JPH01280735A - Image pickup provided with color temperature detecting device - Google Patents

Abstract

PURPOSE:To perform excellent color temperature detection in simple constitution by reading the color temperature information of a light source irradiating on an object, automatically emitting a flash light when an illuminating light is not a solar light and trying color reproducibility by means of a flash close to the solar light. CONSTITUTION:When a shutter button is turned into semi-pushed condition by a photographer, defocus amount is calculated by a system controller not shown in a figure based on the output of a focus detecting sensor 7 and a photographing lens 1 is driven based on the defocus amount and is focused. After focusing the object is finished, the brightness of the object is measured by means of a metering sensor 6. Based on the brightness information, the system controller calculates the electric charge accumulating time of a solid- state image pickup element 9, therefore, shutter opening time, the time of the timing when the flash is necessary or not and the time of the timing of the emission of the flash. When the shutter button is fully pushed by the photographer and enters a release, a main mirror 3 is lifted, and a sub-mirror 4 is folded up, and exposure to the element 9 is started.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention provides a flash device and a color temperature detection device [i
The present invention relates to imaging devices such as electronic still cameras and video cameras.

[Prior art] Traditionally, flash photography has been used to provide an appropriate amount of light to low-brightness subjects, compensate for insufficient light on the shooting screen, or apply exposure compensation for backlit or low-contrast subjects. This is done to correct the contrast of the screen.

On the other hand, in video cameras and the like, if the color temperature of the light shining on the subject changes, the color balance of the image changes, so it is possible to automatically adjust the appropriate color balance according to the color temperature of the light source. A so-called auto white balance device is used. However, such devices have complicated circuit configurations.

Therefore, as a simple configuration, there is a shooting mode that allows optimal shooting under sunlight during the day (i.e., a shooting mode for color temperature or day 1 ~), and a shooting mode that allows for optimal shooting under sunlight. Some cameras allow you to manually switch between shooting modes when using incandescent (tungsten) light. In such a device, when the completion of the flash preparation operation of the flash device is not detected, the imaging device is configured to switch to the shooting mode of day 1 to river color temperature even if the shooting mode is set to the tungsten color temperature. have been proposed (for example, see Japanese Patent Laid-Open No. 58-1.47721).

However, the device described in item 1 is a device that allows you to manually switch the balance to Why 1 between daylight mode and tungsten light mode, and even if it is set to tungsten light mode, once the flash is fully charged. , the camera is forced to switch to a shooting mode that is suitable for the color temperature of the flash light and corresponds to daylight.

In addition, for cameras that detect the color temperature and balance from O 1 to Pow 1, if the flash is not ready to fire, the color temperature is fixed at a predetermined constant color temperature, for example, the white balance of daylight color. (for example, Japanese Patent Application Publication No. 6
3-59290), and furthermore, a device that is equipped with a flash whose color temperature is variable and causes the flash to emit light at a color temperature that achieves a measured or set color temperature (for example, (See Publication No. 58-149033) has been proposed.

[Invention or Problem to be Solved] In the former two prior art described in L, neither detects the color temperature of the subject and fires the flash when it is not daylight; Therefore, it is not possible to fix the white balance circuit to daylight color.
There are limits to the simplification of the concave radius configuration.

The present invention solves these problems, and aims to provide an imaging device equipped with a color temperature detection device that can fix the white balance circuit to daylight color and simplify the circuit configuration. shall be.

[Means for Solving the Problem 1] The present invention includes a means for detecting the color temperature of a subject and outputting information regarding the color temperature, and a means for detecting the color temperature of a subject, and a means for outputting information regarding the color temperature, and a means for detecting a light source illuminating the subject based on the color temperature information. and a means for outputting a flash light instruction signal when it is determined that the light source is different from sunlight.
This is an imaging device equipped with a color temperature detection device made by iTi.

[Function] According to this configuration, the color temperature information of the light source illuminating the subject is stolen, and when the illumination light is not sunlight,
Flash light is automatically emitted, and color reproducibility is improved with the flash light having a color temperature close to that of sunlight.

[Example] FIG. 1 shows a configuration diagram of an optical system according to an example of the present invention. In the figure, 1 is a photographic lens including a zoom lens, and 2 is a half mirror 33 with a low reflectance that guides a part of the light transmitted through the photographic lens 1 to the photometric sensor 6. A main mirror 4 which is a reflecting mirror and guides the light transmitted through the mirror 2 to a pentaprism 51\.
5 is a sub-mirror that totally reflects the light that has passed through the center of the main mirror 3 and guides it to the focus detection sensor 7, 5 is a pentaprism that guides the light reflected by the main mirror 3 to a finder (not shown), and 8 is an optical The low-pass filter 9 has a shutter function 71 to a solid-state image sensor (
An example is a CCD.

-5= The photometric sensor 6 is a photoelectric conversion element (for example, 5PC)
It has two types of sensors: one that measures light at the center of the shooting screen spot-wise and one that measures light around the periphery of the shooting screen. The sensor 6 is located at a position where the distance Rb between the reflection point A of the half mirror 2 and the photometric point B of the sensor 6 is equal to the distance Rc from the reflection point A to the imaging point C of the solid-state image sensor 9. It is arranged so as to be equivalent to performing photometry on the imaging surface of the solid-state image sensor 9. In addition, the sensor 6 is placed in a position where it is not blocked from light regardless of whether the light is being received or whether the main mirror 3 is up or down, so that it can simultaneously measure light even when the solid-state image sensor 9 is exposed when the mirror is up. It has become.

The focus detection sensor 7 has, for example, two CCD line sensors that each receive images from different exit pupils of the photographic lens, and uses a phase difference detection method of the two images to determine the amount of focus shift or detect the amount of focus. It detects the amount of focus.

In the above configuration, when the photographer presses the shutter button halfway, the external system controller calculates the defocus amount based on the output of the focus detection sensor No. 7, and based on this, the photographic lens 1 drive to focus. After the subject has been focused, the photometric sensor 6 measures the subject's yef1 degree, and based on the brightness information, the charge accumulation time of the system controller 1 to the roller or the solid-state image sensor 9 (i.e., the shutter opening time), whether or not a flash is necessary, and the timing of flash emission are calculated. When the photographer fully presses the shutter button to release the camera, the main mirror 3 is flipped open, the sub-mirror 4 is folded, and exposure to the solid-state image sensor 9 is started.

Suddenly, the solid-state image sensor 9 starts accumulating charges.

Furthermore, at the same time as the charge is accumulated in the solid-state image sensor 9, the photometric sensor 6
starts photometry, and when it detects that the amount of photometry has reached an appropriate exposure value, it stops accumulating charges in the solid-state sensor element 9, transfers the accumulated charges to the analog memory section, and takes pictures. finish.

In addition, in the configuration of this embodiment, while taking the configuration of an eye reflex camera, the solid-state image sensor 9 has a shutter function,
Furthermore, the aperture mechanism was removed in order to make the camera more compact and simplify the mechanism. Therefore, the main mirror 3 and sub-mirror 4 placed in front of the solid-state image sensor 9 are configured to completely shield the low-pass filter 8 and the solid-state image sensor 9 from light, and are The image sensor 9 may be damaged by forming an image or by being irradiated with light for a long time.
This prevents color fading (burning) of a color filter (not shown) provided on the front surface of the camera, and also prevents the solid-state image sensor 9 from accumulating unnecessary charges at times other than when the camera is released.

Next, FIG. 2 shows the system configuration of this embodiment.

In the figure, 10 is a system controller 1-roller (CPUI) that controls the sequence of the entire camera section.23
11 is a system controller (CPU 2) that controls the sequence of the video section. Also, 11 is a focus detection CC that drives the lens and automatically focuses (AF).
There is a control circuit block consisting of a D line sensor and an interface circuit section, and system
The AP sequence controls the charge accumulation function and the function of sequentially A/D converting and outputting the accumulated charges. Further, 12 is a DC/DC converter that generates different power supply voltages for each circuit block and supplies power;
13, the power of the motor M is connected to the photographing lens 1 and the main mirror 3.
14 is an auxiliary light source of the AP (LED
) and a light source such as an LED that blinks while the self-timer is operating, 15 is a driving IC 116 that drives the motor M, and a photo I that generates a number of pulses according to the amount of driving of the photographing lens.
~It is a coupler. Further, 17 is a photometric sensor, and a sensor 17a that measures the brightness at the center of the shooting screen with a spot.
and a sensor 17b that measures the brightness around the shooting screen except for the center. Also, 18 is a flash circuit, 19 is an LED display circuit 19a in the viewfinder, and an LCD display circuit on the top of the camera body! ? a display circuit having an 819 b;
Reference numeral 20 indicates a color temperature sensor circuit for measuring the color temperature of the light source illuminating the subject-9=body, and 21 indicates switches including a switch linked to the shutter button and a mode changeover switch.

Here, each switch of the switches 21 is shown. SO is the main switch that prohibits camera operation when it is "open", and SL starts AE (auto exposure) and AP (auto focus). S2 is a release start switch.

S3 and 84 are used to set the amount of correction at the manufacturing stage of the camera in accordance with the variation in the imaging sensitivity (that is, the sensitivity of the output voltage to a constant exposure amount) corresponding to the ISO sensitivity of the film of the solid-state imaging device 9, which is individually different. is the switch of
Signals (A, B) to 2 pins 1 with these switches s3 and S4
are configured, and the corresponding correction values γ [EV] are stored in the system controller 10.
When the bit signals (A, B) are input to the system controller 1o, the system controller 1o outputs a correction value γ corresponding to the signal, and the luminance measured by the photometric sensor 17 is subjected to an IF.

