking lens to the camera body. As the contents of the lens data, for example, the open aperture value AV
o, focal length f, distance data Dv, and the like.

ISO is a film sensitivity reading circuit which reads film sensitivity information recorded in a film cartridge or a semiconductor memory mounted on the cartridge, and transmits the information to the microcomputer μC. This information is used for the AE calculation in the microcomputer μC. The circuit ISO may be provided with a manual operation member (push button, dial, etc.) so that the film sensitivity can be set and changed manually.

Each of the input ports P0 to P10 of the microcomputer μC is pulled up to “High” level by a resistor (not shown), and is connected to the ground level via another switch. When one of the switches is turned on, the corresponding input port goes to the “Low” level, and the ON / OFF of each switch can be determined by the microcomputer μC. Hereinafter, each switch will be described.

S1 is a shooting preparation switch which is turned on when a first stroke of a release button (not shown) is pressed down. When this switch is turned on, each operation of photometry and exposure calculation is started.

S _AEL is a status switch (AE lock switch) for performing AE lock, and AE lock is performed only when this switch is ON.

_SQ is a learning mode switch, which is a normally open switch, which is operated so that the camera can feed back the exposure correction value at that time to the exposure value determined independently by the camera at the next exposure.

Srf is a status switch (photometric reference selection switch) for selecting whether the reference value of the photometric display is an average photometric value or a spot photometric value. When this switch is ON, the average photometric value is selected. When OFF, the spot metering value is selected.

S2 is ON by pressing down the second stroke of the release button
When the switch is turned on, an exposure control operation is started.

Sup is an up switch, Sdn is a down switch,
Both are normally open switches, and serve as an up / down switch for setting an override amount when a switch Sov described later is ON.

S _SP is a status switch (spot metering switch) operated to perform spot metering.
When set to ON, the spot metering mode is set; when set to OFF, the mode switches to automatic metering mode. In automatic metering mode, the reference metering value
BVrf, magnification β, peripheral photometric value BV _AM , spot photometric value
The scene of the subject is determined from the BV _SP, and the exposure value is automatically corrected based on the past tendency of exposure correction for each scene.

Sov is an override switch for manually performing exposure compensation.
When the down switches Sup and Sdn are operated, the override amount is up / down operated. This switch Sov
Is OFF, the up / down switches Sup, Sdn
Can be used to up / down other amounts, but is not relevant to the present invention, and its description is omitted.

_SM is a main switch. When the switch _SM is ON, the camera can operate, and when OFF, the camera cannot operate.

Of the above switch, the main switch S _M is either or OFF is turned ON, the signal changes to "Low" level from "High" level from the pulse generator PG is inputted to the interrupt input terminal INT1, the microcomputer μC Executes the SMINT flow shown in FIG. In # 1, the state of the input port P9 is detected, and it is determined whether the main switch _SM is ON or OFF. If the main switch S _M is OFF, the microcomputer μC stops. Also,
If the main switch S _M is ON, the flag of the microcomputer μC in # 2, registers, etc. are all reset, for example, is reset here also exposure correction value BV4 below. However, the E ² PROM described later is not reset. When the reset process of # 2 is completed, the microcomputer μC stops.

Of the above switches, one of the shooting preparation switch S1, the AE lock switch S _AEL and the learning mode switch S _Q is turned on.
The output of the AND circuit AN changes from “High” level to “L”.
ow "level, this signal is input to the interrupt input terminal INT2, and the microcomputer μC executes the flow of S1INT shown in Fig. 5. First, the flag AELF indicating AE lock is reset (# 5). Next, the lens data unique to the photographing lens is read from the lens circuit LEC (# 10), and includes at least the open aperture value AVo, the focal length f, and the distance data Dv. The photographing magnification β is calculated from f and the distance data Dv (# 1
Five). Next, the spot metering value BV _SP and the peripheral metering value BV _AM are input from the metering circuit LMC, and the aperture value is set to each metering value.
Add AVo (# 20, # 22). Then, a switch Srf is used to determine whether the reference metering value is a spot metering value or an average metering value.
To obtain the spot metering value, the spot metering value BV _SP is substituted for the reference metering value BVrf if the metering value is used as the spot metering value, and the average metering value BV _AV = (BV
_SP + 8BV _AM) / 9 to assign a (# 25 to # 35). Next, a difference (BV _AM −BV _SP ) between the peripheral photometric value BV _AM and the spot photometric value BV _SP is obtained, and is set as a luminance difference ΔBV (# 40). And the photographing magnification β
From the spot photometric value BV _SP and the peripheral photometric value BV _AM , a multi-segment photometric value BV1 is obtained by the following equation (# 45).

