JPH0324529A - Exposure control device - Google Patents

Abstract

PURPOSE:To make a shutter speed at the time of slow synchro photographing appropriate by setting a shutter speed for control at a prescribed shutter speed when a calculated shutter speed is lower than the prescribed shutter speed. CONSTITUTION:When flash photographing is decided by a flash photographing deciding means 2, the shutter speed TV is calculated based on the output of a photometric means 1 by a shutter speed arithmetic means 3. When the shutter speed TV is lower than the prescribed shutter speed TVf2 which is lower than a flash synchronizing maximum speed TVx, the shutter speed for control TVc is set at the prescribed shutter speed TVf2 by a shutter speed limiting means 4. Therefore, even at the time of the flash photographing, the shutter speed for control TVc never becomes lower than the prescribed shutter speed TVf2. Thus, the shutter speed at the time of the slow synchro photographing is made appropriate.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an exposure control device, and is particularly suitable for a camera having a flash photography function that synchronizes with the completion of one shutter curtain run.

[Prior Art] Conventionally, for example, when photographing a person against a night view background,
It has been proposed to perform slow synchronized photography, which combines flash photography for photographing people and slow shutter for photographing the background. On the other hand, Japanese Patent Application Laid-Open No. 63-53529 proposes, when using a slow shutter, to detect the amount of image blur of a subject and to issue a warning when the amount is greater than a predetermined value. [Problem to be solved by the invention] In slow synchro photography, if the shutter speed is set too long, the subject may move, resulting in double shots. In particular, when the flash fires in synchronization with the completion of the first curtain of the shutter, the subject may move immediately after confirming that the flash has been fired, and the exposed area may become redundant. There is a problem with overlapping images. The present invention has been made in view of these points, and an object of the present invention is to provide an exposure control device that can appropriately control the shutter speed during slow synchro photography. [Means for Solving the Problems] In order to solve the above problems, in the exposure control device according to the present invention, as shown in FIG.
a photometering means 1 for measuring, a flash photography determination means 2 for determining whether or not flash photography is used, a shutter speed calculation means 3 for calculating the shutter speed TV for flash photography based on the output of the photometry means 1; When the shutter speed TV set is equal to or less than a predetermined shutter speed TVf2, which is smaller than the flash synchronization maximum speed TVx,
shutter speed limiting means 4 for setting the control shutter speed T V c to the predetermined shutter speed TVf2;
It is characterized by having the following. It should be noted that the camera shake detection means 5 detects the amount of camera shake, the camera shake correction means 6 drives a part of the photographic lens based on the detection output of the camera shake detection means 5 to correct camera shake, and the camera shake correction means 6 determines whether or not camera shake correction is effective. further comprising a determining means 7 for determining, the determining means 7
When it is determined that the correction is not effective, the shutter speed calculation means 3 sets the shutter speed TV to the maximum flash synchronization speed TVx, and when it is determined that the correction is effective, the shutter speed is adjusted based on the output of the photometry means 1. It is preferable to configure the system to calculate the speed TV. However, FIG. 1 is an explanatory diagram showing the configuration of the present invention functionally divided into blocks, and in the embodiments described later, means 1 to 7 will be described.
All or part of this is realized by microcomputer software. [Function] The function of the present invention will be explained below with reference to FIG. A photometer 1 measures the brightness BV of the subject. The exposure control device of the present invention has a flash photography function, and a flash photography determining means 2 determines whether or not flash photography is being performed. When flash photography is determined, the shutter speed TV is calculated by the shutter speed calculating means 3 based on the output of the 1,000-stage photometer. When this shutter speed TV is equal to or less than a predetermined shutter speed TVf2 which is smaller than the maximum flash synchronization speed TVx, the shutter speed limiting means 4 sets the control shutter speed TVc to the predetermined shutter speed TVI2. Therefore, even during flash photography, the control shutter speed T Ve does not become slower than the predetermined shutter speed TVf2. This predetermined shutter speed T
By setting Vf2 to the camera shake limit shutter speed, double copying can be prevented during slow synchro photography. Note that if the camera shake detection means 5 detects the amount of camera shake, and the image stabilization means 6 drives a part of the photographic lens based on the detection output of the camera shake detection means 5 to correct the camera shake, the camera shake detection can be performed. and the predetermined shutter speed TVf2 compared to the case where camera shake correction is not performed.
can be slowed down. However, if sufficient camera shake correction cannot be performed due to the amount of camera shake being too large, there is a risk that image shake will occur in the resulting photograph. Whether or not the correction is effective is determined by the 1,000-stage judgment 7, and when it is determined that the correction is not effective, the shutter speed TV may be set to the flash synchronization maximum speed TVκ by the shutter speed calculation means 3. [Embodiment] A single-lens reflex camera equipped with a zoom lens with an image stabilization function will be described below as an embodiment of the present invention.
Figure 2 is a block circuit diagram of the camera. In the figure, μC1
is an in-body microcomputer (hereinafter referred to as "in-body microcomputer") that controls the entire camera and performs various calculations.

AFcT is a light receiving circuit for focus detection, which includes a CCD line sensor for detecting the focus of an object within the distance measurement range (described later), a drive circuit for this CCD line sensor, and an A/D circuit that processes the output of the CCD line sensor. It is equipped with a circuit for converting the data and transmitting the data to the in-body microcomputer μC1, and is connected to the in-body microcomputer μC1 via a data path. This focus detection light receiving circuit AFc. Information on the amount of defocus of the subject within the distance measurement range can be obtained. LM is a photometric circuit that A/D converts photometric values within a photometric range, which will be described later, and transmits them to the microcomputer μC1 in the body as luminance information. DX is a film sensitivity reading circuit that reads film sensitivity data provided on the film container and serially outputs it to the microcomputer μC1 inside the body. The D I SPC inputs display data and display control signals from the microcomputer μC1 inside the body, and displays the display section DISP+ (fourth
This is a display control circuit that causes the display section DISPI (see FIG. 47) in the viewfinder to perform a predetermined display. BL is a camera shake detection device built into the camera body, and includes a microcomputer μC2 and a CCD area sensor X for camera shake detection. The detailed configuration of this camera shake detection device BL will be described later. FLC is a flash circuit,
In this example, it is built into the camera body. The detailed configuration of this flash circuit FLC will also be described later.

X is a synchronizing contact (so-called X contact), which turns ON when the shutter completes one curtain run, and turns OFF when the shank machine oval (not shown) completes charging.