In other words, the photometric sensor 17a performs photometry at the same time as shooting, and the shutter speed is controlled based on the timing of opening the shutter shutter or the photometric data, so the shutter speed is controlled by correcting the photometric data, and the imaging sensitivity is corrected. It is something that will be done. For example, (0,0)=O,OEv, (0,1
)=+0.3Ev, (1,0)=-0,3Ev, (1,
1>-10, 5Ev, and if the imaging sensitivity of the solid-state image sensor 9 is 0.3Ev larger, the 2-bit signal (0, i) is sent to the system controller l-roller 10 with the same manual deviation. + corresponding to controller 10 to 0゜1)
The correction value γ of ○, 3Ev is output, and the photometric brightness of the photometric sensor 17 is corrected by +○, 3Ev, so the shutter speed becomes +0.3Ev faster and the exposure amount is lowered by 0.3Ev. Variations in image sensitivity are corrected. Note that by increasing the number of switches and increasing the number of bits and storing correction values corresponding to each pill signal in memory, the amount of correction can be made finer.

85 is a date switch consisting of a 1.0 switch S for selecting date 1 to information of the year, month, day, hour, and minute, and a second switch S for setting and modifying the selected date information; is a teller 8 tube detection switch that detects whether the deck lid is open or closed, S is a floppy detection switch that detects whether or not a floppy disk for video signal recording is loaded in the camera, This is a write-protection detection switch that detects whether or not write-protection is selected by the write-protection selection tab on the disk.

S8 is a switch for detecting whether the accessory slide copier is connected, and S is a switch for detecting whether the accessory slide copier is connected.

S10 is a switch that detects the playback mode, and S11
is a field/frame switch that changes the recording format to field or frame.
S12 is a zoom encoder switch group that monitors the focal length of the zoom lens.

313 is a forced flash switch for forcing the flash to fire regardless of the brightness of the subject, and S14
315 is a flash prohibition switch for forcibly disabling the flash, and 315 is a mode changeover switch for switching between single and self-timer shooting modes.

Next, reference numeral 22 denotes a control IC, which includes a control circuit that controls the drive of each actuator such as the DC/DC converter 12 and the clutch 13 according to the control signal from the system controller 10, and the shutter speed and flash of the solid-state image sensor 9. It includes a control circuit for controlling the light emission timing of the circuit 18, an A/D conversion circuit for photometric data from the photometric sensor 7, a proper exposure detection circuit, and the like.

To explain this control TC22, the voltage control circuit 2
2a is DC/DC controller 1~D C/D by roll signal
The clutch control circuit 22b controls the on/off of the clutch 13 using a clutch control signal, and the self-control circuit 22c controls the light emission of the light source 14 using a self-control signal to control the motor. The circuit 22d controls starting of the motor M using a motor control signal. Further, the photo 1 to interrupter circuits 22e count the number of pulses corresponding to the amount of lens rotation output from the photo coupler 16, and output the pulses to the system controller 10. In addition, the amplifier circuit 22
f and 22f are respectively spot photometry sensors 17
a and the peripheral photometry sensor 17b are converted into logarithmically compressed voltage signals and outputted, and the output signals are sent to the double integral control circuit 2 via the switch SWI.
2g. In addition, the same control circuit jitlQ22g switches the switch SWI, and the amplifier circuits 22f and 22
The analog signal output from f is captured, converted to a digital signal, and sequentially sent to the system controller 1.
Output to 0.

Reference numeral 22i is a circuit for starting exposure of the solid-state image sensor 9 in response to the "shaft open" signal, and determining whether the exposure amount has become appropriate based on a detection signal from the photometric sensor 17a. The configuration of the circuit 22i for detecting this proper exposure is as follows:
connected to the base of transistor Q,
has its emitter grounded and its collector connected to the inverting input terminal of comparator CP. Further, the collector of the transistor Q is connected to the negative electrode of a capacitor C, and the positive electrode of the capacitor C is connected to a power supply terminal Vcc<not shown. Further, the power supply terminal Vcc is connected to the positive pole of the constant voltage source B, and the negative pole of the identified voltage source B is connected to the normal input terminal of the comparator CP.

In addition, a switch SW2 is connected between the positive and negative electrodes of the capacitor C.
The switch SW2 is controlled to open and close by the output of "Shutter open" from the system controller 1 to the roller 10.

In the proper exposure detection circuit 22i, when the switch SW2 is switched from "close" to "open" by the above-mentioned "shutter open" signal, the capacitor C is charged by the collector current of the transistor Q, and the capacitor C is charged by the collector current of the transistor Q. Negative electrode potential (
V), and the voltage at the normal input terminal of the comparator CP (V o
), the output of the comparator CP is inverted to detect proper exposure, and this detection result is output to the system controller 10 and the shutter control circuit 22n as a signal instructing the shutter to "close". .

Next, the D/A conversion circuit 22h is connected to the system controller 1.
The brightness correction amount output from 0, for example, the above-mentioned ISO
It converts the adjustment amount for sensitivity variation adjustment from a digital signal to an analog signal, and the correction signal or adder M1
The signal is input to the photometric sensor 17 and added to the light reception signal of the photometric sensor 17.

The battery check circuit 22j checks the capacity of the battery. In addition, the flash 1-recovery circuit 22 emits one flash to the flash circuit 18 in response to a flash emission signal input from the system controller 10.
Outputs a tri-force signal. In addition, the flash control circuit 2
2m is the flash circuit 1 by the control signal of "Start boosting"
8 (hereinafter referred to as charging of the flash circuit) to the main capacitor for light emission of flash circuit 18.
detects the charging state of the battery and outputs a charging completion signal to the system controller 10.

22n is a shutter control circuit that outputs a shutter opening/closing signal, which outputs a shutter "open" control signal from the system controller 10 and a detection signal from the proper exposure detection circuit 22i, or a forced termination signal from the system controller 10. Control signals for shutter "open" and "close" are output to the system controller 23 and the time control circuit 24.

The time control circuit 24 performs the shutter control time 1?
The start and end of exposure of the solid-state image sensor 9 is controlled by the shutter "open" and "close" control signals inputted from the shutter 422n. The video processing control circuit 25 adjusts the video signal based on the gain correction amount input from the system controller 10 and the color temperature information input from the system controller 23, and also adjusts the video signal based on the amount of gain correction input from the system controller 10 and the color temperature information input from the system controller 23. The recording signal also controls whether the recording track is one track or two tracks. Here, the details of the gain correction amount will be described later, or
Frontlight-1, "Backlight", "Far-range", = 17- Determined by each mode such as "Flash mode", "Forced flash", etc.-1. OBv, -Q, 5Ev, 10, 5Ev,
+1. This is the correction amount of OEv. Further, 26 is a magnetic head and a disk for recording, and 27 is a spindle motor that rotationally drives the disk 26. The system controller 23 also sends map information (empty track, recording end 1
- easy information), information indicating that the system controller I/roller 10 cannot accept switches such as recording, head feeding, etc. is sent.

Next, in FIG. 2 showing the system configuration, there is a shutter control circuit 22n that outputs shutter "open" and "close" signals for shutter opening/closing operations, and a proper exposure detection port FM 22.
i and the system controller 10 will be mainly explained.

First, when the system controller 10 outputs a shutter "open" signal, it is input to SW2, starts charging the capacitor C of the detection circuit 22i, and is also input to the EXOR circuit 31 of the shutter control circuit 22n.

Since ``L'' is input to the input terminal at the other end of the EXOR circuit 31, the EXOR circuit 31 outputs ``°)]'' to the time controller 24 and the system controller 23, and the solid-state imaging probe 9 In addition, the system controller 10 starts the time count of the flash emission time at the same time as outputting the shutter open signal only when the flash is necessary, and if the time count of the flash emission time has not finished, A flash trigger signal is output from the system controller 1o to the flash trigger circuit 22, and the flash starts emitting light.

Next, when the detection circuit 22i does not detect proper pressure exposure, a shutter "close" signal H''' is output from the device CP to the system controller 1o and the OR circuit 32.OR circuit 3
2 receives the above ``H'' output, E X OR times + Wr
3] 6Z outputs "H", and the E and notifies the time controller 1-0-controller 24 of the end of exposure.If the timing at which the detection circuit 22i outputs the shutter "close" signal from =19- is later than a predetermined time (shake limit time), the system controller A forced termination signal "H'" is output from 10 to notify the end of exposure in the same manner as in the operation described in section 1.

The system controller 10 controls the timing of outputting the shutter "open" signal, the timing of inputting the shutter "close J signal, the timing of outputting the forced end signal (shake limit time), and modes such as "frontlight" and "backlight". The gain up/down (details will be shown later) is calculated and output to the video processing control 411!425.

28 is a communication line between the system controller 10 and the system controller 23;
For example, switch information signals such as S, S, date, playback, field/frame, slide copier, Nekacobia, write or write inhibit, floppy detection, spindle motor ON-OFF, and current track number.

etc. control signals are sent.

Next, the photometry mode classification of subject brightness based on photometry information will be explained using Table 1. As shown in the table, the subject brightness metering mode is divided into "bright" mode, which allows shooting using only natural light, and "dark" mode, which requires auxiliary light from a flash. For each case of ``Front Light -1'', the balance between the brightness of the main subject on the shooting screen and the brightness of the secondary subject in the background is appropriate.
There are four types: backlighting, where the brightness of the main subject on the photographic screen is relatively lower than the brightness of the secondary subject in the background; Note that ``sunkyo'' also includes renzuhitsu.

In addition, there is an ``auto mode'' that automatically determines whether or not the flash is necessary based on the metering results for each of the four types of metering modes and selects the appropriate shooting method, and an ``auto mode'' that automatically determines whether or not the flash is necessary based on the metering results and selects the appropriate shooting method. Take a picture using the flash [
Three types of shooting modes are supported: a forced flash mode j, and a ``flash prohibition mode'' that forcibly prohibits flash emission even when auxiliary light from a flash is required. In addition, in the same table, "forced flash" and "flash prohibition 1" are shown as "forced flash mode" and "r flash prohibition mode" respectively, and "flash" or "AE (flash prohibited)"
It shows the photographing mode selected by ``O1 Mode''.