BV1 = in _{kBV SP + (1-k)} BV AM the above equation, the coefficient k (<1) the spot photometric value BV _SP
And the peripheral photometric value BV _AM.
Are set as follows in consideration of the size of the main subject estimated from

If β ≧ 1/10, it is considered that the main subject occupies the entire screen, and k = 0.5 in order to perform center-weighted photometry.

If 1/10> β ≧ 1/40, it is assumed that the main subject is slightly smaller than the above and the ratio of the portion included in the center to the portion included in the peripheral region is larger, and k = 0.6.

If 1/40> β ≧ 1/100, it is considered that the main subject is smaller and the ratio included in the center is larger, and k = 0.8
And

If 1/100> β ≧ 1/150, the main subject becomes even smaller, but it does not always enter the central spot metering area, and k = 0.
And 4.

If 1/150> β, it is considered that the possibility of landscape photography is high, and k is set to 0.2 in order to perform average photometry.

Next, the reference photometric value BVrf, the photographing magnification β, and the luminance difference ΔBV
, The N exposure correction values ΔBVci stored for the scene are read out (# 5).
0). That is, for one combination of the reference photometric value BVrf, the imaging magnification β, and the luminance difference ΔBV, one scene c
(BVrf, β, ΔBV) is determined, and each scene c
N exposure correction values ΔBVci (i = 1,..., N) are stored for (BVrf, β, ΔBV). This exposure correction value ΔBVci is stored in the E ² PROM incorporated in the microcomputer [mu] C (or E ² PROM incorporated in the IC card that is attached to the camera), erased OFF the main switch S _M of the camera Not done. In # 55, an average of N exposure correction values ΔBVci (i = 1,..., N) read from the E ₂ PROM is obtained, and this is set as a correction value ΔBVc learned for the scene.
Then, the correction value ΔBVc is added to the photometric value BV1 to obtain an automatic photometric value BV2 (# 60). The automatic photometric value BV2 is a photometric value that reflects the learning result of the scene of the subject at that time and is predicted to give an appropriate exposure for that scene.

Here, the scene of the subject will be described. The camera of the present invention learns the tendency of the past exposure correction, predicts the exposure correction value ΔBVc desired by the photographer, adds the predicted exposure correction value ΔBVc to the photometric value BV1, and sets the proper exposure. Although the photometric value BV2 automatically corrected to be given is obtained, the exposure correction value ΔBVc differs depending on the scene of the subject. For example, it is conceivable that the direction of exposure correction is reversed between a forward light scene and a backlight scene. Therefore, a forward light scene and a back light scene are discriminated using the brightness difference ΔBV between the spot photometric value BV _SP and the peripheral photometric value BV _AM . In addition, it is considered that the tendency of the exposure correction is different in a landscape scene, a person scene, and a close-up scene. Therefore, these scenes are determined using the photographing magnification β. Further, it is considered that the exposure correction tendency is different between a high-brightness snowy mountain shooting scene and a low-brightness nighttime shooting scene. Therefore, the reference metering value BV
A high-luminance scene and a low-luminance scene are distinguished using rf. Note that a more complicated scene of a subject can be determined by dividing the shooting screen into a plurality of regions and combining the subject distance information and the subject luminance information obtained for each region.

Next, it is determined whether the spot metering switch _SSP is ON or OFF (# 65). Since the switch S _SP is a spot metering if it is ON, the final photometric value BV3 substituting the spot photometric value BV _SP, because the switch S _SP is an automatic photometric if OFF, automatic photometric value to the final photometric value BV3 Substitute BV2 (# 70, # 7
Five). Next, it is determined whether or not the flag AELF indicating the AE lock is set (# 80). If the flag AELF is not set, the final metering value BV3 is substituted into the metering value BV6 before correction in # 85, and if the flag AELF is set, # 8
Skip 5 and go to # 90 respectively. In # 90, AE
Determine whether the lock switch S _AEL is ON or OFF. If the switch S _AEL is ON, it is determined whether or not a flag AELF indicating AE lock is set (# 95). Flag AELF
If is set, go to # 135. Also the flag AEL
If F is not set, go to # 100 and set the flag AELF
Is set, the correction value BV5 is obtained by (BV2−BV6) in # 102, and the process proceeds to # 135.

