JPH02161877A - Electronic still camera - Google Patents

Abstract

PURPOSE:To reduce the load of a power supply and to give no influence to the operations of a video circuit and a recording system as well as the operation of an auto-focus mechanism by controlling the drive of the auto-focus mechanism and the drive of the recording system of a spindle motor, etc., in the prescribed sequence. CONSTITUTION:When a focusing action is through with use of an auto-focus mechanism, either one or both of the power supplies of a recording medium drive mechanism and a video process circuit are turned on. Therefore the power supply of the drive mechanism of a recording medium like a floppy disk, etc., and the power supply of the video process circuit are turned on when a focus control action is over with use of the auto-focus mechanism. Thus both the auto-focus mechanism and the drive mechanism of the recording medium are never driven at one time. Then the power voltage produce no large fluctuation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to sequence control of an electronic still camera equipped with an autofocus mechanism.

[Prior Art] Generally, in an electronic camera using a solid-state image sensor such as a COD, a signal from the image sensor is recorded in a video circuit as a video signal on a recording medium such as a magnetic disk.

By the way, after turning on the power, the spindle motor for rotating this magnetic disk (floppy disk)
It will take some time for the rotation speed to stabilize. Therefore, it has conventionally been known to appropriately perform sequence control regarding the drive of the spindle motor in relation to turning on the photometry/distance measurement switch and the release switch.

For example, in Japanese Patent Application Laid-open No. 60-219673, photometry and
The spindle motor is started when the distance measuring switch is turned on, and the COD exposure operation is started when the release switch is turned on, but exposure is prohibited until the rotational speed of the spindle motor is stabilized.

Also, Japanese Patent Application Laid-Open No. 60-29096, U.S. Patent No. 4,
No. 692.815 discloses a device in which the accumulated charge is vertically transferred from the CCD after the rotational speed of the spindle motor becomes stable, and the recording operation is started.

[Problem M to be solved by the invention] By the way, in electronic cameras that are equipped with an autofocus mechanism that focuses the photographic lens,
A considerable amount of drive current is required to drive the photographic lens. Therefore, for example, if the photographing lens is also driven when the spindle motor is driven, there will be a heavy burden on the power supply and voltage fluctuations will occur, which may adversely affect the servo drive system of the floppy disk by the spindle motor, or Fluctuations in the power supply voltage caused by driving the lens may have an adverse effect on the state of the video circuit.

The present invention solves the above problems by controlling the driving of an autofocus mechanism and the driving of a recording system such as a spindle motor in a predetermined sequence, thereby reducing the burden on the power supply and reducing the burden on the video circuit and recording system. It is an object of the present invention to provide an electronic still camera that does not affect the operation of the camera and the operation of an autofocus mechanism in any way.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides an imaging means, a video processing circuit for recording a signal from the imaging means as a video signal on a recording medium, and a video processing circuit for driving the recording medium. In an electronic still camera equipped with a drive i-ellipse to drive the photographing lens into focus, and an autofocus II structure to drive the photographing lens to a focused state, after the focusing operation by the autofocus timing is completed, the power supply of the drive mechanism of the recording medium and the image processing circuit are The device is designed to turn on one or both of the power supplies.

[Function] According to the above configuration, after the focus adjustment operation by the autofocus 81 is completed, the power to the drive mechanism of the recording medium such as a floppy disk and the power to the video processing circuit are turned on. Therefore, both the autofocus i structure and the recording medium drive R structure are not driven at the same time, and large fluctuations in the power supply voltage do not occur.

[Effect of the invention] According to the present invention, the following effects can be obtained.

(1) It is possible to prevent power fluctuations caused by the drive current of a recording medium drive system such as a spindle motor during the focus detection operation using the autofocus wU horizontally.

(2) When driving the photographic lens, the drive current of the recording medium drive system is no longer superimposed on this drive current, which reduces the burden on the power supply, especially at low temperatures when using batteries. This allows you to increase the number of shots you can take.

(3) If the photographic lens moves when the recording medium drive system is driven,
Fluctuations in the power supply voltage may occur, which may cause the servo of a recording system such as a floppy disk to come off, but according to the present invention, the photographing lens does not move when the recording medium drive system is driven, and the servo of the recording system comes off. Things will go away.

(4) There is no possibility that the power supply of the video processing circuit will fluctuate due to fluctuations in the power supply due to driving the photographing lens, thereby affecting the performance of the video processing circuit.

(Hereinafter, blank space) [Example] A configuration diagram of an optical system according to an embodiment of the present invention is shown in Fig. 1. In the figure, 1 is a photographic lens including a zoom lens, and 2 is a photographic lens that passes through the photographic lens 1. A half mirror 13 with a low reflectance that guides a part of the light to the photometric sensor 6 has a half mirror only in the center and a total reflection mirror around the center, and a main mirror 4 that guides the light transmitted through the mirror 2 to the pentaprism 5. 5 is a sub-mirror that totally reflects the light transmitted 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 low-pass filter. , 9 are solid-state image sensing devices (for example, C0D) arranged in a matrix having a shadow function.

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. Further, the sensor 6 is located at a position where the distance 11Rb between the reflection point A of the half mirror 2 and the photometric point B of the sensor 6 and the distance MRC from the reflection point A to the imaging point C of the solid-state image sensor 9 are equal. It is arranged so as to be equivalent to performing photometry on the imaging surface of a solid-state image sensor: f-9. Further, the sensor 6 is placed in a position where the received light is not blocked regardless of whether the main mirror 3 is up or down.
Even when the solid-state image sensor 9 is exposed to light when the mirror is raised, photometry can be performed at the same time.

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 overseas system controller calculates the defocus l based on the output of the focus detection sensor 7,
Based on this! Drive the lv lens 1 to focus.

After the object is completely focused, the photometric sensor 6 measures the brightness of the object, and based on the brightness information, the system controller determines the charge accumulation time of the solid-state image sensor 9 (
That is, the shutter open 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 up, the sub-mirror 4 is folded, and exposure to the solid-state image sensor 9 is started. That is, the solid-state image sensor 9 starts accumulating charges. Further, the photometric sensor 6 starts photometry at the same time as the charge accumulation in the solid-state image sensor 9, and when it is detected that the amount of photometry has reached the appropriate exposure value, it stops the charge accumulation in the solid-state image sensor 9, and The accumulated charge is transferred to the analog memory section and the photographing is completed.

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 has been removed to make the camera more compact and to simplify the mechanism. For this reason, 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 protect against high-brightness objects 11 (for example, the sun). By forming an image or being exposed to light for a long period of time, the color filter (not shown) provided on the front side of the image pickup element 9 is prevented from fading (burning), and the solid-state image pickup element 9 is not required except for the time of release. This prevents excessive charge accumulation.

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

In the figure, 10 is a system controller (CPUI) that controls the sequence of the entire camera section, and 23
11 is a system controller (CPtJ2) that controls the sequence of the video section, and 11 is a focus detection C that drives the lens and automatically focuses (AF).
A control circuit block consisting of the CD line sensor center face circuit, and a system controller!・Roller 10
This is because the AF station controls the charge accumulation function and the function of sequentially A/D converting and outputting the accumulated charges. Further, 12 is an I) C/DC converter that generates different power supply voltages for each circuit block and supplies power, and 13 is an I) C/DC converter for switching the power of the motor M to the photographing lens 1, main mirror 3, and sub mirror 4. Clutch circuit 14 is an AF auxiliary light source (1, ED) to add contrast between light and dark to dark objects where distance measurement is not possible, and to enable distance measurement, and an LED that flashes while the self-timer is operating. A driving IC 516 for driving the motor M is a photocoupler that generates a number of pulses corresponding to the driving amount of the photographing lens. Reference numeral 17 denotes a photometric sensor, which includes a sensor 17a that measures the brightness at the center of the photographic screen in a sub-volume manner, and a sensor 17b that measures the brightness around the photographic screen except for the center. Also, 18 is a fludge, 1 circuit, and 19 is in the finder! -ED display circuit 19a and 1-7CD display circuit 1 on top of camera body
9b is a display circuit, 2o is a color temperature sensor circuit for measuring the color temperature of a light source illuminating the subject, and 21 is a switch including a switch linked to a shutter button and a mode changeover switch.

Here, each switch of the switches 21 is shown. SO is the main switch for prohibiting camera operation when "open", and SL starts AE (auto exposure) and AF (auto focusing). S2 is a release start switch.