By the way, if we classify the shooting methods in the above-mentioned shooting modes based on whether or not a flash is required, there are two types: "Natural light mode", which uses only natural light without using the flash, and "Natural light mode", which uses only natural light without using the flash, and "Natural light mode", which uses the flash and uses both natural light and flash light. It is divided into "flash mode" for taking pictures. In the photometry mode classification in Table 1, "flash off" and r
AE (flash off)" or "natural light mode", and [forced flash J and "flash" or "flash mode"].

Next, the photographing method of the photographing mode for each photometry mode of this embodiment will be explained.

(1) About [Natural Light Mode]; In this mode, when shooting in bright backlit conditions with flash off mode, the brightness of the sub-subject is relatively bright compared to the brightness of the main subject. Therefore, if the main subject is photographed with the proper exposure, the background sub-subject will be photographed with brightness. In this way, the photometered brightness of the main subject is corrected by +0°5 Ev, and when the main subject becomes properly exposed, the exposure is stopped. By shooting in this way, the main subject will be exposed at 0.
．． Although the image is taken at a low 5Ev, the background is prevented from being photographed too brightly at the @ end, and the overall image is taken beautifully.

Next, when shooting in "flash off mode" in the case of "dark backlight", the brightness of the secondary subject is relatively brighter than the brightness of the main subject, but the brightness of the secondary subject in the background is darker than the brightness of the main subject. Even if a photograph is taken with proper exposure, the subject in the background will not be photographed too brightly. In this way, the photometered brightness of the main subject is not compensated for, and the main subject is photographed with proper exposure.

Also, when shooting in "flash off mode" in "dark front light" and "bright front light" in rAE (flash off), the balance between the main subject's brightness and the sub-subject's brightness is relatively appropriate. In this case, the brightness of the entire shooting screen is bright and dark, so the average brightness (Bvs') is calculated by taking into account both the brightness of the main subject and the brightness of the sub-subject, and calculating the weighted average of each brightness. 6. If the brightness of the entire shooting screen is very low to the limit value of photometry, the above average brightness will be the difference between the brightness of the main subject and the brightness of the sub-subject. The weight of brightness is increased. Additionally, if the brightness of the shooting screen falls significantly below the photometry limit, the release will be locked and shooting will not be possible.

(2) Regarding "flash mode": In this mode, in "1 forced flash mode", it is thought that the photographer's intention was to take a picture using the flash light source regardless of the brightness of the main subject, so the metering Regardless of the mode classification, the flash is emitted by the shutter "open" control signal, and the main subject is photographed with proper exposure.

In addition, in the case of "bright backlight" (hereinafter referred to as "backlight flash mode"), the luminance of the metered subject is -1.
, 013■ is applied to calculate the appropriate exposure time for the sub-subject, and the correction value J is calculated.

If the APEX value of the exposure time obtained by subtracting OEv is Tv, then after the start of shooting, after exposure to natural light until the exposure time T'v described by -,Ix, the flash is fired and when the main subject becomes suitable, foggy light Shoot to stop.

That is, the background is photographed using natural light with IEv brighter than appropriate, and then the main subject is photographed appropriately using flash light. By photographing in this manner, the main subject can be photographed clearly, and the sub-subject can be photographed brightly relative to the main subject, creating an atmosphere of backlight.

In addition, in the case of "dark backlight" and "sunny forward light" (hereinafter referred to as "dark flash mode j"), the metered brightness of the main subject is corrected by +1.OEv, and the main subject is properly exposed. When the APEX value of the exposure time calculated by calculating the time and adding the above correction value 1.OEv is Tv, after starting shooting,
After exposure with natural light up to the exposure time Tv, a flash is emitted and when the main subject becomes suitable, the exposure is stopped and photographed. That is, the main subject is photographed using natural light IEv darker than appropriate, and then the main subject is photographed appropriately using flash light.

By the way, in the above embodiment, the exposure time corresponding to the flash emission timing time is divided into "backlight flash mode" and "dark flash mode" and calculated by the system controller 10, and the exposure time is calculated at the same time as the exposure of the solid-state image sensor 9 starts. However, instead of calculating the flash firing timing time from advance photometry information, the solid-state image sensor 9 is used to measure the secondary subject in [backlight flash mode] and the main subject in [dark flash mode]. You may also use tie-left photometry at the same time as the fog light to obtain the flash firing timing. That is,
In the "backlight flash mode", the sub-subject brightness is directly measured at the same time as the exposure of the solid-state image sensor 9 starts, and 1. When OEv increases, fire the flash,
Exposure ends when the main subject becomes suitable. Also,
In the "dark flash mode", the brightness of the main subject is directly measured at the same time as the exposure of the solid-state image sensor 9 starts, and 1. The flash may be emitted when the OEv is low, and the exposure may be ended when the main subject becomes suitable.

This concludes the explanation of how to shoot in each shooting mode, and next,
A description will be given of dividing the photographing mode into modes based on the brightness of the subject detected by the photometric sensor 17.

The photometric sensor 17 includes two types of photometric sensors: a photometric sensor 17a that spot-meters the brightness at the center of the photographic screen, and a photometric sensor 17b that measures the brightness around the photographic screen. For example, when photographing a person, the main subject, the person, is placed in the center of the shooting screen, and the background, which is the sub-subject, is often placed around the periphery of the shooting screen. The brightness of the subject and the brightness of the sub-subject are measured separately.

By the way, the brightness at the center of the photographic screen measured by the photometric sensor 17a (hereinafter referred to as center brightness) is Bvl, and the brightness around the photographic screen measured by the photometric sensor 17b (
(hereinafter referred to as peripheral brightness) is Bv2, the brightness of the main subject is Bvs, and the brightness of the sub-subject is Bva.The photometric value Bv2 can be used as the brightness Bva of the sub-subject such as the background, but the photometric value Bv1 is the brightness B of the main subject
It is known that when used as a VS, errors may occur. For example, if the main subject is small relative to the shooting screen and is backlit, the background light will wrap around the main subject, and the photometric value Bv1 will be greater than the main subject brightness Bvs. When the ratio of the size of the main subject to the photographic screen is arbitrarily changed by zooming, the error between the photometric value Bv1 and the main subject brightness Bvs changes depending on the ratio. Therefore, it is necessary to correct the photometric value Bv1 to obtain the main subject brightness Bvs according to the ratio of the size of the main subject to the photographic screen or the difference in brightness between the main subject and the sub-subject. That is,
When this correction amount is α, the main subject brightness Bvs is expressed as Bvs=Bv1 −a −■. Note that the unit of subject brightness is expressed in Ev value.

Table 2 is an α map representing the correction amount α.

In the table, β is a photographing magnification indicating the size of the subject relative to the photographic screen, and ΔBv represents the difference between the peripheral brightness BV2 and the central brightness Bvl, that is, ΔBv−Bv2−Bv1. As shown in the table, as β becomes smaller, the ratio of the size of the main subject to the shooting screen becomes smaller, and the amount of light that wraps around from surrounding objects to the photometric sensor 17a increases, so the value of the correction amount α becomes larger. ing. Also, as ΔBv increases, the brightness of surrounding objects will be brighter than the main object, and the backlight will become stronger. This will increase the amount of light that wraps around from the surrounding objects to the photometric sensor 17a, so the value of the correction amount α will increase. There is. However, β or 1/
When it is smaller than 100, the ratio of the size of the main subject to the photographic screen is so small that it cannot be considered as the main subject on the photographic screen, so the correction amount α is not included. In addition, when ΔBv is 2.75 or more, it can be considered that the amount of light that wraps around from the secondary subject to the photometric sensor 17a is small, that is, the main subject is being photometered relatively accurately in strong backlight, and Since the main subject is considered to be relatively large, the value of the correction amount α is set small to take advantage of the shooting conditions.

Here, the above main subject brightness Bvs and sub-subject brightness Bv
The mode division into "frontlight" and "backlight" based on a will be explained.

The brightness difference (B
va-Bvs) is ΔBv', if the sub-subject brightness is larger than the main subject brightness by a certain value (δ), that is, if ΔBv'>δ, the sub-subject's If ΔBv′≦δ is too bright, it is assumed to be backlight j, and if ΔBv′≦δ, it is assumed to be “frontlight” where the brightness of the main subject and sub-subject is balanced.

Table 3 is a δ map giving the above constant value δ. The δ values in the table were determined through actual photography, and the δ values vary in three levels depending on the brightness of the main subject. This is because as the brightness increases, the amount of light that wraps around from the periphery to the center increases, making it difficult to detect backlight, and the constants in Table 3 are selected to accommodate this.

Next, the classification of flash emission modes will be explained.

The exposure time is long, allowing the photographer to reach the maximum brightness (
Hereinafter referred to as camera shake limit brightness) is B v h.
When the overall brightness of the photographing screen is lower than the camera shake limit brightness Bvh, a "flash mode" is set in which a flash is emitted to photograph.

By the way, as for the overall brightness of the shooting screen, since the main subject brightness and the sub-subject brightness are different, the weighted average value 13vs' of the main subject brightness Bvs and the sub-subject brightness Bva taking into account the respective brightnesses is calculated as the average of the entire shooting screen. This will be used as luminance. In the case of "frontlight", Bvs' is given by Bvs'=Bvs/4+(3□ Bva)/4, and when Bvs'≧Bvh, it is set as [frontlight] rush mode J, and when Bvs'<Bvh , since the entire shooting screen is dark, use "dark flash mode".

In addition, in the case of "backlight", the sub-subject brightness is higher than the main subject brightness, so the value (Bva -
δ) will be used.

That is, when Bva-δ≧Bvh, the background is bright,
Since the main subject will be dark due to backlighting, we set the flash to "backlight flash mode" and set Bva-δ<Bv
At the time of h, since Bvs≦Bva−δ<B v h, the entire shooting screen is dark even though it is backlit, so the “dark flash mode” is set.