LE is an in-lens circuit built into the interchangeable lens, which transmits information specific to the interchangeable lens to the microcomputer μC1 in the body, and also performs control for image stabilization. The detailed configuration of this in-lens circuit LE will be described later. M1 is an AF motor that drives a focus adjustment lens within the interchangeable lens via an AF coupler (not shown). Also,
The MDI is a motor drive circuit that drives the AF motor M1 based on focus detection information, and its forward rotation, reverse rotation, and stop are controlled by commands from the microcomputer μCl in the body. ENC is an encoder for monitoring the rotation of the AF motor M1, and the in-body microcomputer μ
Outputs a pulse to the counter input terminal CNT of C1. The in-body microcomputer μC1 counts these pulses, detects the amount of extension from the infinity position to the current lens position, and detects the shooting distance of the subject from this amount of extension (number of extension pulses). T V CT is a shutter control circuit that controls the shutter based on a control signal from the in-body microcomputer μC1. The detailed configuration of this shutter control circuit TVoT will be described later. AVc is an aperture control circuit that controls the aperture based on the control signal from the microcomputer μC1 inside the body. M2 is a motor for winding and rewinding the film and charging the shutter mechanism. Further, MD2 is a motor drive circuit that drives the motor M2 based on commands from the microcomputer μC1 in the body. WB is a white balance circuit that detects the three primary color components of light, calculates ratio signals of R (red light) and G (green light) with respect to B (blue light), and converts these into digital signals. The information is transmitted to the internal microcomputer μC1. The detailed structure of this white balance circuit WB will be described later. Next, we will explain the power supply-related structure. E is a battery that serves as a power source for the camera body, and 6T r 1 is a first power supply transistor that supplies power to a part of the circuit described above. T r 2 is a second power supply transistor that supplies power for driving the motor inside the lens, and has a MOS configuration. VDD is the microcomputer μC1 inside the body and the circuit LE inside the lens.
This is the operating power supply voltage for the camera shake detection device BL, film sensitivity reading circuit DX, and display control circuit DISPC.
is the operating power supply voltage of the focus detection circuit AFcT and the photometry circuit LM, which is supplied from the power supply battery E via the power supply transistor Tr1 under the control of the power supply control signal PWI. Vcc
2 is the operating power supply voltage of the lens motor, and is supplied from the power supply battery E via the power supply transistor T r 2 under the control of the power supply control signal PW2. ■cc0 is the motor drive circuit M D1. Shutter control circuit TVc. Aperture control circuit AVc. , is the operating power supply voltage of the motor drive circuit MD2, and is directly supplied from the power supply battery E. Note that when circuits with large current consumption, such as motor drive circuits MDI and MD2, operate, the current supplied from the power supply battery E increases.
The battery voltage may drop temporarily. Therefore, a backup capacitor CB is charged from the power supply battery E via a diode DB for preventing backflow, and this capacitor C
The power supply voltage VDD is supplied from B to the microcomputer μC1, etc. Next, we will explain the switches. SL is set to O by pressing down on the first step of the release button (not shown).
This is the shooting preparation switch that is turned on. When this switch S1 is turned on, the interrupt terminal IN of the microcomputer μC1 in the body
An interrupt signal is input to the TI, and preparatory operations necessary for photographing, such as autofocus (hereinafter referred to as rAF), photometry, and display of various data, are performed. S2 is a release switch that is turned on by pressing down the second step of the release hook. When this switch S2 is turned on, a photographing operation is performed. S3 is a mirror up switch that is turned ON when the mirror is raised, charges the shutter mechanism, and turned OFF when the mirror is lowered. S Ml. SM2 is a selection switch for selecting an exposure mode, and is used to set any of modes I, n, and III, which will be described later. SE is a battery attachment detection switch that turns OFF when battery E is attached to the camera. When the battery E is installed and the battery installation detection switch SE is turned OFF, the capacitor C1 is charged via the resistor R1, and the microcontroller μ in the body is charged.
The reset terminal REI of C1 changes from ゜'Low' level.
This causes an interrupt to the in-body microcomputer μC1, the built-in oscillator automatically operates, and the in-body microcomputer μC1 executes the reset routine shown in Figure 4.Next. , the configuration for serial data communication will be explained.The photometry circuit LM, the film sensitivity reading circuit DX, the display control circuit DSIPC, and the camera shake detection device BL have a serial manual SIN, a serial output SOUT, and a serial clock SC.
Data communication is performed serially with the microcomputer μCl in the body via each signal line of K. The object of communication with the microcomputer μC1 in the body is the chip select I/terminal CSLM.
．． Selected by CSDX, CSDISP, and CSBL. That is, when the terminal CSLM is at the "Low" level, the photometric circuit LM is selected and the terminal CSDX is at the "Low" level.
When the level is W, the film sensitivity reading circuit DX is selected, and when the terminal CSDI SP is at the "Low" level, the display control circuit DI SPC is selected and the terminal C
When SBL is at “L01 level,” camera shake detection device B
L is selected. Furthermore, the three signal lines S IN, SOUT, and SCK for serial communication are connected to the lens internal circuit LE.
When selecting the lens internal circuit LE as a communication target, the terminal CSLE is set to "Low" level. Next, the detailed circuit configuration of the intra-lens circuit LE built into the interchangeable lens is shown in FIG. 3 and will be explained.
The figure shows the image stabilization lens N, which has an image stabilization function.
This shows the circuit configuration of BL. In the figure, μC3 is an in-lens microcomputer that performs data communication with the camera body and control for image stabilization. M3 and M4 are pulse motors for driving the image stabilization lens, and drive the image stabilization lens in the k direction and the l direction, respectively, which will be described later. MD3 and MD4 are motor drive circuits that drive pulse motors M3 and M4 in the positive direction or negative direction, respectively, in response to control signals from the microcomputer μC3 in the lens. ZM is a zoom encoder for detecting the focal length of the zoom lens, and DV is a distance encoder for detecting the amount of extension from the infinite position at each focal length.
These are used to calculate the imaging magnification. Also,
Focal length data is also used to calculate the camera shake limit shutter speed. VCC2 is motor drive 0 path MD3, MD
4 and the power supply path to the two pulse motors M3 and M4, VD
D is a power supply path to circuits other than those mentioned above, GND2 is a ground line connected to motor drive circuits MD3, MD4 and two pulse motors M3M4, and GND1 is a ground line connected to circuits other than those mentioned above.

The terminal CSLE is an input terminal for an interrupt signal, and when the interrupt signal is input from the camera side to the lens side, the microcomputer μC3 in the lens executes the interrupt LCS INT. SCK is a clock input terminal for serial data transfer, SIN is a serial data input terminal, and SOUT is a serial data output terminal. REIC is a reset circuit that resets the microcomputer μC3 in the lens when the voltage Vol supplied from the camera body becomes below the normal operating voltage of the microcomputer μC3 in the lens.R3 and C3 are the microcomputer μC3 in the lens. This is a reset resistor and capacitor for resetting.