33, S4 sets a correction amount according to variations in the imaging sensitivity (i.e., 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, at the 3ia stage of the camera manufacture. These switches S3 and S4 handle 2-bit signals (A,
B) is configured, and the corresponding correction value γ (Ev)
is stored in the system controller 10, and when the 2-bit signal (A, B) is input to the system controller 10, the system controller 10 outputs a correction value γ corresponding to the signal, and the photometric sensor 17 measures the light. The brightness is corrected. That is, the photometric sensor 17a performs photometry at the same time as shooting, and the timing of shutter release is controlled based on the photometric data, so the shutter speed is controlled by correcting the photometric data, and the imaging sensitivity is corrected. It is something. for example,
(0,0)=O,OEv, (0,1)=+0.3Ev
, (1,0)=-0,3Ev, (1,1)=+0.
5Ev, and the imaging sensitivity of the solid-state image sensor 9 is 0.3Ev larger, the 2-bit signal (0, 1
) is input to the system controller 10, the controller 10 outputs a correction value γ of +〇, 3Ev corresponding to (0°1), and the photometric luminance of the photometric sensor 17 becomes +〇,
Since the 3Ev correction is applied, the shutter speed is +〇, 3E
v becomes faster, the exposure amount is lowered by 0.3 Ev, and variations in imaging sensitivity are corrected. Note that by increasing the number of switches and increasing the number of bits and storing correction values corresponding to each bit signal in memory, the amount of correction can be made finer.

S5 sets the selected date information with the first switch 55-1 for selecting date information of year, month, day, hour, and minute;
It is a date switch consisting of a second switch 55-2 to be corrected, S6 is a deck lid detection switch that detects whether the deck lid is open or closed, and 57-1 is a date switch that detects whether a floppy disk for recording video signals is loaded in the camera. A floppy detection switch 57-2 detects whether write protection is selected by the write protection selection tab of the floppy disk.

S8 is a switch that detects whether or not the accessory slide copier is connected, and S9 is a switch that detects whether or not the accessory negative copier is connected.

S10 is a switch for detecting the playback mode, and 311
is a field/frame switch that changes the recording format to field or frame.
312 is a zoom encoder switch group that monitors the focal length of the zoom lens.

S13 is a forced flash switch for forcing the flash to fire regardless of the brightness of the subject; 314
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, 22 is a control IC, which controls the drive of each actuator such as the DC/DC converter 12 and the clutch 13 based on the control signal from the system controller 10, and controls the shutter speed of the solid-state image sensor 9 and the flash circuit 18. A of photometric data based on light emission timing 17
/D conversion circuit, appropriate exposure detection circuit, etc.

To explain this control mIC22, the voltage control circuit 2
2a is DC/D by DC/DC control 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. In addition, photo interrupter circuit 2
2e counts a number of pulses corresponding to the amount of lens rotation output from the photocoupler 16 and outputs them to the system controller 10. Further, the amplifier circuits 22f1 and 22f2 convert the output currents of the spot photometric sensor 17a and the surrounding 1lJII optical sensors J and 7b into logarithmically compressed voltage signals 1-1, respectively, and output the signals. It is input to the double integral control circuit 22g via the switch swi. In addition, the control circuit 22g switches the switch SW1, and the amplifier circuits 22f1 and 22f2
The analog signal output from the system controller 10 is taken in, converted into a digital signal, and sequentially outputted to the system controller 10.

At 221, the solid-state image sensor 9 starts exposure in response to the signal ``Shutter Open'' 1, and the exposure amount becomes appropriate. - is a circuit for determining based on the detection signal from the photometric sensor 17a. The configuration of the circuit 22i for detecting proper exposure is such that the common terminal of the switch SWI is connected to the base of the transistor Q via the adder M1, the emitter of the transistor Q is grounded, and the collector is connected to the comparator CP.
is connected to the inverting input terminal of 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 Vec (not shown). Further, the power supply terminal Vce 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 SW is connected between the positive and negative electrodes of the capacitor C.
2 is connected, and the switch SW 2 is controlled to open and close by the output of "Shutter open" from the system controller 10.

In the proper exposure detection circuit 22i, when the switch SW2 is switched from "closed" to "open" by the above-mentioned "shutter open" signal, the capacitor C is charged by the current flowing through the collector of the transistor Q, and the capacitor C is The potential of the negative electrode of (
V) decreases and the normal input terminal voltage (Vo) of the comparator CP
When the exposure value drops below the level, 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 [close J].

Next, the D/A conversion circuit 2211 calculates the luminance correction amount output from the system controller 10, for example, the above-mentioned l5.
The adjustment amount for O1% variation adjustment is converted from a digital signal to an analog signal, and the correction signal is input to an adder M1 and added to the light reception signal of the photometry sensor 17.

The battery check circuit 22J checks the capacity of the battery. Further, the flash trigger circuit 22j outputs a "flash emission" trigger signal to the flash circuit 18 in response to a flash emission signal input from the system controller 1o. In addition, the flash control circuit #122m controls the charging of one capacitor for light emission of the flash circuit F418 (hereinafter referred to as charging of the flash circuit) by the control signal of the step-up start J, and controls the charging state of the flash circuit 18. It detects and outputs a charging completion signal to the system controller 10.

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

The time control circuit 24 is the same as the shutter control circuit 2.
The start and end of the fog light of the solid-state image sensor 9 is controlled by the shutter "open" and "close" control signals inputted from the shutter 2n. 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 field/frame recording signal input from the system controller 23. It also controls whether there are one or two recording tracks. Here, the details of the gain correction amount will be described later, but the "front light"
-1. OEv, 0
．． The correction amount is 5Ev, 10, 5Ev, →-1, OEv. Further, 26 is a recording magnetic head and disk;
A spindle motor 27 rotates the disk 26 . In addition, the system controller 23 also sends map information (information on empty tracks and recording finished tracks), information on recording in progress,
When the system controller 10 accepts a switch such as when the head is being fed, it sends information such as disapproval.

Next, in FIG. 2 showing the system configuration, the operation of opening and closing the shutter will be explained focusing on the shutter control circuit 22n that outputs the shutter "open" and "close" signals, the appropriate exposure detection circuit 221, and the system controller 10. do.

First, when the shutter "open" signal "'H" is output from the system controller 10, it is input to SW2, starts charging the capacitor C of the detection circuit 221, 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 E, .Furthermore, the system controller 10 operates the shutter only when flashing is necessary.
At the same time as the "Open" signal is output, a time count of the flash emission time is started, and when the time count of the flash emission time is finished, the system controller 10 to 7
A flash trigger signal is output to the flash trigger circuit 22j, and the flash starts emitting light.

Next, when the detection circuit 221 detects proper exposure, the comparator CP outputs the shutter "close J signal "H" to the system controller 10 and the OR circuit 32.
receives the above “H” output and sends “H” to the EXOR circuit 31.
The EXOR circuit 31 outputs "L" in response to the shutter "open" signal "HII" input to the input terminal at the other end, and notifies the system controller 23 and time controller 24 of the end of exposure. The timing at which the shutter “close” signal is output from the circuit 221 is a predetermined time 1.
If it is later than the camera shake limit time), the system controller 10 outputs a forced termination signal "H" to notify the end of exposure in the same way as the above operation.

The system controller 10 determines the output timing of the shutter "open" signal, the timing of the input of the shutter "close" signal, the timing of outputting the forced end signal (shake limit time), and modes such as "frontlight" and "backlight". It calculates up/down of the gain (details will be shown later) and outputs it to the video processing control circuit 25.

28 is a communication line between the system controller 10 and the system controller 23;
For example, switch information signals such as Sl, Sl, date, playback, field/frame, slide copier, negative copier, 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 metering mode for subject brightness is divided into ``Bright'', which allows you to shoot using only natural light, and ``Dark,'' which requires auxiliary light from a flash. For each case of "Dark", there is a case of "Front light" where the brightness of the main subject on the shooting screen and the brightness of the sub-subject in the background is properly balanced, and a case of "Front light" where the brightness of the main subject on the shooting screen is relative to the brightness of the sub-subject in the background. It can be divided into four types: dark "backlight". Incidentally, F Junko J also includes Dodochikari.