In addition, if the central brightness Bv1 is lower than the photometric limit value of the photometric sensor 17a, the reliability of the photometric value is low. Weighted average value Bvs with increased weight
' is used to process it as a "low brightness processing mode". That is, using Bvs' calculated as Bvs' = Bvs/8 + (7-Bva)/8, [Dark flash mode]
Process as .

Below are "Natural light mode" and "Dark flash mode"
, "backlight flash mode", and "1 forced flash mode", the control of the exposure time of the solid-state image sensor 9 and the control of the flash light emission timing time will be explained.

FIG. 3 shows an example of the exposure time of the solid-state image sensor 9 and the timing time of flash emission. In the same figure, t
h (-2''Vh) is the exposure time limit that causes camera shake (shake limit shutter speed), and is changed according to the output of the zoom encoder, that is, the value of the focal length f of the lens.

tm (-2""X) is the highest shutter speed that can control the exposure time of the solid-state image sensor 9, and to is the above tm
It shows the divided time. In addition, =TV ta (=2 -) is the delay time from when the solid-state image sensor 9 starts exposure in response to the shutter start signal to when the flash starts emitting light, and in "flash mode", until the predetermined time ta A flash is fired after being exposed to natural light. Further, t indicates the time during which the flash is emitting light, and ts indicates the time at which proper exposure is achieved.

(1) “Natural light mode” will be explained.

The "natural light mode" is divided into three types of photographing methods, which will be explained below, depending on the brightness of the main subject.

■When the brightness of the main subject is very bright and the appropriate exposure is reached within the time of the maximum shutter speed tm.

The maximum shutter speed time tmt is exposed, and the time exceeding the time ts at which proper exposure is obtained (trr+-ts
) is overexposed, so the overexposure is corrected by reducing the gain of the photographed image in the image processing control circuit 25.

By the way, since the exposure time of t m /2 corresponds to overexposure of IEv, ts≦to (however, to=t m
/2) and tm>ts)to, the system controller 10 changes the gain correction amount and outputs it to the video processing control circuit 25. That is, when ts≦to, the excess exposure time (tm-ts) is shorter than tm/2, so constant gain=34-1. ．． Decrease OEv, t, m > t s >
1: In the case of o, the excess exposure time (tm-ts) is t
Constant gain 0.5E as it becomes longer than m/2
v is decreased.

0 When suitable exposure can be obtained in a shorter time than the camera shake limit shutter speed th.

This is a case where proper photography is performed using only normal natural light.
The photographed image is recorded by the image processing control circuit 25 without exposure correction.

■When the brightness of the main subject is dark and the appropriate exposure is reached,
When the shutter speed exceeds s or camera shake limit shutter speed th.

Camera shake limit shutter speed t to prevent camera shake
Exposure is forcibly stopped at h, and the gain of the captured image is increased by 0.5 Ev by the image processing control circuit 25 to correct the underexposure.

(2) “Dark flash mode 1 will be explained.

In the [dark flash mode], after the solid-state image sensor 9 starts exposure, the main subject in the shooting screen is
Until the time when Ev becomes a low value (this time is set as ta),
exposed by natural light, then flashed or emitted,
Exposure is stopped when the main subject becomes suitable.

This "dark flash mode" is divided into three types of shooting methods depending on the brightness of the main subject. That is, when proper exposure is reached during 079791 emission.

■When the proper exposure is reached within the camera shake limit time t after the flash fires.

(2) When the time tS at which proper exposure is reached after the flash is emitted exceeds the camera shake limit time th (this includes the case where the flash is emitted at ta=th and proper exposure cannot be obtained after the end of the light emission time tf).

In the case of (1) and (2) above, exposure is stopped when proper exposure is obtained, and the photographed image is recorded without exposure correction by the image processing control circuit 25. In the case of (2), when the camera shake limit time th has elapsed, the exposure is forcibly stopped to prevent camera shake, and the video processing control circuit 25
It is corrected by increasing the gain by 0.5Ev.

(3) “Backlight flash mode” will be explained.

In the "backlight flash mode", the time from when the solid-state image sensor 9 starts exposure to when the secondary subject in the background in the shooting screen has a higher value of IEv than the appropriate exposure (this time is set as ta)
The camera is exposed to natural light until the main subject is properly exposed, then the flash is fired, and the exposure is stopped when the main subject is properly exposed.2 In this "backlight flash mode", there are two types of photography methods depending on the brightness of the subject. That is, when proper exposure is reached during 079791 emission.

■When the proper exposure is not reached even after the flash firing time tf has elapsed after the flash fires.

In the case of ■ above, stop the exposure when the proper exposure is obtained,
The photographed video is recorded without exposure correction by the video processing control circuit 25. In the case of ■, since the object with a bright background is photographed in [backlight flash mode], the flash emission = 37 - Time ts when the main subject becomes properly exposed after the light time tf.
If the subject is exposed to light until the end of the flash, the subject will become excessively bright due to exposure to natural light after the flash has finished firing, so the exposure will be forcibly stopped after the flash firing time tf, and the exposure control circuit 25 will control the exposure of the photographed video. No corrections will be made.

Next, in the above-mentioned "backlight flash mode" and when the distance of the main subject exceeds the limit that the flash light can reach, the solid-state image sensor 9 starts exposure and then waits for the flash light emission delay time ta mentioned above. 1゜OEM added time (
Until this time is ta' - ta/2), natural light is exposed, then a flash is emitted, and after the flash is emitted, the exposure is stopped. Similar to the above-mentioned backlight flash mode j, if the time ts at which the main subject is properly exposed or the flash emission time tf is exceeded, the exposure is forcibly stopped after the flash emission time tf, and the image processing control circuit 25 Set the gain to 1. Exposure is corrected by increasing OEv.

In other words, in the "backlight flash mode" where the distance to the main subject exceeds the reachable limit of the flash light, the flash will not work effectively as auxiliary light for the main subject, so the exposure time using natural light will be ”
Shorten the exposure time to half of the exposure time with natural light and shoot so that the overall IEv is clear, then fire the flash and forcefully stop the exposure after the flash finishes, and the overall image level will be This increases the gain by IEv. In this way, the overall IEv is lowered so that the difference in brightness between the main subject and the sub-subject is smaller than the actual brightness difference, and the overall IEv is lowered at the video stage.
Since the Ev is corrected to a high value, the main subject can be photographed clearly, and the brightness balance between the main subject and the sub-subject can also be appropriately adjusted. Here, the flash emission timing time ta is the time from the start of exposure of the solid-state image sensor 9 until the flash is emitted, and is calculated by the system controller 10 based on the photometered main and sub-object brightness. It is something.

(4) “Forced light emission mode” will be explained.

In the "forced flash mode", a flash is emitted when the maximum shutter speed tm has not elapsed since the start of exposure, and the exposure is stopped when the main subject is properly exposed.

In addition, if the main subject exceeds the camera shake limit shutter speed th during the appropriate exposure time, the exposure is forcibly stopped when the camera shake limit shutter speed th elapses in order to prevent camera shake, and the underexposure is reflected in the image. The processing control circuit 25 increases the video gain by 0.5 Ev to correct it.

Next, a sequence for controlling the camera section of the system controller 10 in the electronic camera of this embodiment will be described.

First, regarding the main routine, flowchart 1 in Figure 4
This will be explained using . When the battery is first inserted into the camera, the system controller 1-roller 10 is reset to the initial state (#5), and the initial setting subroutine is executed to initialize the system controller 10 (#5).
#10). Next, in steps #15 to #30, it is checked whether the camera is in the shooting state. In other words, although the power battery is installed (#1.5m playback switch S
1 is not selected (820>), but the deck lid is not open (#25), or the deck lid is 1 open to 1 closed.
Although the status has changed, check (#30) at each step. If the battery is not inserted in each of the above steps, execute the [Battery removal] subroutine (#200). If the "playback mode" is selected, the "playback" subroutine is executed (#210). When the moss on the deck is open, click [
The recording/playback prohibition] subroutine is executed to prohibit both recording and playback operations (#220). A floppy disk for recording is inserted, and the deck is opened from the lid or open.
If the state does not change to "closed", execute the "initial load 1" subroutine, check the information on the floppy disk, and load the information into the system controller 10 (#500).

Next, check whether the main switch SO is turned on (#35). If the main switch so is OFF, shooting will not begin, so proceed to #11o, set the photographic lens 1 to the initial position, and turn off the display on the LCD display circuit 21a.#1.15) If the flash circuit If the voltage is being increased to charge HAL'F, proceed to #145, stop the voltage increase, and turn off the flash charging LED display (red) in the viewfinder (#150).
Enter the state (#160). ]-I A L'T
” state, the sequence execution of the system controller 10 is paused, and the settings of the switches 21 are checked at regular intervals to see if there are any changes (#170). If there are no changes to the settings, the HAL T state is continued and the settings are If there is a change in
Return to #15.

If the main switch SO is turned on, the same switch S
Check if it changes from OFF to ON (#40
). When the main switch so turns ON for the first time, set the "boosting required" flag to charge the flash circuit 18 (#45). If it is not the first time the main switch so turns ON, skip #45 and turn on the L CD Display circuit 2] performs the display of a (#50). In addition, L CD
In the display circuit 21a, field/frame and single/
Displays self-timer mode selection, number of shots counter, battery warning, recording mode, etc.

Next, check whether the start switch S1 of AE and AP is ON (#55). If the switch S1 is ON, it indicates that the switch S is kept pressed.
Confirm the presence or absence of the "keep pressing" flag (#60).This means that when switch S1 is pressed again, AE and AP will be performed again, and if switch S1 is held down, AE and AF will be performed again. This is because if this flag is not set, the "Sl" subroutine is executed,
Perform AE (auto exposure) and Al'' (auto focus) (#
800). If switch S1 is OFF or the "hold down" flag is set, then single/self-timer, field/frame, data 1
- Check whether there are any changes to each mode of information switching (#6
5). That is, a single/self-timer mode changeover switch S15, a field/frame mode changeover switch 311, and a date information mode changeover switch S15.
If none of the switches are kept pressed, check switches S15, S11, and S in order to see if the mode has changed (#70 to #8o).