RE3 is the reset terminal for the microcomputer μC3 inside the lens, and it connects the lens from the body to the internal rotation f? Voltage VOO for driving 8 L E is supplied, and terminal RE3 changes from “Low” level to “High” level by resistor R3 and capacitor C3.
When the level changes, the microcomputer μC3 in the lens performs a reset operation. SLE is a lens attachment detection switch, which is turned OFF when an interchangeable lens is attached to the camera body BD and mounted. That is, when the interchangeable lens is removed from the camera body, the switch SLE is turned on and both ends of the capacitor C3 are shorted. As a result, the charge stored in the capacitor C3 is discharged, and the reset terminal RE3 of the microcomputer μc3 in the lens becomes "'Los".
It becomes level. After that, when the interchangeable lens is attached to the camera body, switch SL2 is turned OFF, capacitor c3 is charged by power supply voltage VOO via resistor R3, and after a predetermined time determined by the time constant of resistor R3 and capacitor C3 has elapsed, The terminal RE3 changes to ゜'High'' level, and as mentioned earlier, the microcomputer μC3 in the lens performs a reset operation. SBL is the image stabilization prohibition switch, and when this switch SBL is turned on, image stabilization is not performed. The camera side also performs the normal AE program operation.Now that the hardware of the camera body BD and the lens internal circuit LE in this embodiment has been explained, the software will be explained next.

In addition, the camera shake detection device BL, flash circuit FLC, shutter control circuit TVcT, white balance circuit WB
The detailed configuration of the software will be explained as necessary in the software description below. First, the software of the in-body microcomputer μC1 will be explained. When the battery E is attached to the camera body BD, the microcomputer μCl in the body executes the reset routine shown in FIG. In this reset routine, the internal microcomputer μC
1 resets various ports and registers (including flags) and enters a halt state (halt state R) (#5).
When this stopped state is reached, the oscillator built into the microcomputer μC1 in the body automatically stops. Next, when the first stroke of the release button is pressed down, the shooting preparation switch S1 is turned on, and a signal that changes from the "High" level to the "L ou+" level is sent to the interrupt terminal INTI of the microcomputer μC1 in the body. is input, and as a result, the in-body microcomputer μC1 executes the interrupt INTI shown in FIG. First, the microcomputer μ in the body
C1 sets the power supply control terminal PW1 to a high level, turns on the power supply transistor Tri, and supplies power to each circuit (#10).

After that, the interrupt terminal SIINT of the microcomputer μC2 of the camera shake detection device BL changes from ゛'High'' level to ゛'Lou+.
Output a signal that changes to the level (#12>.Next,
The lens communication A subroutine is executed to read predetermined lens data (#15). Lens communication includes lens communication A, which transmits data from the lens to the body, and lens communication B, which transmits data from the body to the lens. Figure 6 shows the subroutine for lens communication A. When this subroutine is called, first, the terminal CSLE is set to ``L os'' to notify the microcomputer μC3 in the lens that data communication will be performed (#150).
Then, 2 bytes of data is exchanged with the lens! '
#155). The first byte is body status TCPB
is transmitted from the body to the lens, and from the lens, meaningless data FF. (The subscript "H" means ■ hexadecimal number) is transmitted to the body.The body status ICPB includes data indicating the type of body and the type of lens communication.In the second byte, the lens status ICPL is transmitted to the body. is transmitted to the body, and meaningless data FFH is transmitted from the body to the lens. Lens status ICP
L includes data indicating the type of lens (whether it is an image stabilization lens or not) and ON/OFF of the image stabilization prohibition switch Set. The in-body microcomputer μC1 determines whether the replacement lens is an image stabilization lens NBL based on the data input from the lens, and if it is an image stabilization lens, it sends 6 bytes of data, and if it is not an image stabilization lens, it sends 5 bytes of data. Input each data (#160 to #
170). Then, to indicate the end of data communication, the terminal CSLE is set to the "'Higb" level, and the process returns (#175). The third byte of data input from the lens to the body is the focal length Mf, and the fourth byte is the open aperture value AV.
o, 5th byte is maximum aperture value AVi*ax, 6th byte.
The key is the conversion coefficient K. which converts the defocus amount DF into the rotation speed of the AF motor M1. , the 7th byte is distance data.
If the lens is not an image stabilization lens, a total of 7 bytes of data up to this point will be input. If the lens is for image stabilization, data on the amount of image stabilization that can be achieved is also input from the lens. This will be discussed later. #1 in Figure 5
When the lens communication A subroutine is completed in step 5, the in-body microcomputer μC1 determines whether the interchangeable lens is an image stabilization lens NBL based on the input lens data (#20). If it is an image stabilization lens, the power supply control terminal PW2 is set to "High" level, the power supply transistor T r 2 is turned on, and the lens internal circuit L is turned on.
When the lens is not used for image stabilization, the power supply voltage Vcc2 is supplied to the lens E, and when the lens is not used for image stabilization, the power supply control terminal PW2 is set to the "Low" level, the power supply transistor Tr2 is turned off, and the supply of the power supply voltage ■cc2 to the lens internal circuit LE is stopped. (#2
5, #30). Next, the AF subroutine is executed to perform the AF operation (#35). This AF subroutine is shown in Figure 8. When this subroutine is called, first, it is determined whether or not the flag AFEF indicating focus is set (#200>. If the flag AFEF is set, it is assumed that the focus state is already established and the AF operation is performed. Returns without performing.If the flag AFEF is not set, the focus detection light receiving circuit AF
c. Integration (charge accumulation) of CCD line sensor in
After completing the integration, the A/D converted data is dumped, a correlation calculation is performed based on the input data, and defocus and tDF are calculated (#205 to #220). Based on this defocus amount DF, it is determined whether or not the focus is on, and if the focus is on, the flag AFEF is set and the process returns (#225, #230). On the other hand, if the lens is not in focus, the flag AFEF is reset, a lens drive subroutine is executed, and the process returns (#235, #240).

FIG. 9 shows this lens driving subroutine.

When the same subroutine is called, My in the body. The controller μC1 calculates the rotation speed N of the AF motor M1 by multiplying the obtained defocus amount DF by the lens drive amount conversion coefficient KL, determines whether the rotation speed N is positive or not, and if it is positive, the AF motor A control signal is output to the lens drive circuit MDI to rotate the AF motor M1 in the forward direction, and if it is negative, a control signal is output to the lens drive circuit MDL to rotate the AF motor M1 in the reverse direction, and the respective returns (#245 to # 260). Next, the counter interrupt flow for driving the lens by the rotational speed N is shown in FIG. 10 and will be explained. Counter interrupt is A
Encoder E for monitoring the rotation of F motor M1
Executed every time a pulse is input from the NC. In this interrupt, the in-body microcomputer μCl first subtracts 1 from the absolute value IN of the rotational speed N to create a new value IN+, and determines whether or not this IN+ has become 0 (#280, #285).