If the AE lock switch S _AEL is OFF in # 90, the flag AELF indicating the AE lock is reset, and it is determined whether the override switch Sov is ON or OFF (# 105, # 11).
0). If the override switch Sov is ON, it is determined whether the up switch Sup has changed from OFF to ON (# 115). If the up switch Sup has changed to ON from OFF, then added to the correction value BV4 a predetermined value BVK (e.g. _^1/8 EV), the process proceeds to # 135 (# 120). Up switch Sup is O
Unless it changes from FF to ON, down switch Sdn
It is determined whether or not has changed from OFF to ON (# 125). If the down switch Sdn has changed from OFF to ON, the predetermined value BVk is subtracted from the correction value BV4, and the process proceeds to # 135 (# 13).
0). When the override switch Sov is OFF at # 110,
Alternatively, when the up switch Sup or the down switch Sdn has not changed from OFF to ON in # 115 and # 125, the process directly proceeds to # 135 without changing the correction value BV4. # 135
Then, add the obtained correction value BV4 to the photometry value BV6 before correction,
The photometric value for control is BV.

Here, the difference between the correction values BV4 and BV5 will be described. The correction value BV4 is a manually set override amount,
By operating the up / down switches Sup and Sdn while turning on the override switch Sov, it can be increased or decreased in BVk units. Since the correction value BV4 depends on the personality and preference of the photographer, it generally differs depending on the photographer and also depending on the scene of the subject. On the other hand, the correction value BV5
Is a correction value depending on the reflectance of the subject, and may vary depending on the photographer, but mainly depends on the scene of the subject. This correction value BV5 is AE in spot metering mode.
This is set by locking, and corresponds to the luminance difference between the spot metering value BV _SP and the automatic metering value BV2 when the AE lock is performed. Since the automatic photometric value BV2 is a photometric value whose exposure has been automatically corrected by scene discrimination, it is desired that the photometric value is appropriate for an arbitrary scene. However, for a scene, the photographer selects the spot metering mode
AE lock means that the automatic metering value BV2 determined by the camera is not suitable for the scene.
Therefore, in such a case, if the photographer desires, it is necessary to learn the brightness difference between the AE-locked spot metering value BV _SP and the automatic metering value BV2 as an exposure correction value for the scene. is there. For example, when a person is photographed using an automatic photometry mode before learning in a backlight scene, the person is often crushed in black because the background is brighter. In such a case, select the spot metering mode, put a person in the spot metering area, find the spot metering value BV _SP , use AE lock and use it for exposure control, so that the person will be properly exposed. Will be taken. And
If the brightness difference between the spot metering value BV _SP and the automatic metering value BV2 used for the exposure at this time is learned as the correction value BV5 for the backlighting scene, then in the automatic metering mode, the person will be properly exposed even in the backlighting scene. The possibility of being shot is increased. When the AE lock is performed in the automatic photometry mode, the photometry value BV6 before correction becomes equal to the automatic photometry value BV2, and thus the correction value BV5 becomes zero.