If the single/self-timer mode selector switch S15 is ON in #70, the subroutine "1 mode change" in #23 is executed. If the date selector switch SM is ON in #75, “
Execute the "Date Change" subroutine. At #80, field/frame mode changeover switch S11 is turned on.
If so, execute the "field/frame change" subroutine of #250. If there is no change in each mode, check if the date needs to be corrected (#85). If any switch is held down, there is no mode change, so do not check each mode switch (skip #70 to #8o) and correct the date (#85).
Proceed to. If the date correction switch S is pressed, the ``date correction'' subroutine of #260 is executed. Correct the date information and then check whether flashing is necessary (#90 to #1.05). This is to set a flag in order to identify whether or not boosting the voltage for charging the flash circuit 18 is necessary depending on whether flash is necessary. If the switch S13 of "1 forced light emission in #90" is pressed, "pressure boost required J flag is set to 1 to 1 in #95" is pressed.
), if the "light emission prohibition" switch 314 is pressed in #100, the "boosting unnecessary" flag is set (#1
．． 05).

Next, check the presence or absence of the "boosting required" flag, and if it is set, start boosting the voltage if charging is not completed, and display the flash charging LED display 19b in the viewfinder.
(red) (#120~#], 35). Then, the pressure increase time is confirmed (#140), and when the pressure increase is completed within a predetermined time, the process returns to #15. Here, if the voltage increase is not completed within the predetermined time, a battery check is performed (#270). Also, check if the "boosting required" flag is not set in #120, or if #12
If charging has already been completed in step 5, #145 to #1 described above
Proceed to step 70 and enter the HALT state. Note that when each subroutine ends, the process returns to step #15(A).

Next, the "initial load" subroutine of #500 will be explained using FIG.

First, a battery check subroutine is executed to check the battery capacity (#505). Next, it is checked whether a floppy disk is inserted (#510), and if it is not inserted, the "release disabled" subroutine of #700 is executed to prohibit driving of anything other than the mirror 3 and photographing lens 1. If inserted, D C/D is used to supply power to the spindle motor 27 and video processing control circuit 25.
The C converter 12 is activated (#515).

Next, the spindle motor 27 and the video processing control circuit 25 are driven (#520), the contents written on the floppy disk 26, that is, the data of 50 tracks are read, and a map is created.
In 9b, display the track that has been uploaded to Callan I.
This indicates that the contents of the floppy disk 26 are being confirmed (#525).

Next, check whether the ``reproduction mode'' is selected with the reproduction switch S (#530), and if the ``reproduction mode J'' is selected, execute steps #535 to #545 to enter the ``reproduction mode''. In other words, check to see if there is a recording prohibition tab on the floppy disk 26 (#535); if there is no tab, recording will be prohibited, so set the "erasure prohibition" flag.
540), recording is allowed if there is a nail, so set the "erasable" flag to 1~ (#545), and #21. Proceed to the subroutine of "Reproduction mode" of O. If "Playback mode" is not selected in #530, floppy disk 2
Check whether there is a recording prohibition tab in step 6 (#550), and if there is no tab, display the “recording prohibition J” of the inserted floppy disk 26 on the LCD display circuit 19b (#555).
), the recording operation is stopped (#570). Also, if there is a claw, check to see if there are any free tracks on the floppy disk 26 #560), and if there are no free tracks, display on the LCD display circuit 19b that there are no free tracks #565). The recording operation is stopped in the same way as when there are no claws (#570). If there is an empty track, #6
Proceed to #00, move the head to an unrecorded track based on the map information obtained in #525, and then proceed to # of the main routine.
Return to 15th.

(Hereinafter, blank space) Next, “Sl” of #800, which executes AE and AP, etc.
The subroutine will be explained using FIG. “S.
1'' subroutine sequence executes AP, executes AE after focusing on the subject, prepares the flash to emit light if necessary, and enters release. First, #805 to #835 before entering the AP
Check the battery, power supply, and system controller roller 2.
3. Make preparations such as white balance. That is, when the flash circuit 18 is being boosted, the boost is stopped (#805) and a battery check is performed (#8).
10), White balance (WB) should be set to a specific color temperature for daylight #815), Solid-state image sensor 9,
In order to supply power to the video processing control circuit 25, spindle motor 27, and other circuits, start the DC/DC converter (#820), reset the system controller 23 (CPU2>#825), The temperature sensor circuit 20 is activated (#830).

Next, AF subroutine #1. , 200 (described later)
and performs a focusing operation on the subject (#835). If the focus detection result is unreliable due to low contrast and the focus is incomplete, an out-of-focus display is displayed in the viewfinder. Return to main routine #15 (#840 to #8
50). When focusing is completed in #840, check that the self-timer mode is selected (#855)
, when the self-timer mode is not selected, the spindle motor 27 is activated to drive the floppy disk 26 to prepare for recording (#860). If the self-timer mode is selected, there is no need to drive the spindle motor during the time until release, so #860
is skipped and the color temperature information of the light source is read from the color measurement information of the subject by the color temperature sensor circuit 20 (#865),
Detects whether the light source is fluorescent or tungsten light (
#870). When the light source is a fluorescent lamp or tungsten light, a "flash required" flag is set in order to emit a flash and take a picture (#875).

This is fluorescent light or tungsten light is sunlight = 5
0 - The color temperature distribution is different, and it is better to take a picture with a flash light close to sunlight, so the flash is automatically activated. If the light source is not a fluorescent lamp or tungsten light, the "photometering" subroutine of #1500, which will be described later, is executed without setting the "flash required" flag to measure the brightness of the subject (#880).

Next, when you finish metering the subject brightness in #880, #88
In steps 5 to #905, various flags are checked to confirm whether or not a flash is necessary. First, check whether the "Flash Required" flag is set (#885), and whether the flag is set or not.
Alternatively, if the flag is not set to 1 or more, or if "forced light emission mode" is selected (#8901), then check whether "light emission prohibition mode" is selected (#895).

If "Flash prohibition mode" is not selected, it is flash mode, so please check whether "Forced flash mode" in #890 is selected (#905) If it is selected,
Set the “forced flash mode” flag to Cera 1 (#910)
), check the charging state of the flash circuit 18 (#
91.5). The reason why the "forced flash mode" flag is set in #910 is to identify the fact that the flash light emission timing is different between "forced flash" and auto mode.

Next, if charging of the flash circuit 18 is completed in #915, stop boosting the voltage for charging (#920), #8
If the spindle motor 27 is not started at 60, the motor 27 is started and preparations are made for recording to the floppy disk 26 (#925), and the ED display 19a (green) indicates that the flash is fully charged in the finder. ) and do (
Proceed to #930) and #970 to check the release switch S2. If charging of the flash circuit 18 is not completed in #915, start boosting the voltage for charging #93
5), if the spindle motor 27 is started in #860, stop its driving (#940), and display the LED display 19a (red) indicating flash charging in the finder (#940).
945). Note that the reason why the spindle motor 27 is stopped in step #940 is to avoid unnecessary current consumption since there is no need to drive the spindle motor 27 during preparation for flash emission.

Next, check the status of switch S1 (#950)
, OF F-', main routine #1
Return to step 5, and if it is ON, check switch S2 (#955). If switch S2 is ON, return to main routine #15 and check the flash charging LED display 19a (red) in the finder. ) and turn it off (#9
65), proceed to #920 to #930 described above.

By the way, if "forced flash mode" is not selected in #890, the flash will not fire, so just press #
Proceeding to 970, the release switch S2 is checked. Also, the flash does not fire even when "flash prohibition mode" is selected in #895, so the flash fire is prohibited, giving priority to "forced flash" or auto mode, and #8
Change the color temperature for daylight set in #15 to #865
Based on the input colorimetric information, the temperature sensor circuit 20 changes the signal to a signal for adjusting the color balance of the photographed image and outputs it (#900), and then the process proceeds to #970.

Next, check the release switch S2 (#970), and if the switch S2 is OFF, switch so, s
i is checked (#1030 to #1035), and if either is OFF, the process returns to #15 of the main routine. If both switches 5O1S1 are ON, check whether the deck lid is open or closed (#1040). If the deck lid is closed, return to #865; if it is open, go to #22.
Executes subroutine 0 and prohibits all recording and playback operations.

If the release switch S2 is turned on in #970,
Make sure the self-timer mode is selected #9
75) If the self-timer mode is selected, the timing time for self-timer photography is counted and the light emitting element 14 is blinked (#980>, the spindle motor 27
Start up and prepare for recording on the floppy disk 26 (#985), and after 100m5 has passed, flip up the main mirror 3 and release the light shielding to the solid-state image sensor 9 (#99
0). If self-timer mode is not selected,
Skip #980 to #985 above and main mirror 3
and activates the solid-state image sensor and the video processing control circuit 25 (#995). Then, the video processing control circuit 2
Approximately 100 ms (heard when the power supply starts)
After counting (#1000), #2000 (described later)
The "release" subroutine is executed to expose the solid-state image sensor 9 (#1005). Next, the solid-state image sensor 9
After the exposure is completed, record the photographed image on the floppy disk 26 #], 010), color temperature sensor circuit 20,
The video processing control circuit 25 stops driving the solid-state image sensor 9 (#1015), and lowers the main mirror 3 (#10).
20), execute the "head feed" subroutine (specify the next track based on map information) #1025
), return to #15 of the main routine.

As explained above, in this embodiment, in order to accurately measure the brightness of the main subject and the brightness of the sub-subject in the "Sl" subroutine sequence, =55-AF is executed first to accurately measure the brightness of the subject. Metering after focusing (
AE) calculation is executed.