When INl=O, a stop signal for the AF motor M1 is output to the motor drive circuit MDI for 10 msec, and then the AF
Output a control signal to turn off motor M1 and return (#290, #295). If Nl = 0, return immediately. After completing the AF subroutine in #35 of FIG. 5, the microcomputer μC1 in the body executes the color temperature detection subroutine (#40), and controls the white balance circuit WB for detecting this color temperature. Third
It is shown in Figure 8. Three light receiving elements PDR, PDC
．． The light receiving surface of PD8 has R (red light), G (green light), and B.
Color filter PR that transmits (blue light)
, FC, F8 are arranged to obtain signals SR, Sc, and SB indicating the light intensity of the three primary colors R, G, and B, and each signal is logarithmically compressed by a logarithmic compression circuit. In the figure, an operational amplifier connected to a diode as a feedback impedance is a logarithmic compression circuit. Then, the differential amplifier at the subsequent stage calculates the difference between the signals S R and S H, S. , S days, the respective ratio signals SR/Ss, Sc/S
B is obtained, A/D converted at a predetermined period, and transmitted to the microcomputer μC1 in the body. Each signal S R, S C
, SB are treated as logarithms, so a ratio signal can be obtained by taking the difference using a differential amplifier. Figure 11 shows the subroutine for color temperature detection (AWB: auto white balance). When this subroutine is called, the in-body microcomputer μC1 inputs the signal A/D converted by the white balance circuit WB shown in FIG. 38, and determines whether the light source is a fluorescent lamp (
#300. #305). If the light source is a fluorescent lamp,
The power of G (green light) increases, and the ratio signal S c/S
e becomes noticeably larger. By detecting this,
Determine whether the light source is a fluorescent lamp. Then, if the light source is a fluorescent lamp, the flag FLLF is set, and if the light source is not a fluorescent lamp, the flag FLLF is reset, and the process returns (#310 to #320). #40 in Figure 5
After completing the color temperature detection subroutine, the in-body microcomputer μC1 executes the AE calculation (automatic exposure calculation) subroutine (#45). This AE calculation subroutine is shown in Fig. 12. When called, the microcomputer μC1 in the body first sets the film sensitivity S.
V is read from the film sensitivity reading circuit DX through serial communication, and then the open photometry value BVo is read from the photometry circuit LM through serial communication (#350, #355).
Then, the photometric value BV is calculated as B V = B Vo + A V
o, and the exposure value EV is determined as EV=BV+SV (
#360. #365). Next, the microcomputer μC1 in the body
calculates the camera shake limit shutter speed when no image stabilization lens is attached from the focal length f (mm) data as 1/f (see), and calculates this as the avex value T.
V f 1. Similarly, when the image stabilization lens is attached, the camera shake limit shutter speed is determined as 3 2 / f Csec), and this is converted to the abex value TVf2 (#368). Are you wearing an image stabilization lens here? 32 at normal time.
I believe that with double the exposure time and avex value, it is possible to reduce the camera shake limit shutter speed to -5EV. Then, the exposure mode is determined according to the state of the selection switches SM■ and SM■ for mode selection, and depending on the determination result, mode I (normal mode) or mode ■ (portrait photography mode) is selected.
, mode ■ (landscape photography mode), and return (#370 to #390). The above mode I. II. Before explaining the I subroutine, AE program diagrams for each mode are shown and explained in FIGS. 34 to 36.

Figure 34 is an AE program diagram for mode I (normal mode). In this mode, for the exposure value EV, from low brightness to camera shake limit shutter speed TVf1 or TVf2, the combination is the open aperture value A V o and the shutter speed TV that is less than TVf1 or TVf2. If the exposure value EV becomes larger than that, the shutter speed TV and aperture value AV are distributed in the ratio of 1:1 to the exposure value E■. Then, when the aperture value AV reaches the maximum aperture value AVmax, the distribution is finished and only the shutter speed TV is changed. For flash photography, the shutter speed is T.
This is done when Vf1 or TVf2 is less, or when the brightness BV is less than 5. Figure 35 is an AE program diagram for mode ■ (portrait shooting mode). In this mode, the shooting aperture value AV is set to the aperture value AV/3 obtained from the shooting magnification β, and the obtained aperture value A
The shutter speed TV is determined from V and the exposure value EV, and when the shutter speed exceeds TVmax, the aperture value AV is changed. And the shutter speed TV is T
When the brightness is less than VII or TVf2 or the brightness BV is less than 5, flash photography is performed. For camera shake correction lenses, the slower limit of shutter speed for flash photography is set to TV=2 (1/4 second in real time) or TVf2, whichever is larger.This is the camera shake limit shutter speed TV.
Setting f2 as the lower limit is natural because it is necessary to prevent camera shake, but setting TV=2 as the lower limit is because the subject is rarely stationary when photographing people, and double shots may occur. This is because it often creates shadows, which is not good. This is a particular problem in flash photography, since the subject may decide that the photograph is complete and move after the flash fires. A graph for determining the aperture value AV73 from the photographic magnification β is shown in Fig. 37. In FIG. 37, the horizontal axis shows the imaging magnification β, and the vertical axis shows the aperture value AVβ.
The scale on the vertical axis shows the aperture value in abex value, and the F number is also written in parentheses. When β≧1/10, set AV=6 (F8), and when 1/10>β≧l/40, set the value on the straight line connecting AV=6<F8) and AV=4 (F5.6). and when 1/40>β≧1/80, AV
=4<or open aperture value), and 1/80>β≧1/
160, AV=4 (F4) and AV=8 (F1
6), and when 1/160>β, A
V=8 (F 1 6). β〉1/20 is used for macro photography by stopping down a little to gain depth of field.
When 20≧β≧1/100, the depth of field becomes shallow for portraits (people), and when β<1/100, the depth of field is gradually stopped until β≦1/160″cAV-8 when shooting landscapes. The depth of field is obtained.In this embodiment, a data table is provided in which the photographing magnification β in this graph is used as an address and the aperture value AVβ is read out as data.Third
Figure 6 is an AE program diagram for mode III (landscape photography mode). In this mode, in order to obtain depth of field, the predetermined aperture value F1 is set from the camera shake limit shutter speed TVfl or TVf2 to the maximum shutter speed TV+*ax.