Next, proceeding to # 140 in FIG. 6, the learning mode switch S
_It is determined whether _Q has changed from OFF to ON. If this switch S _Q has changed to ON from OFF, it is determined whether the flag LMF showing a learning mode is set (# 145). If the flag LMF is set, the flag LMF is reset. If the flag LMF is reset, the flag LMF is set, and the process proceeds to # 165 (# 150, # 155). In addition, the learning mode switch S _Q is unless the changes to ON from OFF, nothing proceed to # 165 without. In # 165, photometric value BV, film sensitivity
Exposure value EV (that is, a combination of shutter speed TV and aperture value AV) is calculated by performing a predetermined calculation from SV, and in # 170, a display subroutine (described later) is executed. When the display is completed, it is determined whether the release switch S2 is ON or OFF (# 175). If the release switch S2 is OFF, it is determined whether the input port P10 is at a "High" level or a "Low" level (# 205). If the input port P10 is at “High” level,
Photographing preparation switch S1, AE lock switch S _AEL, none of the learning mode switch S _Q is that the OFF, proceed to # 200, and stopped to erase the display. Input port P10 is “L”
If ow "level, photographing preparation switch S1, AE locking switch S _AEL, it means that either the learning mode switch S _Q is ON, the flow returns to # 10 of FIG. 5. # 175
, If the release switch S2 is ON,
Exposure control is performed based on the shutter speed TV and the aperture value AV obtained in 165 (# 180). Thereafter, it is determined whether or not the learning mode is set by the flag LMF (# 185). If the flag LMF is not set, it is determined that the learning mode is not set, and the process proceeds to # 200. If the flag LMF is set, the learning mode has been set, so the flag LMF is reset and the learning mode is released (# 190). And spot metering switch S
_It is determined whether the _SP is ON or OFF (# 191). Switch S _SP is OFF
Then, it is not the spot metering mode, and # 195
To learn and go to # 200. If the switch _SSP is ON, it is determined that the mode is the spot metering mode, and the process advances to # 192 to determine whether the AE lock switch S _AEL is ON or OFF. If the switch S _AEL is OFF, the process proceeds to # 200 and learning is not performed. If the switch S _AEL is ON, the above-described correction value B is set at # 193.
V5 (= BV2-BV6) is set as the exposure correction value BV4, and the process proceeds to # 195.
In # 195, the scene of the subject is determined from the reference photometric value BVrf, the photographing magnification β, and the luminance difference ΔBV, N correction values ΔBVci stored for the scene are called, and the content is updated by one. That, i = 2, ..., N for, by substituting ΔBVci the same order ΔBVc _(i-1), the oldest entered to erase the correction value DerutaBVc _1, said exposure correction value BV
4 inputs as the newest correction value ΔBVc _N. And
Proceed to # 200, delete the display, and stop.

Next, FIG. 8 (a) shows the contents of the display by the display circuit DSP.
This will be described with reference to (f). FIG. 8A shows a display circuit DS.
P shows a state in which all displayable segments are displayed in the field of view of the finder. In the figure, reference numeral 10 denotes a photographing screen that can be seen when looking through a viewfinder of a single-lens reflex camera. In order to display the image on the photographing screen 10, a guest-host type transmissive LCD (liquid crystal display panel) is arranged on the focus screen of the finder optical system. The display in the shooting screen will be described. 11 is a mark displayed when the learning mode is set. Reference numeral 12 denotes a spot metering area, which is the same as the central part SP of the photographing screen shown in FIG. Numeral 13 is a numerical value representing a deviation from this reference value as an EV value, with the reference value being 0. If the sign of the numerical value is plus, it indicates that the exposure is over, and if it is minus, it indicates that the exposure is under. 14 is a scale bar provided for each _^(1/2) EV. 15 is an index for displaying the deviation, and the scale bar
Along 14 _^(1/2) are arranged 13 every EV, 8
As shown in FIGS. 8B to 8F, it is individually determined whether to display an index with a white triangle “△”, to display an index with a black triangle “▲”, or not to display. You can choose. Next, reference numeral 20 denotes a display unit in the finder displayed at a lower portion of the photographing screen 10, and includes a control shutter speed display unit 21, a control aperture value display unit 22, and an override display unit 23. In the override display section 23, a sign “+” or “−” surrounded by a square is displayed when the exposure correction is being performed, and is blank when the exposure correction is not being performed.

Hereinafter, various cases will be described with reference to specific display examples. FIG. 8B shows a display example in a normal photometry state (only the photographing preparation switch S1 is ON). Since the automatic photometry mode is set, the spot photometry area is not displayed. When the reference photometric value BVrf (spot metering value BV _SP or the average light measurement value _{(BV SP + 8BV AM) /} 9) ( numeric point 0) the scale bar origin was, as a deviation therefrom, in an automatic light measuring mode Is indicated by a black triangle “▲”. In addition, a control shutter speed and a control aperture value based on a photometric value in the automatic photometric mode are displayed below the outside of the shooting screen.