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 mentioned above and selects the appropriate shooting method, and an automatic mode that automatically determines whether or not the flash is necessary based on the metering results and selects the appropriate shooting method. There are three shooting modes: ``Forced flash mode'', which lets the flash fire and takes pictures, and ``Flash prohibition mode J'', which forcibly prohibits the flash from firing even when supplementary light from the flash is required. In the same table, "forced flash" and "flash prohibition" are equivalent to "forced flash mode" and "flash prohibition mode" respectively.
"Flash" or "AE (M light prohibited)" indicates the shooting mode selected by "Auto mode".

By the way, if the shooting method in the shooting mode described above is divided from the need for flash, the flash of the flash is performed with only natural light without flashing, and the fludge, the flash, the flash light of the natural light. It is divided into [flash mode], which uses both modes for shooting.In the classification of metering modes in Table 1 (see below),
"Flash off" and "rAE (Flash off)" become 1' natural light mode J, and [Forced flash J and [Fludge, S1] become [Fludge, 2. 'f need J.

Next, a photographing method in the photographing mode for the second photometry mode of this embodiment will be explained.

(1) Regarding “Natural Light Mode”; In this mode, if the bright backlight is set and the flash is turned off (-mode) to create a shadow, the brightness of the sub-subject will be relative to the brightness of the main subject. Since the main subject is shot at an appropriate exposure level, the sub-subject in the background is shot brightly.

When the main subject is properly exposed after 5Ev correction, the exposure is stopped and the image is photographed. Taking photos like this 4
- As a result, 11 subjects are photographed at 0.5 Ev lower than the appropriate exposure, but the background is prevented from being photographed extremely brightly, and the overall photograph is taken beautifully.Next, When shooting in "flash off mode" in the case of "dark backlight", the brightness of the sub-subject is relatively brighter than the brightness of the main subject, but the brightness of the sub-subject in the background is dark, so the main subject is not properly exposed. Even if the subject is photographed in such a way that the subject in the background will not be photographed excessively brightly. Therefore, the photometered brightness of the main subject is not corrected, and the main subject is photographed with proper exposure.

In addition, when shooting in "dark front light" and "bright front light" with [flash off mode, 1] and rAE (flash off), the balance between the brightness of the main subject and the brightness of the sub-subject is relatively different. This is a case where the brightness of the entire shooting screen has brightness and darkness within an appropriate range, so the brightness of the main subject and the brightness of the sub-subject are both taken into account, and the weighted average of each brightness is calculated. ' ) and take the picture so that its average brightness provides the appropriate exposure. Note that when the brightness of the entire photographic surface is extremely low according to the limit value of photometry, the weight of the brightness of the sub-subject is increased relative to the brightness of the main object in the above-mentioned average brightness. Also, the brightness on both sides of the photograph is at the limit of photometry! ? If the value is significantly lower than this value, I-Lies will be locked and photography will not be possible.

(2) Regarding [flash mode]: In the second mode, it is considered that the photographer's intention was to use the flash light source to take a picture regardless of the brightness of the main subject in forced flash mode J. Regardless of the photometry mode classification, the flash is emitted by the shutter 1-open control signal, and the main subject is photographed with appropriate exposure.

In addition, in the case of "bright backlight" (hereinafter referred to as "backlight flash mode J"), the luminance of the metered subject is -X
, Calculate the exposure time at which the sub-subject becomes appropriate by applying the correction of OEv. If the exposure time A P E,
After exposing to natural light until the above exposure time Tv, fire the flash 1. When the main subject becomes suitable, stop the exposure.

That is, the background is photographed using natural light with i E v brighter than appropriate, and then the main subject is properly photographed 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 J” and “dark forward light” (hereinafter referred to as [r
ft! i medium flash flash mode) applies +1, OEv correction to the metered brightness of the main subject, calculates the appropriate exposure time for the main subject, and applies the above correction @1, OEv.
When Tv is the APEX value of the exposure time added to Tv, after starting shooting, expose to natural light until the above exposure time Tv, then fire the flash and stop the exposure when the main subject becomes suitable. . 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 calculated by the system controller 10 separately for backlight flash mode J and dark flash mode J, 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 prior photometry information, "In backlight flash mode J, the secondary subject is
In the i-mode flash mode, the main subject can be directly metered at the same time as the solid-state image sensor 9 is exposed, and the flash emission timing can be determined. Directly meter the sub-subject brightness and set it to 1. The flash is emitted when OEv increases, and the exposure is ended when the main subject becomes suitable. In addition, 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. Fire the flash when OEv is low,
Exposure may be terminated 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 is composed of 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 often 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. This method measures the brightness and the brightness of the sub-subject 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 (
If the brightness of the main subject (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, then the photometric value Bv2 can be used as the brightness Bv^ of the sub-subject such as the background, but the photometric value The value Bv1 is the brightness B of the main subject
6. For example, if the main subject is small compared to the shooting screen and is backlit, the background light will wrap around the main subject and the photometric value Bvl will be If the shooting lens is a zoom lens, if the ratio of the size of the main subject to the shooting screen is arbitrarily changed by zooming, the photometric value Bv1 and the main subject brightness Bvs will change depending on the ratio. The errors will vary. Therefore, it is necessary to correct the photometric value Bvl to obtain the main subject brightness Bvs according to the ratio of the size of the main subject to the photographic screen and 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=Bvl −a −■. Note that the unit of subject brightness is expressed in Ev value.

Table 2 (described later) is an α map representing the correction amount α. In the same table, β is the photographing magnification that indicates the size of the subject relative to the photographic screen, and ΔBv is the difference between the peripheral brightness Bv2 and the central brightness Bvl, that is, ΔBv=Bv2−Bv1
It shows. 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. It has become.

Furthermore, as ΔBv increases, the brightness of surrounding objects becomes brighter than that of the main object, and the backlight becomes stronger, so the amount of light that wraps around from the surrounding objects to the photometric sensor 17a increases, so the value of the correction amount α becomes larger. There is. However, when β is smaller than 1/10G, the ratio of the size of the main subject to the shooting screen is so small that it cannot be considered as the main subject on the shooting screen, so the correction amount α is not included. .

Furthermore, 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 relatively accurately photometered 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 mode division into "frontlight" and "backlight" based on the main subject luminance L(vs) and the sub-subject luminance BvΔ will be explained.

Luminance difference (B
vA-Bvs) is ABv', when the sub-subject brightness is larger than a certain value (δ) compared to the main subject brightness, that is, when Δ13v'>δ, the sub-subject is higher than the main subject. Assuming too bright “backlight”, ΔBv″≦δ
In the case of , the brightness of the main subject and the sub-subject is balanced [default J].

Table 3 (described later) is a δ map giving the above constant value δ. The δ values in the same table are obtained from real photos, etc., 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.
Table constants are selected.

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

The exposure time is long, and the maximum brightness (
When the overall brightness of the shooting screen is lower than the camera shake limit brightness Bvfl (hereinafter referred to as the camera shake limit brightness), the flash is emitted to take a picture (set to flash mode J).

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 drying value Bvs' of the main subject brightness Bvs and the sub-subject brightness BVA that takes into account the respective brightnesses is calculated as the overall brightness of the shooting screen. This will be used as the average brightness. In the case of "11n light", Bvs' is given by Bvs' = Bvs / 4 + (3 - BvA ) / 4, and when Bvs' ≧ BvH, [Front light flash mode], Bvs' (When BvH, Since both sides of the image are dark, use the 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) is used.

In other words, when BvA-δ≧B v tl, the background is bright and the main subject is dark due to backlighting, so the flash is emitted [backlight flash mode], and BvA-δ
When <B v tl, Bvs≦BvA−δ<BvH
Even though it is backlit, the entire shooting screen is dark, so [
"Dark flash mode".

In addition, if the central brightness Bvt is low enough to reach the photometric limit of the photometric sensor 1.7a, the reliability of the photometric value is low. A weighted average (i
Bvs' is used to perform processing in the [low brightness processing mode]. That is, Bvs'=Bvs/30 (7-BvA)
Using Bvs' calculated as /8, process as [dark flash mode].