By doing this, in the "photometry" subroutine sequence described later based on accurate photometry data,
It is possible to classify appropriate photometry modes and calculate accurate flash firing timing. Also, in self-timer mode, to avoid unnecessary current consumption,
The spindle motor 27 is not activated until a predetermined period of time has elapsed. In addition, when using fluorescent light or tungsten light as the light source, the color temperature setting is fixed to sunlight (flash light source), so the flash is automatically emitted to take a picture, and the flash prohibition switch S14 is set. When "Light off mode" is selected, the color temperature is automatically adjusted to the color temperature of fluorescent light or tungsten light (AWB).
I try to do that.

Next, the rAF subroutine of #1200 (#835 above) for executing the AP will be explained using FIG.

First, turn on the power to the focus detection sensor 7 (CCD line sensor #1205), then discharge unnecessary charges accumulated in the focus detection sensor and set it to the initial state (#1
210), start charge accumulation of the focus detection sensor (#1
．． 215>. Thereafter, the system waits until the interleaved signal lNTl that indicates the end time of charge accumulation in the focus detection sensor is input (#1220), and the interleaved signal lN
When Tl is detected (#1.225), the focus detection sensor 7
The accumulated charge is transferred to an analog shift register, and the accumulated charge is output from the shift register one pixel at a time, and the A/D
The converted data is sequentially input to the system controller 1-0 (#1230>).

Next, the system controller 10 detects the defocus scale from the data imported #1235) and determines the reliability of the defocus scale #1.240)
If the image is unreliable due to low contrast, a "low contrast" processing subroutine is executed (#1325), an out-of-focus display is displayed (#1330), and the process returns to the main routine (#1320). If the subject is not unreliable due to low contrast, check whether the subject is accurately focused #1.245), and if it is, check the information of the previous stop position of the photographing lens 1 and the current movement. Information on the current stop position is obtained from the amount information, and based on this information, the shooting distance is calculated using a conversion coefficient according to the focal length f at that time, and this shooting distance and focal length f
Calculate the shooting magnification β (#1305). and,
The focus LED 19a (green) in the finder is displayed (#1310), the clutch circuit 13 is turned off, and the motor M
Switch the connection from shooting lens 1 to main mirror 3 (
#1315), return to the main routine (#13
20). Also, if it is not in focus at #1.245,
Follow the steps below to focus.

First, the lens extension electric conversion coefficient K is read from the ROM in the system controller 1o based on the current focal length f from the zoom encoder switch S12 (#1250
), the defocus scale is multiplied by the conversion coefficient K to obtain the number of pulses N (= KX
Find D) (#1255). Next, the calculated number of pulses N
into the "counter" in the system controller that monitors the rotation amount of the motor (#1260), and clutch circuit 1
3 is turned on, the connection to the motor is switched from the main mirror 3 to the photographing lens 1 (#1265), and the driving of the photographing lens 1 is started (#1270).

Next, make it interruptible by the "counter"#
1275), wait until the counter value becomes -0 and a counter interrupt occurs #1280), and when a counter interrupt occurs (#1-285) = Stop driving the photographic lens 1 and focus (#1-285) #1290). Then, in order to confirm the in-focus state, charge accumulation in the focus detection sensor 7 is started again (#1.295>), and waits until the interlab 1 signal lNTl is input (#1300).
Thereafter, the process returns to #1.225 and focus confirmation processing is performed.

If the focus is incomplete during the focus confirmation process, try again #124
5 to #1250, and #1250 to # until focus is achieved.
Repeat the routine of 1300.

Next, the photometry J subroutine of #1500 (#880 above) will be explained using FIG. 8(a).
In the figure, the unit used for calculation is the APEX value.

First, calculate the ISO sensitivity correction, that is, calculate the corrected ISO sensitivity Sv (=Svo7γ) from the standard ISO sensitivity Svo of the solid-state image sensor 9 and the imaging sensitivity variation correction amount γ #150B>, then av1 Optical sensors 17a, 17
b starts measuring the brightness Bv1 (spora 1 to photometric value) at the center of the photographic screen and the brightness Bv2 (average photometric value) around the photographic screen (#1505). Next, the analog signal of the luminance measured by the photometric sensors 17a and 17b is started to be converted into a digital signal by the double integration circuit 22g. Please check #1515
), if it is not completed, wait until it is completed, and when it is completed, input the photometric data converted into a digital signal to the system controller 10 (#1520).

Next, check whether AF-AE lock is completed (#
1525). If AF-AE or Gf is not locked,
Execute steps #1530 to #1545 to obtain the brightness difference ΔBv between the peripheral brightness Bv2 and the center brightness Bvl and the main subject brightness Bvs. In other words, check whether it exceeds Bvl or 11#
1530), ]1, the central brightness is too high and should be identified as Bvl-11.
Calculate the brightness difference ΔBv-Bv2-B■1 between the central brightness Bvl and the central brightness Bvl (#1540), then subtract the correction amount α shown in Table 1 from the central brightness BV1 to obtain the main subject brightness Bvs (=
Bvl-α) is calculated (#1, 545). AP-A
When E is locked, the brightness difference ΔBv and the main subject brightness Bvs have already been determined, so #1.5
Skip steps 30 to #1545 and proceed to #1550, which will be described later. Note that AP-AE first performs photometry (AE) after switch S1 is closed (#55) in the main routine.
＞When entering the calculation subroutine (subroutine “
Enter #1500 at #880 of "Sl"), proceed directly from #1525 to #1530 without locking, return to #865 from #1040 of subroutine "Sl", and enter #1525 from #880 again. Sometimes it is locked for the first time.

Next, check whether the peripheral brightness exceeds Bv2 or 10.#
1550), if it exceeds Bv2 or 10, the peripheral brightness is too high, so fix Bv2 = 1.0 #1555)
, 10 or less, Bv2 is directly used as the sub-subject brightness Bva (#1560). Next, the central brightness Bv
1. Check whether the brightness is low to the photometric limit value of photometry sensor 1, 7a #1.565), and if the brightness is low to the photometry limit value, use the average of the entire shooting screen for low brightness processing. Calculate the brightness BvS' using the following formula #1595), #160
Go to 0. That is, Bvs 7°Bva B v s '= -+ -□ If the brightness is not low, calculate the reference value δ for backlight judgment from Table 2 and Bvs (#1570), and then calculate the secondary subject brightness Bva and the main subject brightness. Bvs brightness difference ΔBv' (-Bva-B
vs) and the judgment reference value δ obtained in #1.570 (#1575). Here, if ΔBv'>δ, it is determined that it is backlight and the flag ``Set the backlight -j'' is displayed.8158
Set the average brightness Bvs' for 0m backlight processing to Bvs (#1590), proceed to #1600, and find that ΔBv'≦δ
If so, it is judged as "frontlight", and the average brightness 13 v s' for frontlight processing is calculated using the following formula (#1.58
5), proceed to $1600.

Bvs 3−Bva B v s ′= −−−−−1−□−−−Next, #
1.600~#16 ]-5 to determine the shooting mode. First, check if the "backlight" flag is set (#1600), and if the flag is not set (in the case of "frontlight mode"), check #1585 or #15.
Compare the average brightness Bvs' of the entire shooting screen obtained in step 95 with the camera shake limit brightness Bvh, and classify the modes into "flash mode" and "natural light mode"(#1605).
If Bvs'≧Bvh, then it is determined whether the flushing necessary flag is set (#1606
). Here, if the flag is set, it indicates that the illumination light source is not sunlight but artificial light such as a fluorescent lamp or tungsten light, and that the cellar 1~ was set in #875 in Fig. 6. Proceed to routine 2 of "dark flash mode". On the other hand, if the flag has not been set, the process advances to #1.620 of the "natural light mode" routine (2). Bvs
If '<Bvh, proceed to #1675'\ of the [dark flash mode] routine ■. If the "backlight" flag is set (in the case of "backlight"), the sub-subject brightness B
Brightness (BVa-δ
) and camera shake limit brightness B v h #1610)
, if (Bva-δ)≧Bvh, set the "transparent" flag indicating backlight on a bright background (#1615
), #180 of [Backlight Flash Mode] Routine ■
Proceed to Q. If (Bva-δ) < Bv) 1, it means backlighting in a dark background, so the process proceeds to #1675 of the "dark flash mode" routine (2).

Next, the "natural light mode" will be explained.

First, check whether the "forced flash" flag is set (#], 620). If the flag is not set, then check whether the "transparent" flag is set (#1625), " If the "transparent" flag is not set, set the average brightness Bvs' to the control Bv value Bvt (#1630), and set the correction amount ΔE v h when measuring the main subject brightness to the left to zero (#163).
5) If the "transparent" flag is set in #1625, the background is brightly backlit, so the control Bv value Bvt
Set the main subject brightness Bvs by +0.5, that is, Bvt = Bvs + 0.5 (#1640), and set the correction amount ΔE v h j to (0,5 - (Z)) (#1645). ). Note that α is the correction amount shown in Table 1, and its value changes depending on the imaging magnification β.

Next, control Bv value Bvt and minimum brightness Bv that can be photographed
Compare #1650), if Bvt≦Bvj, the shooting screen will be dark, so set the "shooting not possible" flag to Cera 1.
to #1660), displays in the viewfinder that photography is not allowed (#1665), executes the "Release Lock" subroutine and prohibits photography (#1670), Bvt>
If Bv and Q exist, set the flash unnecessary flag #1655) and return to the main routine (#17
95).

Further, if the "forced flash" flag is set in #1620, then the flash mode is in effect, and the process proceeds to #1675 of the "dark flash mode" routine (2).

Next, the "dark flash mode" routine (3) will be explained.

First, check to see if the "flash prohibition" flag is set (#1675); if the flag is set, the process proceeds to #1625 of the "natural light mode" routine (2), since the photograph is being taken using natural light. If the flag is not set to 1~, the brightness (Bv
s+1. ) and camera shake limit brightness f3 v h #1.680), and change the setting of the control Bv value depending on the brightness of the main subject brightness. That is, Bvs+1≧
13 v h, set the control Bv value Bvt to the brightness (Bvs+1) obtained by correcting the main subject brightness Bvs by +1°0 (#1685), and if Bvs+1<Bvh,
Since the main subject brightness is lower than the camera shake limit brightness, control B
The v value Bvt is fixed at camera shake limit brightness 13 v h (
#], 690).