Figure 8 (c) is in the ON spot metering switch S _SP, a display example when selecting a spot metering mode, spot metering area is displayed in the center of the shooting screen. When the reference metering value BVrf is used as the origin of the scale bar,
As deviations therefrom, the spot photometric value is indicated by a black triangle “▲” index, and the photometric value in the automatic photometric mode is indicated by a white triangle “Δ” index. At this time, the average photometric value is selected as the reference photometric value BVrf. If the spot photometric value is selected, the black triangle “▲” is displayed at the origin of the scale bar. . Note that a control shutter speed and a control aperture value based on the spot metering value are displayed at the lower part of the shooting screen.

FIG. 8D is a display example when the learning mode is set in the spot metering state and the AE lock switch S _AEL is turned ON, and a mark indicating the learning mode is displayed at the upper right end of the shooting screen. ing. When exposure control is performed in this state, the difference between the photometry value in the automatic photometry mode and the spot photometry value is learned, and is fed back to the next photometry value in the automatic photometry mode.

FIG. 8E is a display example when an override (exposure correction) is applied in the spot metering state, and the reference metering value is shown.
When BVrf (here, the average photometric value) is set as the origin of the scale bar, the control value that has been overridden (the exposure value used for control) is indicated by a black triangle “▲” as a deviation from that. In addition, the spot metering value before the override is applied is displayed by blinking a white triangle “△”. Here, the reason why the white triangle “Δ” is blinking is that only at this time, the index indicates the spot photometry value, not the photometry value in the automatic photometry mode. At the lower right of the outside of the photographing screen, a “−” mark is displayed on the minus side to indicate that the override is applied.

FIG. 8 (f) is a display example when the override is applied in the automatic metering mode. When the reference metering value BVrf (spot metering value or average metering value) is set as the origin of the scale bar,
As a deviation therefrom, the control value that has been overridden is indicated by a black triangle “▲”, and the photometry value in the automatic metering mode before the override is applied is indicated by a white triangle “△”. It is displayed by the index of. In the automatic metering mode, when the learning mode is set,
A mark indicating the learning mode is displayed irrespective of ON / OFF of the AE lock switch S _AEL .

8 (b) to 8 (f), the shutter speed and the aperture value for the exposure control are all the same value, but these may be changed by the correction of the exposure amount or the change of the luminance of the object scene. Needless to say.

Next, the subroutine (# 170) of the above-mentioned display will be described with reference to FIG. When this subroutine is called,
The shutter speed TV and aperture value AV are displayed, and BV7 (= BV-BVr
f) The index of “▲” is displayed at the point where becomes, and the exposure compensation value BV4
Is determined to be 0 (# 250 to # 300). Exposure compensation value BV
If 4 is 0, the display of "+" or "-" override is erased, and it is determined whether the spot metering switch _SSP is ON or OFF (# 302, # 305). Spot metering switch S _SP
If it is OFF, the above-mentioned "▲" indicates the deviation of the automatic photometric value from the reference photometric value.
Then, the index of “△” is deleted, and the process proceeds to # 335. If the spot metering switch _SSP is ON in # 305, the above-mentioned "▲" indicates the deviation of the spot metering value from the reference metering value. In order to also display the deviation, an index of “△” is displayed at a location where BV8 (= BV2−BVrf) at # 315, and the process proceeds to # 335. If the exposure correction value BV4 is not 0 at # 300, an override of "+" (over) or "-" (under) is displayed according to the value of the exposure correction value BV4 (# 320). And # 325
To determine whether the spot metering switch _SSP is ON or OFF. #
If the spot metering switch _SSP is OFF at 325, the above-mentioned “▲” indicates the deviation of the exposure-corrected automatic metering value from the reference metering value. The process proceeds to step # 315 to display the deviation of the automatic photometric value from the reference photometric value. Also, if the spot metering switch _SSP is ON at # 325, the above-mentioned index of “▲” indicates the deviation of the exposure corrected spot metering value from the reference metering value. In order to display the deviation of the spot metering value from the reference metering value before the reference, the process proceeds to # 330, where the indicator of “点 滅” is displayed while blinking at the point of BV8 (= BV3−BVrf), and then to # 335. move on. As is clear from the above description, the index of “▲” indicates the deviation of the photometric value used for the final control from the reference photometric value,
The indicator of “△” indicates the deviation of the automatic metering value from the reference metering value, and the blinking display of the indicator of “△” indicates the deviation of the spot metering value before exposure correction from the reference metering value. .