Below, [Natural light mode] and [Dark flash mode]
, [backlight flash mode], and [forced flash mode J], 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 T v H diagram, t and H(-2) are the limit exposure times that cause camera shake (shake limit shutter speed), which change depending on the output of the zoom encoder, that is, the value of the focal length f of the lens. be done.

tH (=2'' This is the delay time from when the solid-state image sensor 9 starts exposure in response to a start signal to when the flash starts emitting light, and in "flash mode", the flash is emitted after being exposed to natural light for a predetermined time tA. Furthermore, 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 J 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 proper exposure is reached within the time of the maximum shooting speed tH.

Exposure is carried out up to the maximum shutter speed time tH, and overexposure is carried out beyond the time ts at which proper exposure is obtained (tH-ts), so that the captured image is reduced in gain by the image processing control circuit 25. Overexposure is corrected.

By the way, since the exposure time of tH/2 corresponds to overexposure of IEv, ts≦to (however, to=tH/2> and t
The system controller 10 changes the gain correction amount and outputs it to the video processing control circuit 25 in cases where H>ts>t0. That is, if ts≦to, the excessive exposure time (tH-ts) will be shorter than tH/2, so a constant gain of 1. Decrease OEv, tH>t
If s>to, the excess exposure time (tH-ts) is tH
Since it becomes longer than /2, the constant gain of 0.5Ev is reduced.

0 When proper 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 video is recorded without exposure correction by the video processing control circuit 25.

■ Time ts when the brightness of the main subject is dark and reaches the appropriate exposure
exceeds the camera shake limit shutter speed tH.

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

(2) “Dark flash mode j 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 set to 1. O
Until the time when Ev reaches a low value (this time is defined as tA),
exposed by natural light, then a flash is fired,
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. In other words, ■When the proper exposure is reached while the flash is firing.

■When the proper exposure is reached within the camera shake limit time tH 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 light emission time tF ends).

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 case (2), when the camera shake limit time tH has elapsed, exposure is forcibly stopped to prevent camera shake, and the underexposure is transferred to 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 until the secondary subject in the background in the shooting screen has a value IEv higher than the appropriate exposure (this time is set as ta)
After that, the flash is emitted, and when the main subject is properly exposed, the exposure is stopped.

In this backlight flash mode, there are two types of shooting methods depending on the brightness of the subject. In other words, ■When the proper exposure is reached while the flash is firing.

■When the proper exposure is not reached even after the flash emission time t[ elapses after the flash is emitted.

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 (2), since the subject with a bright background is photographed in [backlight flash mode], if the main subject is exposed beyond the flash emission time tF until the time ts when the main subject is properly exposed, the natural light after the flash emission will be Since the secondary subject becomes excessively bright due to the exposure, the exposure is forcibly stopped after the flash emission time tF, and the exposure is not corrected by the image processing control circuit 25 for the photographed image.

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 above-mentioned flash emission delay time tA after the solid-state image sensor 9 starts exposure is set by 1. It is exposed to natural light until the time of .degree.OEv (this time is set as tA'=tA/2), then a flash is emitted, and after the flash is emitted, the exposure is stopped. [Backlight Flashino 2]
As in mode J, if the time ts at which the main subject is properly exposed exceeds the flash emission time t[, the exposure is forcibly stopped after the flash emission time tF, and the image processing control circuit 25 sets the gain to 1. , OEv is increased to correct the exposure. In other words, [backlight flash mode] where the distance of the main subject exceeds the limit that the flash light can reach.
In this case, since the flash does not work effectively as auxiliary light for the main subject, shorten the exposure time using natural light to half the exposure time using natural light in backlight flash mode 1 described above, and shoot so that the overall IEv is darker. Leave it behind.
After that, the flash is fired, and after the flash is finished, the exposure is forcibly stopped, and the overall gain is set to IEv on the captured image Vi floor.
It increases the number of people. In this way, the overall luminance difference between the main subject's brightness and the sub-subject's luminance is smaller than the actual luminance difference, so the overall lEv is lowered, and the entire image is corrected to a higher lEv at the first image stage. Therefore, the main subject can be photographed clearly, and the brightness balance between the main subject and the sub-subject can 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.

(4) “Forced flash mode J will be explained.

In the "forced flash mode", the flash is emitted when the maximum shutter speed tH has elapsed after starting exposure, and the exposure is stopped when the main subject is exposed to the proper JE exposure. In addition, if the time required for the main subject to be properly exposed exceeds the camera shake limit shutter speed tH, the exposure will be forcibly stopped when the camera shake limit shutter speed tH has elapsed to prevent camera shake, and the underexposure will be corrected by image processing. The control circuit 25 increases the video gain by 0.5 Ev for correction.

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

First, the main routine will be explained using the flowchart shown in FIG. In the first state when the battery is inserted into the camera, the system controller 10 is reset to the initial state (#5), and an initial setting subroutine is executed to initialize the system controller 10 (#5).
#10) Next, in #15 to #30, it is checked whether the camera is in the shooting state. In other words, check if the power supply battery is turned on (#15), and set the playback switch S10 to "playback mode".
At each step, check if is not selected (#20), if the deck's finger is not open (#25), and if the status of the deck lid has changed from "open" to "closed"(#30). do.

If the battery is not inserted in each of the above steps, a "battery removal" subroutine is executed (#200). If "Playback mode" is selected, "Execute the playback J subroutine (#210). If the deck is open, execute the "Prohibit recording/playback" subroutine to switch between recording and playback. This operation is also prohibited (#220). When a floppy disk for recording is inserted and the state of the deck lid changes from ``open'' to ``closed,'' execute the ``initial load'' subroutine, check the information on the floppy disk, and save that information. Load it into the system controller 10 (#500).

Next, check whether the main switch SO is turned on (#35>. If the main switch SO is turned off, shooting will not begin, so proceed to #110, set the shooting lens 1 to the initial position, and Turn off the display on the display circuit 21a (#115). If the voltage is being boosted to charge the flash circuit 18, proceed to #145, stop the boost, and turn off the flash charging L E in the viewfinder. Erase D display (red) (#150), HAL
It enters the T state (S160). In the HALT state, the sequence execution of the system controller 10 is paused, and the settings of the switches 21 are checked for changes at regular intervals (S170). If there are no changes in the settings, the HALT state is continued and the settings are changed. If so, return to #15.

If the main switch SO is turned on, the same switch S
Check whether O has changed from OFF to ON (S40
), when the main switch SO is turned on for the first time,
In order to charge the flash circuit 18, set the boost required J flag (S45).If it is not the first time it has turned ON, skip S45 and set the boost required J flag.
1a is displayed (S50), and the LCD display circuit 2
1a displays field/frame and single/self-timer mode selection, a counter for the number of shots, a battery warning, recording mode, etc.

Next, check whether the start switch S1 of AE and AP is turned on (S55). If the switch S1 is turned on, it indicates that the switch S1 is kept pressed.
Confirm the presence or absence of the "keep pressing" flag (S60). This means that when switch S1 is pressed again, AE and AF are performed again, and when switch S1 is held down, new AE and AF are performed.
E. This is because AF is not performed. If this flag is not set, execute the "Sl" subroutine and
Perform E (auto exposure) and AF (auto focus) (S80
0). Switch S1 is OFF or “
If the "Keep pressing" flag is set, next check whether there is a change in each mode of single/self-timer, field/frame, and date information switching (S65).
That is, single/self-timer mode changeover switch S15, field/frame mode changeover switch S1
1. When none of the date information mode switching switches 55-1 is held down, the switch 315.
311.55-1 and confirms whether there is a mode change.
If N, the [mode change] subroutine of S230 is executed. If the date changeover switch 55-2 is ON in S75, the "date change" subroutine of S240 is executed. If the field/frame mode changeover switch S11 is ON in S80, execute the [field/frame change] subroutine in S250, and if there is no change in each mode, check whether there is a date correction (S85). ), if any switch is held down, there is no mode change, so proceed to date correction (S85) without checking each mode changeover switch (S70 to S80 are skipped).Date correction switch 55-2 If has been pressed, the subroutine "r date correction" in S260 is executed. If there is no modification of the date information, next check whether flashing is necessary (S90~#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 or not flash is necessary. If the "forced light emission" switch S13 is pressed in S90, the "Flag for boosting required" is pressed in step S95), and the "flash prohibition" switch is pressed in S100.
If the switch 314 is pressed, a "boosting unnecessary" flag is set (S105).