Next, the correction amount ΔEvf of the exposure amount due to flash emission
, the 1-series K added to Q is set to 0 (#1695), the value of the photographing magnification β is classified into three types (#1700), and the amount of correction Δ of the exposure amount due to flash emission is calculated for each of the three types (#1700).
Set Evf and Q (#1705 to #i, 71.5
). In other words, if β〉 1/25), Complement 1 "Set the amount ΔEvf to 0 #1705), (1/2
5) If ≧β>(1155), the correction amount ΔEvf
Set to (0,5-K) #1710), (
1155) If ≧β, set the exposure amount correction amount ΔEvf due to flash emission to (1,0-K) (#1
715).

This is to correct for the fact that the size of the main subject on the photographic screen changes depending on the imaging magnification β, and the amount of exposure due to flash emission also changes.

Next, the above correction amount ΔE is added to the maximum light emission amount Iv of the flash.
The amount of flash light emitted by adding vfj ■v′ (=Tv
+ΔEvf, Q ), and further calculates the aperture value A v d from the above ■■', film sensitivity Sv, and subject distance information Dv using the following equation (#1720). That is, Avd2Iv'+5v-Dv = Iv+Sv-Dv-to ΔEvfNext, compare the aperture value Avd obtained in #1720 with the aperture value Avoz corresponding to the focal length at that time, and find out whether the distance of the subject is close to the flash. Determine whether the light exceeds the reachable limit (#
1725). If A v d > A VOZ, a "far range" warning is issued (#1730) indicating that the distance to the subject exceeds the limit that the flash light can reach, and the "far range" flag is also set. 1 to (#1735), and set the aperture value A v d to Avoz (#1740).
If Avd≦Avoz, do nothing.
Set the aperture value Avd to Avoz (#174.0>.

Next, the brightness B v m (= T' v m + A
v d -8v) and #1685 or #1.690
Compare the control Bv value Bvt set in #1745
), if Bvt≦Bvm, the process directly proceeds to #1765, and the flash light emission timing time -1'v is calculated using the above-mentioned limit Bv value +3vt. Bvt>
If it is Bvm, check whether the "Open" flag is set (#1750), if the flag is not set, proceed to #1765, and if the flag is set,
Control wBv value Bvt ('I" v m-t-A v d
-8v) (#1755), and set the main subject brightness B
Control BV value Bvt (=T
vm + Avd - 3v) = 69- (#1760), if Bvs≦Bvt, then #176
5, the flash light emission timing time Tv is calculated using the control Bv value Bvt set in #1755. If B v s > B v t, the process advances to #1620 of the "natural light mode" routine (■). In addition, #1
765, the flash emission timing time T”
v is calculated from the following formula.

E v = B v t + S v T v = Ev - A v d = B v t + S v - A v d Next, #1
Compare the flash timing time Tv calculated in #1770.765 with the maximum shutter speed Tvm or camera shake limit shutter speed Tvh. #17
80), if Tv≧T v m, it is the time when flash emission cannot be controlled, so set the timing time Tv to the maximum shutter speed T v m (#], 775
>, if Tv≦T v h, there is a risk of camera shake before the flash fires, so set the timing time Tv to the camera shake limit shutter speed T v h (#1785), and select "Flash required". Set the flag #1.790) and return to the main routine (#1795).If Tvh<Tv<T'vm, then (
#1770, #1780), #1765] ■
Using , proceed to #1790 to #1795.

Next, the routine (2) of the [backlight flash mode] will be explained.

First, check whether the "1 flash prohibited" flag is set to Cera 1~ (#1800), and if the flag is set, "
Proceed to #1625 of routine ``Natural Light Mode''. If the "1 flash prohibition" flag is not set, control Bv
The value Bvt is calculated from the sub-subject brightness Bva by a correction amount of 1. Set the value minus OEv, that is, Bvt = Bva-1, 0 #1805), the above control Bv value Bvt and main subject brightness B
The brightness difference from vS, that is, the brightness difference from the appropriate natural light component ΔEv n (= B v s - B v t
) should be calculated #1810), the above luminance difference ΔEvn and -1
Compare ゜0Ev (#1815), ΔEvn>--7
1,-,,-1,0, fix ΔEvn to -1,0 and control B
Set the v value Bvt to the value obtained by adding the correction amount 1 and OEv to the main subject brightness Bvs, that is, Bvt = Bvs + 1.0,
If ΔEvn≦-1,0, #1805 and #181
Set at 0 and bend vt=Bvs+1.0 and ΔEvn=Bv
Use s-Bvt.

Then, the correction amount ΔEvf of the exposure amount due to flash emission
, set the coefficient K added to Q to the value of α #1825
), proceed to #1700 above, [Dark flash mode]
Processing from #1700 described in .

By the way, in the "backlight flash mode", the predetermined timing time '1'V of flash emission is calculated from the brightness of the sub-subject (however, when δ≦Bv≦2, the timing time of flash emission is calculated from the main subject brightness). After the start of exposure, the flash is emitted after a predetermined time period of 1゛■ has elapsed, and the exposure is stopped when the main subject is properly exposed, thereby adjusting the balance of brightness between the main subject and the secondary subject in the background. In this example, the exposure is stopped when the flash is fired and the main subject becomes proper, so the main subject becomes proper, or the sub-subject is overexposed by the amount of time the flash fires. Become.

Therefore, in addition to the above-mentioned embodiment, a second embodiment will be described below, which can accurately adjust the balance of brightness between the main subject and the sub-subject. That is, a fixed correction time X [seconds] is calculated from the luminance difference between the main subject and the sub-subject, and the flash is emitted before the predetermined time Tv elapses.

If the value obtained by converting the above predetermined time "I" v into units of [seconds] is X'', and the timing time of flash emission corrected from the same x'' by the fixed time X is x' (seconds), then x''=2''
ゞ [seconds] x'-X''-X [seconds] T v pa x' = 2 - x [: seconds] x' is the timing time of flash emission.

8 (l
]) will be explained using a flowchart.

The flowchart in FIG. 8(b) is inserted between #1765 and #1.770 in FIG. 8(a).

First, in #1765, the flash emission timing time Tv is set.
After calculating, check whether the "open" flag is set to 1~ (#1895), and if it is not set, proceed directly to #1770. If the flag is set, a correction amount ΔEvf from the appropriate amount of flash light is calculated from the luminance difference ΔEvn from the appropriate amount of natural light using the following equation (#1900).

ΔEvn) ΔE v f = I o g 2 (1-2nd order,
The required flash emission amount 1vs is calculated from the main subject distance using the following formula (#1905).

I v s = A v o Z + I) v −S
vNext, the flash light emission amount Ivs determined in #1905
Compare the actual luminescence amount Iv with #1910), Ivs≦
If Iv, calculate the correction amount ΔEvf' obtained from the distance information obtained from the main subject distance and the appropriate correction amount ΔEvf for the flash light amount from the following formula #1915),
A correction time X corresponding to the correction amount ΔEvf' is determined from the table shown in Table 4 (#1940).

ΔEvf'=Ivs-Iv+ΔEvf Also, if I vs>I v, calculate the uncorrected light emission 11vs' (=Ivs+ΔEvf) by adding the brightness difference correction amount ΔEvf to the flash light emission amount 1vs. #1.
920), and calculates the correction amount ΔEvf' from the difference between this light emission amount Ivs' and the actual light emission amount 1v (#192
5). That is, ΔEvf'=Ivs'-Iv Next, check whether the above correction amount ΔEvf' is less than or equal to OEv (#1.930). If ΔEvf'>O, then ΔEv
Set f' to O (#19035), and if ΔEvf'≦0, use the same ΔEvf', #1.94
0, and calculate the correction amount ΔEvf' from the table shown in Table 3.
Determine the correction time corresponding to

Next, from the X obtained in #1.940 and the above predetermined time] ゛■, the flash emission timing time x' is determined by the following formula.
C seconds] (#1945).

x'-2-TV-X Next, convert the flash emission timing time X' [seconds] into Tv (Ev:] using the following formula, and proceed to #1770 (
#1950).

T v = log 2 (1/ explain.

The "Release" subroutine is composed of routines for "Natural Light Mode", "Flash Mode", and "Forced Light Mode".

First, switch the switch SWI to designate the photometry sensor as the light receiving section 17a (spot photometry at the center of the shooting screen) (#
2005). This is to control the exposure of the solid-state image sensor 9 to be stopped at a suitable point for the main subject, so that the sensor for photometry is set to spot photometry at the center of the photographic screen. Next, in #2010 and #2015, the shooting mode is divided into "natural light mode", "flash mode", and [forced flash -76= mode]. If the "forced flash" flag is set in #2010, the process advances to the "forced flash mode" routine in #2235 to #2275 (described later), and in #2015, the "forced flash" flag is set.
If the “Flash Required” flag is set, #20
The program proceeds to the "flash mode" routine from #90 to #2230 (described later), and if the "flash required" flag is not set to "1 natural light mode" from #2020 to #2085.

When shooting in natural light mode (#2020), first, the ISO feeling is corrected by the main subject brightness correction value ΔEvh and the image pickup sensitivity variation correction value γ (#2025). Next, timer T I and timer T2 are respectively set to the two-divided value to of the maximum shutter speed t m (-2T v m ) and the camera shake limit shutter speed th - T v h (=2), and a countdown is started. At the same time, the exposure of the solid-state image sensor 9 is also started (#2030). Next, time t.