1 (AV=7). Then, the shutter speed determined from the exposure value EV is the maximum shutter speed TVma
If the speed is faster than x, the aperture is changed from the predetermined aperture value (AV=7) to the maximum aperture value AVmay while keeping TVmax. Camera shake limit shutter speed T due to exposure value EV
When the shutter speed is lower than Vfl or TVf2, the shutter speed TV is set to TVfl or TVf2, and the aperture value AV is changed from the predetermined aperture value FIL (AV=7) to the open aperture value AV.
Open until o. After opening the aperture to the maximum aperture value A Vo, the shutter speed TV is further slowed down. At this time, no flash photography will be used. Next, the subroutines of the modes I, n, and I[[ will be shown and explained in FIGS. 13 to 15. First, the subroutine of mode (2) shown in FIG. 13 will be explained. When this subroutine is called, the microcomputer μC1 in the body determines whether the interchangeable lens is an image stabilization lens, and if it is an image stabilization lens, the aperture value AV and shutter speed T are determined.
Execute the subroutine AV and TV calculation ■ to determine V (#400, #405). The subroutine for this AV/TV operation (■) is shown in Figure 15. When the same subroutine is called, first the aperture value AV is
Find it by AV=-EV/2-TVf2+AVo (#6
55). When this aperture value AV exceeds the maximum aperture value AVw+ax, the aperture value AV is the maximum aperture value AV! lIa
×, and if it is less than the minimum (open) aperture value A Vo, set the minimum aperture value AVo as the aperture value AV (#
620 ~ #635). Then, from the obtained aperture value AV and exposure value Ev, the shutter speed TV is set to TV - EV - AV.
Find it using (#640). If this shutter speed TV is less than or equal to the maximum (fast) shutter speed TVmax, the process returns directly (#645). Also, the shutter speed T
When V exceeds the maximum shutter speed 7Vmax,
Maximum shutter speed TV as shutter speed TV w
Set ax and recalculate the aperture value AV using AV=EV-TV (#650, #655). When this aperture value AV exceeds the maximum aperture value AVmay, the maximum aperture value AVsax is set as the aperture value AV, and the aperture value AV exceeds the maximum aperture value A.
If it is less than Vmay, return as is (#66
0, #665). After completing the AV/TV calculation subroutine in #405 of FIG. 13, the microcomputer μC1 in the body determines whether the light source is a fluorescent lamp (FLLF=1) (#415). When the light source is a fluorescent lamp,
Execute the flash photography FL1 subroutine and return (#420). When the light source is a fluorescent lamp, the overall color becomes greenish due to its color temperature, and in order to prevent this a little and retain that feeling, we set the ratio of the amount of natural light to the amount of flash light to 1:2. (Normally, the ratio is 1:1). The subroutine of this flash photography FLI is shown in Fig. 16. When the subroutine is called, first, the control exposure value EV is set to EV = EV + 1.5, Set the natural light precept to 1.5 EV under (#670)
．． And the shutter speed I decided on was the same as the flash!
III! Determine whether it exceeds k high-speed TVx (#6
75). Here, the flash synchronization maximum speed TV x is the abex value TVx = 8 (1/250 seconds in real time). When the shutter speed TV exceeds the flash synchronization maximum speed TVx in #675, the shutter speed is set in #680. Set the flash synchronization maximum speed TVx as the TV, and do nothing when the flash synchronization maximum speed TVx is below.
Proceed to #685 for each. In #685, it is determined whether the shutter speed TV is less than the camera shake limit shutter speed TVf2. When shutter speed TV is less than camera shake limit shutter speed TVf2 in #685, #690
Set the camera shake limit shutter speed TVr2 as the control shutter speed T V e, and when the camera shake limit shutter speed TVf2 or higher, set the shutter speed TV obtained as the control shutter speed T V e in #695, and set the shutter speed TV obtained in #700, respectively. Proceed to. In #700, the aperture value AV is determined by AV = EV - TV e. When the obtained aperture value AV is the minimum aperture value AVo, the minimum aperture value AVo is set as the control aperture value AVc.
The aperture value AV obtained is the maximum aperture value AVllax.
When the value exceeds the maximum aperture value AVmax, set the maximum aperture value AVmax as the control aperture value AVc, and when neither of the above values apply,
The obtained aperture value AV is set as the control aperture value AVc (#710 to #730). Then, in order to make the flash light emission amount (light control amount) under 0.5Ev, the SV
=SV+0.5, set flag FLF to indicate flash photography, and return (#7
35, #740〉. Returning to the flow of FIG. 13, when it is determined in #415 that the light source is not a fluorescent lamp (FLLF=0), the process moves to #455, and it is determined whether the calculated shutter speed TV is less than the camera shake limit shutter speed TVf2. judge. #455
Shutter speed TV is camera shake limit shutter speed TV
When the value is less than f2, the process advances to #480 and executes a subroutine for flash photography PL2 (#480). This subroutine for flash photography FL2 is shown in FIG. In this subroutine, the ratio of the amount of natural light to the amount of flash light is set to 1:1, and control is performed so that the main subject is properly exposed and the background is under IEV. First, in #750, 1 is added to the exposure value EV obtained by calculation to make the control exposure value EV under IEV, #75
In step 1, it is determined whether the interchangeable lens is an image stabilization lens NBL. If the interchangeable lens is an image stabilization lens, execute the AV/TV calculation subroutine described above; if it is not an image stabilization lens, perform the AV/TV calculation described below.
Execute the calculation subroutine ■ to calculate the aperture value AV and shutter speed TV, and proceed to #755 for each (#7
52, #753). In #755, the shutter speed TV calculated by the calculation is the same as the flash i1N! Maximum speed TV
If the shutter speed TV exceeds the flash synchronization maximum speed TV x in #755, it is determined whether the shutter speed TV exceeds the flash synchronization maximum speed TV x in #760, and the flash synchronization maximum speed TV x is set as the control shutter speed TV e. #77
If the shutter speed TV is equal to or lower than the maximum flash synchronization speed T V x in #755, the process advances to #762 and it is determined whether the interchangeable lens is an image stabilization lens NBL. If the interchangeable lens is a camera shake correction lens, it is determined whether the shutter speed TV obtained by calculation is less than the camera shake limit shutter speed TVf2 (
#764). If the shutter speed TV is less than the camera shake limit shutter speed TVf2 in #764, the camera shake limit shutter speed TVf2 is set as the control shutter speed T V c in #766, and the process proceeds to #770. #764
Shutter speed TV is camera shake limit shutter speed TV
If it is f2 or more, control shutter speed TV with #768
Set the shutter speed TV obtained by calculation as c, and proceed to #800. When it is determined in #762 that the interchangeable lens is not a camera shake correction lens, it is determined in #767 whether the shutter speed TV is less than the camera shake limit shutter speed TVII. If shutter speed TV is less than camera shake limit shutter speed TVf1 in #767, #7
Set the camera shake limit shutter speed TVfl as the control shutter speed TVc in 6, and proceed to #770.