Next, check whether the "boost required" flag is set, and if it is set, start boosting if charging is not completed.
LED display 19b in the viewfinder during flash charging (
(red) is turned on (#120 to #135), the boosting time is checked (S140), and when the boosting is completed within a predetermined time, the process returns to #15. Here, if the boosting is not completed within the predetermined time, a battery check is performed (S270), and if the "boosting required" flag is not set in S120, or if charging has already been completed in S125. If so, the process proceeds to steps #145 to #170 described above and enters the HALT state. Note that when each subroutine ends, the process returns to step S15(A).

Next, the "initial load" subroutine of S500 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, DC/DC is used to supply power to the spindle motor 27 and video processing control circuit 25.
The converter 12 is activated (#515).

Next, the spindle motor 27 and the video processing control circuit 25 are driven (#520) to read the contents written on the floppy disk 26, that is, 50 tracks of data, and create a map. In addition, the LCD display circuit 1
9b displays the track that is counting up, indicating that the contents of the floppy disk 26 are being confirmed (#525).

Next, check whether the "playback mode" is selected with the playback switch SIO (#530), and if the "playback mode" is selected, execute steps #535 to #545 to enter the "playback mode". In other words, i'! If there are no claws, recording is prohibited, so please set the flag ``Prohibit erasure J#540), and if there are claws, recording is allowed, so 1 erasure is allowed'' flag should be set (#540). 545), #210 “
Proceed to the "Playback mode" subroutine. If "Playback mode" is not selected in #530, check whether there is a recording prohibition claw on the floppy disk 26 (#550). If there is no claw, check the inserted floppy disk. 26 “
Recording prohibition J should be displayed on LCD display circuit 1.9 b#
555), stop the recording operation (#570), and
If there is a claw, check if there are any free tracks on the floppy disk 26 (#560), if there are no free tracks,
1. There are no empty trucks. ,, CD display circuit 19
b (#565), and stop the recording operation in the same way as when there are no claws (#570). If there is an empty rack, proceed to #600, and use the map information obtained in #525 to After moving the head to the recording track, the process returns to #15 of the main routine.

Next, “Sl” of #800 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 AF
Battery check, power supply, system controller 23
, make preparations such as white balance. That is, when boosting the voltage of the flash circuit 18, stop the boost (#805) and perform a battery check (#81).
0), set the white balance (WB) to a specific color temperature for daylight #8i5), and supply power to the solid-state image sensor 9, image processing control circuit 25° spindle motor 27, and other circuits. Start the DC/DC converter (#8201 system controller 23 (
The CPU 2) is reset (#825), and the color temperature sensor circuit 20 is activated (#830).

Next, execute the AF subroutine #1200 (described later), perform a focusing operation on the subject (#835), and if the reliability of the focus detection result is low due to low contrast and the focus is incomplete, , displays out-of-focus in the viewfinder,
Return to main routine #15 (#840"#850)
. When focusing is completed in #840, check whether the self-timer mode is selected (#855); if the self-timer mode is not selected, start the spindle motor 27 to drive the floppy disk 26. and prepares 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 obtained from the color information of the subject provided by the color temperature sensor circuit 20. Complete reading (#865), detect whether the light source is a fluorescent lamp or tungsten light (#87
0) If the light source is a fluorescent lamp or tungsten light, select [Flash Required] to fire the flash and take a picture.
Set the flag (#875).

This is because fluorescent lamps or tungsten light have a different color temperature distribution than sunlight, and it is better to take pictures with flash light that is similar to sunlight, so the flash is automatically activated. When 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 the metering of the subject brightness is completed in #880, #88
In steps 5 to #905, various flags are checked to confirm whether or not a flash is necessary. First, check the presence or absence of the "flash required" flag. If the $8851 flag is set, or if the flag is not set but "forced flash mode" is selected (#890), then Check whether "Flash Prohibition Mode" is selected (#895).

If "Flash Prohibition Mode" is not selected, it is the flash mode, so please check whether "Forced Flash Mode" in #890 is selected (#905), and if it is selected, set the "Forced Flash Mode" flag. Set it (#910
), check the charging state of the flash circuit 18 (#
915). The reason for setting the "forced flash mode J flag" 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 has not been started at step 60, the spindle motor 27 is started, preparations are made for recording onto the floppy disk 26 (#925), and the LED display 19a (green) indicates that the flash has been charged in the viewfinder. (#93
0), proceed to #970 and check the release switch S2. If charging of the flash circuit 18 is not completed in #915, start boosting the voltage for charging #935),
If the spindle motor 27 has been started in #860, its drive is stopped (#940), and the LED display 19a (red) indicating that the flash is being charged is displayed in the viewfinder (#945).
), The reason why the drive of the spindle motor 27 is stopped at #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 state of switch S1 (#950),
If it is OFF, return to #15 of the main routine and turn OFF.
If it is N, check switch S2 #955)
, if switch S2 is ON, main routine #
Return to step 15 and see the flash charging LED in the viewfinder.
Turn off the display 19a (red) (#965) and press # above.
Proceed to #920 to #930.

By the way, in #890, [If forced flash mode J is not selected, the flash will not fire, so leave it as is, #
Proceed to step 970 and check the release switch S2. Also, since the flash does not fire even when [flash prohibition mode] is selected in #895, #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, the switches so and s
i is checked (#1030 to #1035), and if either is OFF, the process returns to #15 of the main routine. If both switches SO and S1 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, check #22.
Executes subroutine 0 and prohibits all recording and playback operations.

If 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, the light emitting element 14 is blinked (#980), and the spindle motor 27 is activated.
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 the self-timer mode is not selected,
Skip #980 to #985 above and close up the main mirror 3, and then move the solid-state image sensor 9 and image processing control circuit 25.
(#995). Then, after counting the power up time (approximately 100m5) of the video processing control circuit 25 (#1000), the
Execute the release J subroutine and expose the solid-state R-surface element 9 (#1005). Next, after the exposure of the solid-state image sensor 9 is completed, record the photographed image on the floppy disk 26 (#1010), color Stop driving the temperature sensor circuit 20, video processing control circuit 25, and solid-state image sensor 9 (#
1015), lower the main mirror 3 (#1020)
, r head feed" subroutine (designates the next track based on the map information) (#1025), and returns to the main routine #15. 6. As explained above, in this embodiment, in the rsIJ subroutine sequence, In order to accurately measure the brightness of the main subject and the sub-subject, AF is executed first, and after the subject is accurately focused, the photometry (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 a light source, the color temperature setting is fixed to sunlight (flash light a,), so the flash should automatically fire to take pictures, and the flash-off switch can be turned off. When [Light Prohibition Mode] is selected in S14, the color temperature is automatically adjusted to the color temperature of fluorescent light or tungsten light (AWB
).

Next, r of #1200 (#835 above) to execute AF.
The subroutine of AFJ will be explained using FIG. 7.

First, turn on the power to the focus detection sensor 7 (COD line sensor) L (#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), and then waits until the interlaced signal INT1 that indicates the end time of charge accumulation in the focus detection sensor is input #1220), and the interlaced signal IN
When Tl is detected (#1225), the accumulated charges of the focus detection sensor 7 are transferred to the analog shift register, and the accumulated charges are output from the shift register one pixel at a time, A/D converted, and sequentially input to the system controller 10. (#
1.230).

Next, the default custom ID is detected from the data imported by the system controller 10 (#1235),
Determine the reliability of the defocus amount (■) #1240
), if it is unreliable due to low contrast, execute the "low contrast" processing subroutine +
i#1325), displays out-of-focus (#1330),
Return to main routine ($1320). If it is not unreliable due to low contrast l-, check whether the subject is accurately focused (#1245), and if it is, the information on the previous stop position of the photographing lens 1 and the current movement Find the current stop position information from the amount information,
Based on this information, the photographing distance is determined using a conversion coefficient corresponding to the focal pressure fif at that time, and the photographing magnification β is calculated from this photographing distance and the focal length f (#1305). Turn off the ED display 19a (green) (#131, 0 >, turn off the clutch circuit 13, switch the connection to the motor M from the photographing lens 1 to the main mirror 3 <#1.315), and proceed to the main routine. Return to step #1320. If the camera is not in focus in step #1245, it will focus in the following steps.

First, the lens extension amount conversion coefficient K is read from the ROM in the system controller 10 based on the current focal pressure 111f from the zoom encoder switch S12 (#12
50) Multiply the defocus scale f by the conversion coefficient K to determine the number of pulses N (=
KXD) (#1255), then enter the calculated number of pulses N into the "counter" in the system controller that monitors the rotation amount of the motor (#1260), turn on the clutch circuit 13, and connect to the motor. Switch from main mirror 3 to photographing lens 1 (#1265), and then switch to photographing lens 1.
starts driving (#1270).