It is confirmed whether the exposure amount of the solid-state image sensor 9 has reached an appropriate level by the time the solid-state imaging device 9 has passed. That is, timer T1-0-77
= 120.35), T1. >O, compare the voltage value (hereinafter referred to as exposure voltage value) of the capacitor C of the circuit 22i that detects that the amount of charge accumulation in the solid-state image sensor 9 has become appropriate with the reference voltage value Vo.# 2040)
, if Vo<V, the charge accumulation amount has not reached the appropriate value, so return to #2035, check timer T1- again, and if Vo≧■, the charge accumulation amount has reached the appropriate value. , Since charge accumulation is carried out excessively until time tm, a flag is set to correct the gain of the photographed image by -1 or 0 (#2045), and the process proceeds to #2280 to #2290.
The shutter is closed, the gain correction value -1°0 is output to the video processing control circuit 25, and the process returns to the main routine.

If 'I' 1 = O in #2035, timer T1
To is set again to start a countdown, and it is further confirmed whether the exposure amount of the solid-state image sensor 9 reaches an appropriate level by the time the time to has elapsed (#2250 to #2060).

If the solid-state image sensor 9 reaches the proper exposure before the time to has elapsed, charge accumulation will be excessive until the time tm, so a flag is set to correct the gain of the captured image by -0.5 ( #2045), #2280 to #2290
The process proceeds to , closes the shutter, outputs the gain correction value -0, 5 to the video processing control circuit 25, and returns to the main routine. If the solid-state image sensor 9 does not reach the appropriate exposure by the time to has elapsed (T 1. = O in #2055)
), then confirm whether the solid-state image sensor 9 reaches proper exposure between times tm and th (#2070, #2075>.

In other words, if Vo≧■ (#2070), the solid-state image sensor 9 has reached the appropriate exposure, so the shutter is closed (#2
280>, since there is no gain correction, a gain correction value of 0 is output to the video processing control circuit 25 (#2285), and the process returns to the main routine (#2290). If V o <■, check whether T2=O (time th has elapsed) #2075) If T2=O, the exposure time of the solid-state image sensor 9 or the camera shake limit time has been exceeded, so Stop the charge accumulation in the solid-state image sensor 9 (#2080), set a flag to correct the gain of the captured image by +0.5 to compensate for the underexposure (#2085), and close the shutter (#2085). 2280), outputs the gain correction value +0.5 to the video processing control circuit 25 (#2285), and returns to the main routine l (#2280).
2290).

Next, to explain the flash mode (#2090), similarly to the natural light mode, first, the correction value ΔEvf, Q of the main subject brightness and the ISO sensitivity Sv corrected by the image pickup sensitivity variation correction value γ are D/A. It is output to the conversion circuit 22h (#2095). Next, check if the "backlight" flag is set in #2100>. If the flag is set, proceed to #2155-82230 for "backlight" flash mode shooting (described later); if it is not set, , #2105 to #2150 normal flash mode photography is performed. In normal flash mode photography,
The flash emission timing time ta (=2-T v > and camera shake limit shutter speed th) are set in the timer 'f'1 and timer T2, respectively, and at the same time the timers TI and T2 start counting, the solid-state image sensor 9 is exposed. Also start (#2105>. Next, "r'1=o(
Exposure with natural light is performed until the elapse of time ta),
When T1-〇 is reached, fire the flash (#21
10 to #2115), and at the same time, sets the flash emission time tf to timer T3 and starts counting down (#2120>. While the flash is firing (T
3>O), compare the reference voltage value Vo and the exposure voltage value ■, and
If O≧■ (#2] 25 to #2130), the solid-state image sensor 9 has reached the appropriate exposure, so #2280 to #229
0, the shutter is closed, and since there is no gain correction, the gain correction value O is output to the video processing control circuit 25, and the process returns to the main routine.

Next, if V o < V and proper exposure is not achieved during flash emission, the solid-state image sensor 9 will reach proper exposure before camera shake limit time th has elapsed (T 2 = O) after flash emission (after time tf has elapsed). Check if it reaches (#2
135~#2140). Once the proper exposure is reached, (#21
40), proceed to #St-2280 to #2290 in the same way as #2130, close the shutter, and set the gain correction value 0 to the video processing control circuit 25 since there is no gain correction.
and return to the main routine. If proper exposure is not reached by the time the camera shake limit time th has elapsed (1゛2-〇), the charge accumulation in the solid-state image sensor 9 will be forcibly stopped when the time th has elapsed (#2145). Set a flag to correct the gain of the captured image by +0.5 to correct the underexposure (#2150), and #2280
~Proceed to #2290, close the shutter, and set the gain correction value +
0.5 is output to the video processing control circuit FRt25, and the process returns to the main routine.

Next, the "backlight" flag is set in #2100, and when shooting in "backlight" flash mode, the "backlight" flag is set.
Please check if the “Quick generation” flag is set #2155
), if the flag is not set, set the flash emission timing ta in timer T #21
．． 60), when the flag is set, timer T
The timing time ta' (=ta/
2) is performed from cell 1 to (#2195>), a countdown is started, and at the same time, exposure of the solid-state image sensor 9 is also started.

If the "remote" flag is not set and the flash emission timing time ta has not elapsed (#2165
>, the flash is emitted (#2170), and at the same time, timer 1 is set to the flash emission time tf, and a countdown is started (#2175). Then, when the solid-state image sensor 9 reaches proper exposure (#2180, #21.90) during flash emission ("r"> 0), #2280~
Proceeding to #2290, the shutter is closed, and since there is no gain correction, the gain correction value O is output to the video processing control circuit 25, and the process returns to the main routine. If proper exposure is not achieved while the flash is firing, after the flash fires (time tf
), forcefully stop the charge accumulation in the solid-state image sensor 9 (#2185), close the shutter without setting the gain correction flag for the captured image (#2280),
Since there is no gain correction, a gain correction value of 0 is output to the video processing control circuit 25 (#2285), and the process returns to the main routine (#2290>. #2160 to #2185
When shooting in the "backlight flash mode", the background is brightly backlit, so even if the exposure is forcibly stopped at 85, no gain correction is performed on the captured image.

Even if the "remote" flag is set to ``remote'', the flash is fired after the flash emission timing time ta' has elapsed, and the solid state is When the exposure of the first image element 9 reaches the proper exposure, the shutter is closed, and since there is no gain correction, a gain correction value of 0 is output to the image processing control circuit 25.
Return to main routine <2200~#2220
．． #2280-#2290). If proper exposure is not obtained during flash emission, the charge accumulation in the solid-state image sensor 9 is forcibly stopped after the flash emission #2145), and a flag is set to correct the gain of the captured image by +1.0 (#2145). #2230), closes the shutter (#2280), outputs the gain correction value +1.0 to the video processing control circuit 25 (#2285), and returns to the main routine (#22).
90).

#2195 to #2230 "Remote""backlight flash mode" shooting uses natural light exposure time to half the time ta when shooting "backlight flash mode", so #2225 forces the exposure. When stopped, the gain correction of the captured video is +1°0.

Next, the forced flash mode (#2235) will be explained. First, the main subject brightness correction value ΔEvf" and the ISO sensitivity Sv corrected by the imaging sensitivity variation correction value r are output to the D/A conversion circuit 22h. (#2240). Next, the maximum shutter speed tm and camera shake limit shutter speed th are set in the timers T1 and 1 and 2, respectively, and at the same time as the timer TI T2 starts counting, the exposure of the solid-state image sensor 9 is also started (#2245).
). Next, when the maximum shutter speed tm has elapsed (
'T'1 = 0), use the flash #2250~#
2255), camera shake limit time t h has elapsed ('I')
2=O), it is confirmed whether the solid-state imaging element 9 reaches the appropriate exposure (#2260 to #2265). Camera shake limit time t
If the proper exposure is reached within h hours, the shutter is closed (#2280), and since there is no gain correction, a gain correction value of 0 is output to the video processing control circuit 25 (#2285>,
Return to the main routine (#2290). If the proper exposure is not reached, when the camera shake limit time th has elapsed (when T2=O), the charge accumulation in the solid-state image sensor 9 will be forcibly stopped (#2270), and the image will be taken to correct the insufficient exposure. Set the flag to correct the video gain by +0.5 #2275> and close the shutter (#2280
), outputs the gain correction value +0.5 to the video processing control circuit 25 (#2285>, and returns to the main routine (#2290).

This concludes the explanation of the release sequence operation.

In this embodiment, in order to downsize and reduce the cost of the device, the flash light emission stop circuit is omitted so that the flash always emits full light.

-86~ However, in order to save power, the flash may also stop emitting light when the exposure is stopped.

(Hereinafter, blank space) Table 1 Note) [Main]: Main subject brightness, Bvs': Average brightness value of the shooting screen - 87 = Table 3-1 88 - Table 4 [Effects of the invention] As described above, the present invention According to , the flash is automatically fired when the color temperature of the detected subject differs from that of sunlight (daylight), so the white balance circuit that corrects color reproduction is fixed to daylight. It is a good idea to do this in advance, and the circuit configuration can be simplified.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of an optical system of an electronic camera according to an embodiment of the present invention, FIG. 2 is a system configuration diagram of the electronic camera, and FIG. 3 is a time diagram for explaining exposure time and flash emission timing. 4 is a flowchart of the main program that controls the camera section of the electronic camera, FIG. 5 is a flowchart for executing the initial load applied to the main program, and FIG. A flowchart executed when the applied switch S1 is turned on, FIG. 7 is a flowchart for executing AF applied to the flowchart of S1, and FIG. 8(a) is a photometry applied to the above flowchart. A flowchart for executing the AE calculation, FIG. 8(b) is a flowchart for explaining a second embodiment of the flash emission timing according to the present invention, and FIG. 9 is a flowchart applied to the flowchart of S1 above. 3 is a flowchart for executing a release. 10.23... System controller, 18... Flash circuit, 20... Color temperature sensor circuit, 22...
- Control IC525...Video processing control circuit.

Claims (1)

[Claims] (1) A means for detecting the color temperature of a subject and outputting information regarding the color temperature, and determining whether or not the color temperature of the light source illuminating the subject is daylight based on this color temperature information. When it is determined that the means and color temperature are different from daylight,
1. An imaging device equipped with a color temperature detection device, comprising: means for outputting a flash light instruction signal; and a color temperature detection device.