If the shutter speed TV is equal to or higher than the camera shake limit shutter speed TVfl in #767, the shutter speed TV calculated by the calculation is set as the control shutter speed TV c in #768.
Set the exposure value E and proceed to #800.In #770, set the exposure value E.
The aperture value AV is calculated by subtracting the control shutter speed T V c from V. Then, when this aperture value AV is less than the maximum aperture value AVo, the maximum aperture value AVo is used, when the aperture value AV exceeds the maximum aperture value AVmax, the maximum aperture value AVmax is used, and when none of the above, the calculated aperture value is used. AV is set as the control aperture value A V c, and the process proceeds to #800 (#775 to #795).
In #800, the film sensitivity Sv is set to sv=sv+i, the flash light amount is set to IEV below the appropriate value,
At #8o5, set the flag FLF indicating flash photography and return. Returning to the flow shown in FIG. 13, when the shutter speed TV is equal to or higher than the camera shake limit shutter speed TVf2 in #455, it is determined in #460 whether the brightness BV is less than 5. If the brightness B■ is less than 5 in #460, #48
At 0, the subroutine for flash photography PL2 described above is executed, control is performed to provide contrast using the flash light, and the process returns. On the other hand, if the brightness BV is 5 or more in #460, the calculated shutter speed TV is set as the control shutter speed TVc, and the control aperture value AVc
Set the aperture value AV calculated as , and return (#465.#470). In #400, if the interchangeable lens is not an image stabilization lens, the AV/TV calculation subroutine (see Figure 15) is executed (#425).
．． In this subroutine, the aperture value AV is set to AV in #660.
= EV / 2 − T V r 1 + A V o
Find this and proceed to #620. The following has already been explained, so it will be omitted. After determining the aperture value AV and shutter speed TV in #425, it is determined in #430 whether the brightness BV is less than 5. If the brightness BV is less than 5 in #430, #4
At 80, execute the subroutine for flash photography FL2 and return. If the brightness BV is 5 or more at #430, determine whether the shutter speed TV is less than the camera shake limit shutter speed TVf1 at #435. 435
Shutter speed TV is camera shake limit shutter speed TV
If it is less than fl, execute the flash photography FL2 subroutine in #480 and return. In #435, the shutter speed TV becomes the camera shake limit shutter speed TVr1.
If it is above, set the calculated shutter speed TV and aperture value AV as the control shutter speed TVc and control aperture value AVc, respectively, and return (#465)
, #470). In this case, natural light photography is used. Next, FIG. 14 shows the subroutine of mode ■ (portrait photography mode). When this subroutine is called, first, the photographing magnification β (the size of the main subject occupying the photographic screen) is calculated from the distance data and focal length data input from the lens (#500). Then, based on the graph shown in FIG. 37, the aperture value AVβ is determined from the data table using the imaging magnification β as an address, and this is set as the calculated aperture value AV (#505, #510). Next, it is determined whether this calculated aperture value AV is less than the open aperture value AVo (#51
5). If the calculated aperture value AV is less than the open aperture value AVo, set the open aperture value AVo as the calculated aperture value AV in #520, and if the calculated aperture value AV is greater than or equal to the open aperture value AV o, in #520
Skip each step and proceed to #525. In the portrait photography mode, in order to perform flash photography, it is determined in #525 whether the camera shake limit shutter speed TVf] exceeds the maximum flash synchronization speed TVx, and if it does,
In #530, the maximum flash synchronization speed TVx is set as the camera shake limit shutter speed TVfl, and if it does not exceed it, skip #530 and proceed to #535. In #535, the background should be IEV under,
Let the exposure value EV be EV=EV+1. And #54
In 0, the shutter speed TV is determined by TV=EV-AV. In #545, it is determined whether the determined shutter speed TV exceeds the maximum flash synchronization speed TV x. If it exceeds, the control shutter is activated in #55o. Speed T V e
Set the flash synchronization maximum speed T V x as #5
At step 55, execute the flash photography FL3 subroutine and return. This subroutine for flash photography FL3 is the flow from #770 onward in FIG. 17, and here, the aperture value AV is re-determined, assuming that the above-mentioned aperture value AV=AVβ does not provide an appropriate exposure value. #54
In step 5, if the calculated shutter speed TV is less than or equal to the maximum flash synchronization speed T V x, the process proceeds to #56o, where it is determined whether the interchangeable lens is the image stabilization lens NBL.
If the interchangeable lens is an image stabilization lens for #560,
In #565, it is determined whether the calculated shutter speed TV is less than the camera shake limit shutter speed TVf2. In #565, the calculated shutter speed TV is the camera shake limit shutter speed TV.
If f2 is not grooved, control shutter speed T with #570
The camera shake limit shutter speed TVf2 is set as Ve, and the flash photography FL3 subroutine is executed in #555. If the calculated shutter speed TV is equal to or higher than the camera shake limit shutter speed TVf2 in #565, the calculated shutter speed TV is set as the control shutter speed T V c, and the calculated aperture value AV is set as the control aperture value AVe (#585.# 590). Also, set the film sensitivity SV to SV=SV+1 and set the flash light amount to IEV under (#595). Furthermore, the flag FLF is set to indicate flash photography, and the process returns (#600). If the interchangeable lens is not a camera shake correction lens in #560, it is determined in #575 whether the calculated shutter speed TV is less than the camera shake limit shutter speed TVf1. #575 calculates shutter speed TV
is less than the camera shake limit shutter speed TVfl, #
In step 58o, the camera shake limit shutter speed TVfl is set as the control shutter speed T V c, and in step #555, the flash photography FL3 subroutine is executed. On the other hand, #5
If the calculated shutter speed TV is equal to or higher than the camera shake limit shutter speed TVfl in step 75, the process executes steps #585 to #600 and returns. Next, the subroutine of mode ■ (landscape photography mode) will be explained based on FIG. 15. When the same subroutine is called, first, in #602, the aperture value AV is set to AV=7,
In #604, the shutter speed TV is calculated as TV=EV-AV. Then, in #605 it is determined whether or not the interchangeable lens is an image stabilization lens NBL.If the interchangeable lens is an image stabilization lens NBL in #605, then in #606 the TV
Determine whether ≧TVf2 or not, and if not TV≧TVf2, set #6 1 0te aperture value AV to AV=EV-TVf2+
Calculate with AVo. If the interchangeable lens is not an image stabilization lens in #605, it is determined in #608 whether TV≧TVfl, and if TV≧TVfl is not, the aperture value AV is calculated as AV=EV−TVfl+AVo in #615; Proceed to #620 for each. The processing after #620 (control for natural light photography) is as described above, so the explanation will be omitted. Note that if TV≧TVr2 in #606 or TV≧TVfl in #608, the process advances to #645. Returning to the flowchart of FIG. 5, when the AE calculation subroutine is finished in step #45, the in-body microcomputer μC1 executes the data communication subroutine I in step #50 in order to output data to the camera shake detection device BL. This data communication I
Figure 18 shows the subroutine. When this subroutine is called, the in-body microcomputer μC1 first inhibits the interrupt DEINT from the camera shake detection device BL, and
BL is set to "Low" level, serial communication is performed four times (4 bytes), and 4 bytes of data is output to the camera shake detection device BL (#9 0 0 to #910>.These 4
Byte data includes focal length f, control shutter speed T
Vc, type of lens, and presence/absence of focusing. After outputting these data, the terminal CSBL is set to “High”.