In # 335, whether or not the learning mode is set is determined by the flag LMF. If the flag LMF is 1, the learning mode is set, and it is determined at # 340 whether the spot photometry switch _SSP is ON or OFF. Spot metering switch S
_{If SP} is ON, AE lock switch S _AEL is ON or O at # 345
Determine whether it is FF. If the AE lock switch S _AEL is ON,
In step # 350, a mark indicating the learning mode is displayed. If the AE lock switch S _AEL is OFF, the display of the mark indicating the learning mode is deleted in # 355, and the process proceeds to step # 360. When the spot metering switch _SSP is OFF at # 340, A
Regardless of the state of the E lock switch S _AEL , the process proceeds to step # 350 to display a mark indicating the learning mode, and the flag L is set in step # 335.
If the MF is not 1, the process proceeds to step # 355, where the display of the mark indicating the learning mode is deleted. In # 360, it is determined whether the spot metering switch _SSP is ON or OFF. If ON, the spot metering area is displayed in # 365, and if OFF, the display of the spot metering area is deleted and the process returns.

Finally, among the variables used in this embodiment, variables relating to the photometric value are listed below.

BV: Metering value for control BV _SP : Spot metering value BV _AM : Perimeter metering value BV _AV : Average metering value = (BV _SP + 8BV _AM ) / 9 ΔBVci: N exposure correction values learned for a certain scene ΔBVc: Same as above Average value BV1 Multi-segment metering value = kBV _SP + (1-k) BV _AM BV2 Automatic metering value = BV1 + ΔBVc BV3 ... Final metering value (BV2 or BV _SP ) BV4 ... Correction value depending on personality of photographer BV5: Correction value depending on the reflectance of the subject BV6: Metering value before manual exposure correction [Effect of the Invention] In the camera according to the present invention, the photographer performs AE lock on the spot metering value and performs exposure. In this case, the difference between the proper exposure value based on the spot metering value and the automatic exposure value determined by the camera is learned, and the subsequent automatic exposure value is made closer to the proper exposure value. You can learn the required exposure compensation amount without having to do it manually. There is an effect that.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic configuration of the present invention, FIG. 2 is a block circuit diagram of a camera as one embodiment of the present invention, FIG. FIG. 8 is a flowchart for explaining the operation of the above, and FIG.
(F) to (f) are explanatory views of the display in the finder. 1 is a spot metering means, 2 is a multi-segment metering means, 3 is a metering value correcting means, 4 is an exposure calculating means, 5 is a selecting means, and 6 is an AE.
Lock operation means, 7 is a correction value storage means, and 8 is a correction value prediction means.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Koji Hata 2-3-2, Azuchicho, Chuo-ku, Osaka-shi, Osaka-shi Osaka International Building Minolta Camera Co., Ltd. (72) Inventor Akihiko Fujino Azuchi, Chuo-ku, Osaka-shi, Osaka 2-3-3, Osaka-cho, Osaka International Building Minolta Camera Co., Ltd. (56) References JP-A-60-258522 (JP, A) JP-A-2-20841 (JP, A) (58) Fields investigated (Int) .Cl. ⁶ , DB name) G03B ^7/ 00-7/28

Claims (1)

(57) [Claims] 1. A spot metering means for metering a small area at the center of a shooting screen and outputting a spot metering value, and a multi-segment metering means for metering areas of a plurality of portions of the shooting screen and outputting a multi-segment metering value. And a photometric value correction unit that adds a correction value to the multi-segment photometric value obtained by the multi-segment photometric unit to obtain an automatic photometric value, and calculates an exposure value used for control based on the automatic photometric value or the spot photometric value. Exposure calculation means, selection means for selecting whether to use automatic or spot metering for exposure value calculation, AE lock operation means manually operated, and spot metering for exposure value calculation If the AE lock operation unit is operated when using, a correction value storage unit that stores a brightness difference between the spot metering value and the automatic metering value after the exposure is completed, and a metering value correction unit based on the storage content of the correction value storage unit. More A correction value predicting means for predicting a correction value to be added to the divided photometric value in a direction in which the automatic photometric value becomes an appropriate value.