Next, make it interruptible by the "counter"#
1275), wait until the counter value = 0 and a counter interrupt occurs #1280), and with the counter interrupt occurring (#1285), stop driving the photographing lens 1 and focus (#1290) ). Then, in order to confirm the in-focus state, charge accumulation in the focus detection sensor 7 is started again (#1295), and the interwoven signal lNTl
Wait until input (#1300), and then enter #1.
The process returns to step 225 to perform focus confirmation processing. If the focus is incomplete during the focus confirmation process, you will be charged $125 again from #1245.
0 and repeats the routine from #1250 to #1300 until focus is achieved.

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

First, the correction calculation of the ISO sensitivity is performed, that is, the corrected ISO sensitivity 5v (Svo+γ) is calculated from the standard 180 sensitivity Svo of the solid-state image sensor 9 and the imaging sensitivity variation correction amount γ (4t1503), and then the photometric sensors 17a, 17b The brightness Bvl (spot photometry value) at the center of the shooting screen and the brightness Bv2 (average photometry fB) around the shooting screen are determined by
) (#1505), then the double integration circuit 22g starts converting the luminance analog signal measured by the photometric sensors 17a and 17b into a digital signal (#1510), and then Check whether the A/D conversion of the brightness has been completed (#1515), and 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 the AP-AE lock is completed (#
1525), if AF-AE is not locked, #
Steps 1530 to #1545 are executed 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 if Bvl is over 11 #1
530), if it exceeds 11, the center brightness is too high, so fix Bv1 = 11 #1535), if it is less than 11, use the same Bvl and calculate the brightness difference ΔBv between the peripheral brightness Bv2 and the center brightness Bvl =Bv2-Bvl (#1540), then subtract the correction amount α shown in Table 1 from the center brightness Bv1 to obtain the main subject brightness Bvs (-Bv
l-α) (#1545). When AP-AE is locked, the brightness difference ΔBv and main subject brightness Bvs have already been calculated, so calculate #1530 to #15.
Skip step 45 and proceed to #1550 described below.
After switch S1 is closed in the main routine (#55), P-AE enters the photometry (AE) calculation subroutine for the first time (#8 of subroutine "Sl").
80), the process proceeds from #1525 to #1530 without being locked, and the subroutine "Sl
'' from #1040 to #865, and is locked for the first time when #880 returns to #1525.

Next, check if the peripheral brightness By2 is over 10.#
1550), if Bv2 exceeds lO, the peripheral brightness is too high, so Bv2 should be fixed at 10 #1555),
If it is 10 or less, use Bv2 as it is to set the sub-subject brightness BvA (#1560), then set the center brightness Bv1.
Check whether the brightness is low to the photometric limit value of the photometric sensor 17a (#1565), and if the brightness is low to the photometric limit value, the average brightness of the entire shooting screen for low brightness processing BvS'
Calculate using the following formula #1595), and proceed to #1600, that is, Bvs 7 ・ Bv^ Bvs"= 10 If the brightness is not low, calculate the reference value δ for backlight judgment from Table 2 and Bvs (# 1570), then subject brightness Bv
A and main subject brightness! Luminance difference Δ1]v' of 3 v s
(-BvA-Bvs) is compared with the determination reference value δ obtained in #1570 (#1575). Here, if ΔBv'>δ, it is determined that there is backlight and [the backlight 1 flag is set to
, (#1580), average brightness Bvs' for backlight processing
is set to Bvs (#15901 Proceed to #1600, and if ΔBv'≦δ, it is determined to be "frontlight", and the average brightness B V S ' for frontlight processing is calculated by the following formula ( $1585), proceed to #1600.

Bvs 3-BvA Bvs' = + Next, go to #1600 - # i Separate the shooting modes in 615. First, check whether the [Backlight] flag is set to Sera 1~ (#1600), and make sure the flag is set. If not (for "Front light mode"), #1585 or #
Compare the average 'n degree Bvs' of the entire shooting screen obtained with 1595 and the camera shake limit brightness BvH, and select the "flash mode".
and perform G1 for the mode of “natural light mode” (#1605
), if Bvs'≧BvH, then it is determined whether the flash necessity flag is set (#:1
606), here, if the flag is set, it indicates that the illumination light source is not sunlight but artificial light such as fluorescent light or tungsten light, and it was set in #875 in Figure 6. If the flag is not set, proceed to Routine 2 of "Dark Flash Mode".
Proceed to #1620 of “Natural Light Mode” Routine ■, B
If vs'< BvH, [Dark Flash Mode J
Proceed to #1675 of routine ■. If the "backlight" flag is set (in the case of "backlight"), the brightness (BvA -
δ) and camera shake limit brightness BvH #1610),
If (BvA-δ)≧BvH, set the [Bright Reverse] flag indicating backlight on a bright background (#1615)
, #1800 of [Backlight Flash Mode] Routine ■
Proceed to. If (3v^δ)<Bvl+, it is backlighting in a dark background, so proceed to #1675 of routine ① of [dark flash mode]. Next, we will explain the "natural light mode".

First, check whether the ``forced flash J'' flag is set (#1620). If the flag is not set, then check whether the ``bright and reverse'' flag is set (#1625), and then ``bright and reverse''. ” flag is not set, set the average brightness Bvs' to the control Bv value BvI ($1630), and set the correction amount ΔEvl (when directly metering the main subject brightness to O (#1635).
), in #1625, [If the bright and reverse J flag is set, the background is brightly backlit, so the control Bv value BvT is set to the value obtained by correcting the main subject brightness Bvs by +0.5, that is, B
Set vT-Bvs+0.5 (#1640), and set the above correction amount ΔEvil to (0,5-α) (#164)
5) Note that α is the correction amount shown in Table 1, and its value varies depending on the imaging magnification β.

Next C, control Bv value BvT and lowest brightness that can be photographed By
Compare #1650), and if BvT≦Bvl, the shooting screen is too dark, so set the flag "No shooting"(#1660), display the "No shooting" flag in the viewfinder (#1665), and Execute the “Release Lock” subroutine to prohibit shooting (#1670), BvT
> If there is BvL, 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 routine ① of the [dark flash mode] will be explained.

First, check whether 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 taken using natural light. If the flag is not set,
Brightness with main subject brightness Bvs corrected by +1.0 (Bvs+
l) and camera shake limit brightness BvH #1680),
The setting of the control By value is changed depending on the brightness of the main subject. In other words, if Bvsl≧BvH, control B
Set the brightness (Bvs+1) which is the main subject brightness Bvs +1°0 corrected to the v value BvT (#1685), Bvs
If +1<BvH, the main subject brightness is lower than the camera shake limit brightness, so the control Bv value BvT is set to the camera shake limit brightness B.
Fix to yH (#1690).

Next, the correction amount ΔEvi of the exposure amount due to flash emission
Assuming that the coefficient K added to l is O, #1695), the value of the photographing magnification β is classified into three types (#1700), and the correction amount ΔE of the exposure amount due to flash emission is calculated for each of them.
C#1705 to #1715) for setting vFL, that is, if β>(1/25), set the correction amount ΔEvF to 0.#1705), (1/25>≧β>(1
155), the correction amount ΔEvF is (0,5-K
), and if (1155)≧β, set the exposure amount correction amount ΔBvFL due to flash emission to (
1,0-K) (#1715). This is to correct 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 of the flash 1v.
Flash light emission amount Iv (=Iv+Δ
EvfL), and then calculate the aperture value A using the following formula from the above Iv', film sensitivity Sv, and subject distance information Dv.
Calculate vD (#1720), that is, AvD = Iv' +5v-Dv = Iv+5v-Dv+ΔEvF Next, compare the aperture fiiAvD obtained in #1720 with the aperture 1liAvoz corresponding to the focal length at that time. ,
Determine whether the distance to the subject exceeds the limit that the flash light can reach (#1725), if AvD > Avoz, a "remote" warning indicating that the distance to the subject exceeds the limit that the flash light can reach. (#1730),
Furthermore, set the [Remote] flag (#1735)
, set the aperture value input V port to Avoz (#1740),
If AvD is 5Avoz, do nothing and set the aperture value AvD to Avoz (#1740).