” level and interrupt DEI from the camera shake detector ifBL.
Allow NT and return (#915, #920). The microcomputer μC2 of the camera shake detection device BL receives the signal that the terminal CSBL of the microcomputer μC1 in the body changes from the “High” level to the “Low” level, and issues an interrupt CSBL.
Execute L. To explain this as shown in FIG. 22, the microcomputer μC2 inputs 4 bytes of data through data communication I, and flags D indicating that data communication I has been executed.
Set TP and return (#1105, #11
10). Here, the detailed configuration of the camera shake detection device BL will be explained. FIG. 41 shows the range of camera shake detection (image shake detection) that occupies the photographic screen S. In the figure, Sa is the distance measurement range by the focus detection light receiving circuit AFcT, sb is the range of camera shake detection (image shake detection) by the camera shake detection device BL,
Sc is the photometry range by the photometry circuit LM. FIG. 42 is a block circuit diagram of the camera shake detection device BL. μC2 performs calculations for camera shake detection and its sequence control (especially data communication with the microcomputer μC in the body and C
This is a microcomputer that performs integral control of the OD area sensor X. X is a two-dimensional CCD area sensor, 35
It has 24 pixels in the vertical direction and 36 pixels in the horizontal direction, which is the same ratio as the lI-Finorem size. Each pixel has a light receiving section, a storage section, and a transfer section, and the accumulated charge in the storage section changes depending on the photocurrent obtained at the light receiving section. The accumulated 8F charge obtained in the storage section of each pixel is serially read out by the transfer section and inputted to the data input section DT of the microcomputer μC2. The data input section DT of the microcomputer μC3 is provided with an A/D conversion section, which converts the analog signal output from the CCD area sensor X into a digital signal and stores it in the built-in memory. MPD is a monitor light receiving element, SWa, SW
b is a switch element, Ca is a capacitor, and CMP is a converter, which are provided to control the integration time of the COD area sensor X. terminal INS
T is a terminal that outputs an integration start signal, and is
This outputs an integration start signal of "high" level and turns on switch elements SWa and SWb for a predetermined period of time.
By turning on the switch element S W a for a predetermined period of time, the initial voltage of the capacitor Ca is set to the power supply voltage VDD. Furthermore, by turning on the switch element SWb for a predetermined period of time, the initial voltage of the storage section of each pixel of the CCD area sensor is set to the power supply voltage VOO. Terminal I
NEN is a terminal for inputting an integration end signal, and when the voltage of the capacitor Ca discharged by the photocurrent of the monitoring light receiving element MPD becomes lower than the reference voltage Va after the switch elements SWa and SWb are turned off, the output of the comparator CMP becomes " The signal becomes "High" level, and this becomes the integration end signal. The terminal I NEND is a terminal that outputs an integration end signal, and the output of the comparator CMP is "High".
level or when a predetermined period of time has elapsed, the CC
A signal is output to stop the integration operation of D area sensor X. A microcomputer μ that controls this camera shake detection device BL
The flowchart of C2 is shown in Figure 21. A signal that changes from the "High" level to the "Low" level or from the "Low" level to the "High" level by the microcomputer μCL in the body is sent to the interrupt input terminal S of the microcomputer μC2.
When input to IINT, microcomputer μC2 executes the SIINT interrupt shown in FIG. First, #1001
Then, by detecting the level of the input terminal P1 of the microcomputer μC2, it is determined whether the interrupt input terminal SIINT is at the "Low" level. #1001 interrupt input terminal SII
If it is determined that NT is at the "High" level, the free run timer TA is stopped in #1002,
Assuming that the camera has finished photographing, the microcomputer μC2 is in a stopped state. If it is determined in #1001 that the interrupt input terminal SIINT is at the "Low" level, #10
Start the free run timer TA at 03. This free-run timer TA continues to operate without stopping until the camera finishes shooting. Then, assuming that the camera has started photographing, the flag DTP indicating data communication I is reset in #1004, and a subroutine for integral control of the CCD area sensor X is executed in #1005. Figure 23 shows the subroutine for the above integral control. When this subroutine is called, first, the integration start time is read from the free run timer TA, and the read time is set to A.
1, and the time A2L required from the previous integration end time to the current integration start time is A21 = A1 - A.
2 (#1150, #1151). Then, the terminal rNsT for outputting the integration start signal is set to ``High'' for a certain period of time.
h” level, switch elements SWa and S
Turn on Wb for a certain period of time and monitor light receiving element MPD
At the same time, the capacitor Ca discharged by the photocurrent is reset to the electric FA voltage VDD, and the storage section of each pixel of the two-dimensional CCD area sensor By setting the above switch elements SWa and SWb to the OF level,
Start the integration as F (#1152>. And,
Reset and start timer TB in #1155. #1160 waits for the terminal INEN, which detects the end of the integration, to become a "High" level, and when the terminal INEN becomes a "High" level, the integration is completed.
170, the terminal INEN becomes “Hi” at #1160.
If the level does not reach gh” level, wait for the timer TB to measure a predetermined time T1 in #1165, and then wait for the predetermined time T1
If 1 has elapsed, the integration should be finished.<Proceed to #1170, and if the predetermined time Tl has not elapsed, return to #1160. #1 At 170, the terminal I NEND is set to -IQ''H.
``high'' level, and transfers the charge in the storage section of each pixel in the CCD area sensor The previously calculated integration time A12 is stored as LA12 (#1 172, #1 174).Then, the current integration time A12 is calculated as A12=A2-Al, and the arithmetic mean TM12 of the current and previous integration times is TM12. =(A1 2
+LA1 2)/2 and return (#1 1
76, #1 178). The meaning of this operation will be explained later. When the integration of the CCD area sensor X is completed at #1005 in FIG. 21, charges are accumulated in the accumulation section of each pixel of the CCD area sensor X in accordance with the luminance of each pixel. Next, the microcomputer μC2 executes the data dump subroutine in #1007, dumps the charge information (11I worth of data) accumulated for each pixel of the CCD area sensor Convert to digital data and store in memory. Figure 24 shows this data dump subroutine. When the same subroutine is called, image data a(16, 11.) to a in the center of the screen among the image data input last time are
'(21.14) is rememorized as a(1.1) to a(64) and used as reference part data (#1180), and the current image data copied by A/D2 is a'(1. 1)
~a' (36.24) and use it as reference part data (#1185). FIG. 43 shows the reference part a (1.