Next, the brightness BvH (=TvH+-AvD-8v) calculated from the aperture value Avd obtained from #1740, the maximum shutter speed TvH, and the film sensitivity Sv and #168
5 or with the control By value BvT set in #1690 #1745), and if BvT≦BvH, proceed directly to #1765 and perform the above control B v @ B v
The flash light emission timing time Tv is calculated using T. BvT) BvH, check whether the "clear/reverse" flag is set (#1750); if the flag is not set, proceed to #1765; if the flag is set, set the control Bv value BvT ( TvH+AvD-
3v) (#1755), and set the main subject brightness Bvs.
The control Bvl[BvT (=T
Compare vH+AvD-3v) #1760), Bv
If s≦βvT, the process proceeds to #1765, and the flash light emission timing time Tv is calculated using the control Bv@BvT set in #1755. Also, Bvs>B
For vT, #162 of “Natural Light Mode” Routine ■
In addition, in #1765, the flash light emission timing time Tv is calculated from the following formula.

Ev=BvT +5v Tv=Ev-AvD =BvT +5v-AvD Next, compare the flash timing time Tv calculated in $1765 with the maximum shutter speed TvH or camera shake limit shutter speed TvH #1770. #1
780), if Tv≧TvH, it is the time when flash emission cannot be controlled, so set the timing time Tv to the maximum shutter speed TvH (#1775), and if Tv≦TvH, before emitting the flash. To avoid camera shake, set the timing time Tv to the camera shake limit shutter speed TvH (#1785).
), set the "flush required" flag to cell l-L (#
1790 ), return to main route (#
1795), if Tvll < Tv < TvH (#1770, #1780), the T obtained in #1765
Using v, proceed to #1790 to #1795.

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

First, check whether the "Flash Prohibition" flag is set (#1800). If the flag is set, proceed to #1625 of the "Natural Light Mode" routine ■. If not, the control By value BvT is corrected from the sub-subject brightness BvA i1. The value minus OEv, that is, BvT = BvA - 1°0 should be set #1805), the brightness difference between the control Bv value BVT and the main subject brightness BvS, that is, the brightness difference from the appropriate natural light component. Calculate ΔEvN (=Bvs-BvT) #1810), the above luminance difference ΔEvN and ~1°OE
Compare v (#1815), if ΔBvN>-1, 0, fix ΔEvN to -1, 0 and control B v value Bv
T is the main subject brightness Bvs plus correction amount 1, OEv,
That is, set BvT = Bvs + 1.0, ΔEv
If N≦-1, 0, set with #1805 and #1810/BvT = Bvs + l, 0 and ΔEvN = Bvs-
Use BvT.

Then, the correction amount ΔEvF of the exposure amount due to flash emission
Set the coefficient K added to L to the value of α #1825)
, the process proceeds to #1700 above, and the processing from #1700 described in "Dark flash mode" is performed.

By the way, in backlight flash mode J, the predetermined timing time Tv for flash emission is calculated from the brightness of the sub-subject (however, when δ≦By≦2, the timing time for flash emission is calculated from the main subject brightness), and the exposure is After the start, the flash is emitted after a predetermined time Tv 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 the embodiment, since the exposure is stopped when the main subject is properly photographed after the flash is emitted, the main subject is properly photographed, but the sub-subject is overexposed by the flash emission time.

Therefore, a second embodiment, which is not limited to the above-mentioned embodiment, will be described below, which can accurately adjust the balance of brightness between the main subject and the sub-subject. That is, a certain correction time X [seconds] is calculated from the brightness difference between the main subject and the sub-subject, and
The flash is emitted X [seconds] before v elapses.

The value obtained by multiplying the above predetermined time Tv by m in [seconds] is X'',
If the timing time of flash emission is x'C seconds], which is the fixed time X corrected from the same X''', then X''-2Tv
c seconds] x' = x''-x [seconds] T v , x' = 2 - x (seconds) X' is the timing time for flash emission.

Regarding the second embodiment using the predetermined flash emission time X' in the above-mentioned "backlight flash mode", FIG. 8(b)
This will be explained using a flowchart.

Note that the flowchart in Figure 8(b) is similar to that in Figure 8(a).
This is inserted between #1765 and #1770.

First, in #1765, the flash emission timing time Tv is set.
After being calculated, check whether the [clear/reverse] flag is set (#1895), and if it is not set, proceed directly to #1770. If the flag is set, the correction amount ΔEvF from the appropriate amount of flash light is calculated from the brightness difference ΔEvN from the appropriate amount of natural light using the following equation (#1900).

ΔE v N > ΔEvF=log2 (1-2 Next, the required amount of flash light Iv from the main subject distance
s is calculated from the following formula (#1905).

l vs=Avoz+Dv-8v Next, compare the flash light emission amount Ivs obtained in #1905 with the actual light emission amount Iv.#1910) Ivs≦I
If v, 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).

ΔF, vF' = Ivs-1v+ΔEvF Also, Iv
If s>Iv, the light emission amount 1vs' (corrected by adding the brightness difference correction amount ΔEvF to the flash light emission amount Ivs
=Ivs+ΔEvF) (#1920), and the above correction amount ΔEvF' is calculated from the difference between this light emission amount 1 vs' and the actual light emission amount 1v (#1925), that is, ΔEvF' = Ivs'-1v Next, check whether the above correction amount ΔEvF' is less than or equal to OEv (#1930), and if ΔEvF'>0, ΔEv
If ΔEvF'≦0, proceed to #1940 using ΔBvF' as is and determine the correction time corresponding to the correction amount ΔEvF' from the table shown in Table 3. do.

Next, a flash emission timing time x'C seconds] is calculated from the X obtained in #1940 and the predetermined time Tv using the following formula (#1945).

x'== 2 T v-x Next, convert the timing time X [seconds] of fludge and L emission into Tv (Ev) using the following formula, and proceed to #1770 (#
1950).

T v =1 o g 2 (1/ x') This concludes the explanation of the second embodiment, and then #2000 (the sixth
The "release" subroutine (#1005) in the figure will be explained using FIG. 9.

The "release" subroutine is comprised of routines for "natural light mode,""flashmode," and "forced flash 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 stop when the main subject becomes appropriate, so the sensor for photometry is set to spot metering at the center of the shooting screen. The modes are divided into ``natural light mode,'' ``flash mode,'' and ``forced flash mode.'' If the "forced flash" flag is set in #2010, the process proceeds to the "forced flash mode" routine in #2235 to #2275 (described later), and if the "flash required" flag is set in #2015, the routine advances to #2
The process advances to the "flash mode" routine from 090 to #2230 (described later), and if the "flash required" flag is not set, the process advances to the "natural light mode" routine 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 imaging sensitivity variation correction value γ (#2025), then timer T1 and timer T2 are set to TvH maximum. Shutter speed tH (=2 > 2 division value to and camera shake limit shutter speed th (=2-Tv
H, and start the countdown, and at the same time start the exposure of the solid-state image sensor 9 (#203
0), then time t.

It is confirmed whether the exposure amount of the solid-state image sensor 9 reaches an appropriate level by the time the period of time has elapsed. In other words, check the timer T1-〇.
2035>, TI>O, the voltage value of the capacitor C of the circuit 221 that detects that the amount of charge accumulation in the solid-state image sensor 9 has become appropriate (hereinafter referred to as the exposure voltage value) and the reference voltage value Vo. Compare #2040), if Vo<V, the amount of charge accumulation has not reached the appropriate value, so #203
Return to step 5 and check the timer T1 again. If ■0≧■, the amount of charge accumulation has reached the appropriate value, but the charge accumulation will continue until time t14, so the gain of the captured image will be adjusted. Set the -1,0 correction flag (#2045
), proceed to #2280 to #2290, close the shutter,
The positive gain value -1°0 is output to the video processing control circuit 25, and the process returns to the main routine.

If T1=0 in #2035, timer T1 is set to
to start the countdown, and then set the time to
Check whether the exposure amount of the solid-state 11 element 9 reaches the appropriate level by the time t has elapsed (#2250 to #2060).
If the solid-state image sensor 9 reaches proper exposure by the time o elapses, charge accumulation will be excessive until time 11H, so a flag is set to correct the gain of the captured image by -0.5.

(#2045), proceeds to #2280-#2290, closes the shutter, and outputs the gain correction value -0.5 to the video processing control circuit 25. and return to the main routine. The solid-state image sensor 9 is suitable by the time t O elapses, i
If the T exposure is not reached (TI=0 at 82055), then check whether the solid-state imaging probe 9 reaches the appropriate Tf'' exposure during the time LH-t, o (#2070, #2075>, that is, If V o ≧ V (#2070), the solid-state image sensor 9 has reached the appropriate exposure, and the shutter is closed (
#2280), since there is no gain correction, output the gain correction value O to the video processing control circuit 25 (#2285), and return to the main loop f'i (#2290>, Vo<■
If so, check whether T2=O (time t11 has elapsed) (#2075). If T2=0, the exposure time of the solid-state imaging probe 9 exceeds the camera shake limit time, so the solid-state imaging is forced. Stop the charge accumulation on the probe 9 (#2080), and adjust the gain of the photographed image to 5 to correct the underexposure.
Set the correction flag to cell l-L (#2085), close the shutter (#2280), output the gain correction value +0.5 to the video processing control circuit 25 (#2285), and return to the main routine (#2290). ).

Next, to explain the flash mode (#2090>, similarly to the natural light mode, first, the D/A conversion circuit 22h (#2095).

Next, check if the backlight 1 flag is set #2100), and if the flag is set, check #215
5-Proceed to #2230 "Backlight J flash mode shooting (described later), and if it is not set, select #2105~#
2150's normal flash mode photography. In normal flash mode photography, timer T1 and timer T2 are each set to v, flash emission timing time tA (=2).
Then, the camera shake limit shutter speed tH is set to the camera l-1, the timer TI, and the timer T2 start counting down, and at the same time, the exposure of the solid-state image sensor 9 is also started (#2105). Next, exposure is performed using natural light until T1=0 (time tA elapses), and when T1-0 is reached, the flash is emitted (#2110~・#2115), and at the same time, timer T3 is activated to emit the flash. The current time t and F are set and the countdown is started (#2120). During flash emission (T3>0), if the reference voltage value Vo and the exposure voltage 1V are set to Hikyo 117, and Vo≧V (#2125~
#2130m solid-state m image element 9 has reached proper exposure,
Proceed to #2280-#2290, close the shutter, and set the gain correction value to 0 since there is no gain correction.
125 and returns to the main routine.

Next, if Vo<V does not result in proper exposure during flash emission, the solid-state image sensor 9 will be properly exposed by the time 11 elapses after the camera shake limit time (after time t has elapsed) after flash emission (T2=O). Check if it reaches (#2135 ~ $2
140). When the proper exposure is reached, (#2140), #2
As in step 130, the process proceeds to #2280 to $2290, the shutter is closed, and since there is no gain correction, a gain correction value of 0 is output to the video processing control circuit 25, and the process returns to the main routine. If the proper exposure is not reached by the time the camera shake limit time tH elapses (T2-〇), the charge accumulation in the solid-state image sensor 9 must be forcibly stopped when the time t]1 has elapsed.#
2145), set a flag to correct the gain of the captured image by 10.5 to correct the underexposure (#21).
501 Proceeds to #2280 to #2290, closes the shutter, outputs the gain correction value +0.5 to the video processing control circuit 25, and returns to the main routine.

Next, #21. When the ``backlight'' flag is set to OO and you are shooting in the ``backlight'' flash mode,
Also make sure the "remote" flag is set.#
:2155), if the flag is not set, set the flash emission timing ta in timer T; #2160), if the flag is set,
The timing time t^' for flash emission is set in timer T (
=t^/2) (#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, when the flash emission timing time t^ has elapsed (#2165
), fires the flash (#2170), simultaneously sets the timer T to the flash firing time tf, and starts the countdown (#2175), and while the flash is firing (T>0), the solid-state image sensor 9 is properly set. When it comes to exposure (#2180, #2190), #2280 to #2290
Then, the shutter is closed, and since there is no gain correction value, a gain correction value of 0 is output to the video processing control circuit 25, and the process returns to the main routine. If proper exposure is not achieved during flash emission, after flash emission (after time tF)
, to forcibly stop charge accumulation in the solid-state image sensor 9 #21
85), close the shutter without setting the gain correction flag for the photographed video (#2280), output a gain correction value of 0 to the video processing control circuit 25 since there is no gain correction (#2285), and Return to the routine (#2290), #2160 to #2185 [When shooting in backlight flash mode J, the background is brightly backlit, so even if you forcibly stop the exposure in #2185, the gain correction of the shot image will not be performed. .

Even when the "remote" flag is set, the flash is emitted after the elapse of the flash emission timing tA'' in the same way as when the above-mentioned "remote" flag is not set. When the exposure is appropriate, the shutter is closed, and since there is no gain correction, a gain correction value of 0 is output to the video processing control circuit 25, and the process returns to the main routine (2200 to #2220. #2
280 to #2290), if proper exposure is not obtained during flash emission, the charge accumulation in the solid-state image sensor 9 is forcibly stopped after flash emission #2145), and the gain of the photographed image is corrected by +1.0. Set the flag (
#2230), closes the shutter (#2280), and outputs the gain correction value +1.0 to the video processing control circuit 25 (#2280).
2285), return to the main routine (#229
0).

In #2195 to #2230, when shooting in "remote" [backlight flash mode], the exposure time using natural light is half of the time t^ when shooting in "backlight flash mode", so the exposure is forced in #2225. When stopped, the gain correction of the captured video is +1°0.

Next, to explain the forced flash mode (#2235), first, the main subject brightness correction value ΔEv[[ and the 130 sensitivity Sv corrected by the imaging sensitivity variation correction value γ are output to the D/A conversion circuit 22h. (#2240), then set the maximum shutter speed tH and camera shake limit shutter speed tH in timer T1 and timer T2, respectively, and at the same time start the countdown of timers TI and T2, also start the exposure of solid-state image sensor 9. (#2245)
0 Next, when the maximum shutter speed tH has elapsed (T
1=O), use the flash #2250 to #225
5) Check whether the solid-state image sensor 9 reaches the appropriate fog light before the camera shake limit time tH elapses (T2=O) (#2
260 to #2265) 0 If proper fog light is reached before camera shake limit time tH elapses, close the shutter (#228
0), since there is no gain correction, output the gain correction value 0 to the video processing control circuit 25 (#2285) and return to the main routine (#2290).If the proper exposure is not reached, the camera shake limit time th has elapsed. When this occurs (when T2 = 0), the charge accumulation of the solid-state image sensor 9 should be forcibly stopped #2270>, and a flag should be set to correct the gain of the captured image by +0.5 in order to correct the underexposure. #
2275), closes the shutter (#2280), outputs the gain correction value 10.5 to the video processing control circuit 25 (#2
285), return to 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.

However, 11 and 17 may also be used so that the flash light emission is also stopped when exposure is stopped at t' of the joint.

(below, margin) No. table note) [Main]: Main subject brightness.

Bvs’ : Average brightness value of the shooting screen No. table No. table note) tf: Flash duration

[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 for controlling the camera section of the electronic camera, FIG. 5 is a flowchart for executing the initial load applied to the main program, and FIG. 6 is a flowchart for executing the initial load applied to the main program. FIG. 7 is a flowchart for executing AF applied to the flowchart of S1 above, and FIG. 8(a) is a photometric AE calculation applied to the above flowchart. 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 for executing the release applied to the flowchart of S1 above. This is a flowchart for 1... Photographing lens, 7... Focus detection sensor, 9...
...Solid carrier element (imaging means), 10...System controller, 11...Control circuit block for AF, 15...IC52 that drives the photographing lens drive motor
2...Control IC123...System controller (
electronic shutter function control circuit), 25... video processing control circuit, 26... disk, 27... spindle motor. Applicant Minolta Camera Co., Ltd. Agent
Patent Attorney Yasushi Itatani Kazuo 1 Diagram

Claims (1)

[Claims] (1) An imaging means, a video processing circuit for recording the signal from the imaging means on a recording medium as a video signal, a drive mechanism for driving the recording medium, and an autofocus mechanism for driving the photographing lens into focus. The electronic still camera is characterized in that either or both of the power to the recording medium drive mechanism and the video processing circuit are turned on after the autofocus mechanism completes the focusing operation. Electronic still camera.