1)~a(6.4) and reference part a'(1.1)~
a” (36.24>). After completing the data dump subroutine at 81007 in Figure 21, the microcontroller μC2 determines whether the flag DTP indicating data input is set at #1010. If the flag DTP is not set, return to #1005 and perform the integration and data dump again.If the flag DTP is set in #1010, the body It is determined based on the input data from the internal microcomputer μC1, and if the focus is not in focus, set the variable N to O, return to #1005, and perform the integration and data dump again (
#1015, #1020>. The reason why camera shake detection (image shake detection) is not performed when the camera is out of focus is that when comparing two images that are out of focus and out of focus, (i) Contrast is low, accurate image data cannot be obtained, and even if two images are compared, accurate camera shake detection cannot be performed. As a result, the accuracy of the amount of camera shake detected becomes low. (ii) When the photographing lens is driven to focus, the image changes, and image blur may be detected even though no image blur is actually caused by camera shake. This is because such problems arise. On the other hand, if the focus is #1015, the variable N is set to 1.
is added, it is determined whether this variable N is 2 or more, and if it is less than 2, the correction prohibition flag CI is set to prohibit camera shake correction.
Set F and proceed to #1005 (# 1 0 3
0~#1040). This is camera shake detection (image shake detection)
When performing this, it is necessary to have at least image data that will serve as a standard part and image data that will serve as a reference part, and for that purpose, the variable N
This is because must be 2 or more. If the variable N is 2 or more in #1035, the correction prohibition flag CIF is reset in #1050 to permit camera shake correction, and the subroutine for calculating the amount of camera shake is executed in #1055. Figure 25 shows the subroutine for calculating the amount of camera shake. When the same subroutine is called, first, the correlation function k=o,1,...,30.1=0.1,...,2
Calculate on 0 (#1200). This means that the image data a (i. Function d(.k,1
) as k=0.1,...30.1=0.1. ..., 2
By calculating with respect to 0, the image data of the reference part is compared while being shifted by one pixel in each of the horizontal and vertical directions with respect to the reference part. Next, find the minimum value of the correlation function cl (kJ) and find the shift amount (k, 1) that gives this minimum value (#1205). As shown in the figure, the shift amount (k, l) when matching the image data of a partial area of the same size at the center of the reference part is (1 5.1
0). Therefore, the image data a(i.
The deviation direction (vector) when j) matches the image data of a partial area of the same size at any position of the reference part is Δk, Δ1>= (k, t') - (1 5.,
1 0 ), and the deviation amount is P=(Δk2+
Calculated as Δ12)+72 (#1210.41M
215). After the above calculations, read the calculation end time from the free run timer TA, store the read time as A3, and start from the integration end time A2 to the calculation end time A3.
Calculate the time A23 from the previous calculation end time LA3 to the current integration start time A23 = A3 - A2.
Find the time A31 until 1 (#1 2 20~#1
230). Then, it is determined whether N=2 or not, and if N=2, the time T from the previous integration center to the current integration center
is calculated as T = TM1 2 + A2 1, and if N = 2, then calculated as T = TM12 + LA23 + A31 (#1 2 3 5 to #1245). This time T will be explained based on FIG. 44. First, N=
2, as can be seen from the flowchart in Figure 21, integration, data dump, integration, data dump, and calculation are performed, and the time T from the previous integration center to the current integration center
It can be seen that is between t1 and t2 in FIG. The time t1 at which the image of the previous integration is formed is set as the center of the previous integration, and the time from there to the end of the previous integration is (LA2
LAI)/2=LA1 2/2. In other words, it is half of the previous integration time. The time of the last data dump is A
2 1 = A 1 - LA2 (A2 in the flowchart)
becomes. The time point t when an image is formed by the current integration is set as the center of the current integration, and the time from the start of the current integration to the current integration center L2 is half the current integration time A 1 2/
2 = (A 2 - A 1 )/2. therefore,
The time T from the previous integration center to the current integration center is T
-(Al 2+LA1 2)/2+A21=TM12+
It will be A21. Next, when N>2, the time required for calculation and the time required for data transfer (the time for outputting data from the microcomputer μC2 of the camera shake detection device BL to the microcomputer μC1 in the body) are always included, so from the previous integration center to the current time The time T to the center of integration is between t2 and t in Fig. 14, and T=(LA2-LAI)/2+(LA3-LA2
)+(Al-LA3)+(A2Al)/2=TM1 2
+LA23+A3 becomes 1. Next, the microcomputer μC2 divides the amount of camera shake P obtained as described above by the time interval for obtaining image data for camera shake detection, and calculates the amount of camera shake per unit time, that is, the camera shake speed Q=P/T. demand(#
1255). Then, set the previous calculation end time A3 to LA3.
Store the time A23 from the previous integration end time A2 to the calculation end time A3 as LA23, and return (# 1 2 60, # 1265).
．． After completing the subroutine for calculating the camera shake amount in #1055 of FIG. 21, the microcomputer μC2 determines in #1060 whether the interchangeable lens is the camera shake correction lens NBL. If the interchangeable lens is not a camera shake correction lens in #1060, a subroutine for camera shake determination is executed in #1070 to determine whether there is a risk of camera shake;
Return to #1005. On the other hand, if the interchangeable lens is an image stabilization lens in #1060, the process proceeds to #1075.
In #1075, the terminal CSBL is set to ``Low'' level, and an interrupt is made to the microcomputer μC1 in the body for data transfer.Then, in #1080, the subroutine for data communication ■ is executed, and the 6-byte data ( Displacement amount Δk,
Δe, camera shake warning signal, integration time TI, camera shake speed Q,
The correction start signal and the sum T of the integration time and calculation time are output to the microcomputer μCl in the body. After that, in #1085, the terminal CSBL is set to ゜'High'' level, and the process returns to #1005.Next, the subroutine for camera shake judgment is shown in Fig. 26.When the subroutine is called, first, the camera shake speed Q is changed to the exposure time. Multiply by T s (real time) to get this value Q
Determine whether XTs is less than the predetermined value K1 (#1280
), here, the reason why the camera shake speed Q is multiplied by the exposure time Ts is because the longer the exposure time Ts, the greater the amount of camera shake. If it is less than the predetermined value K1, reset the flag WNGF for warning of camera shake, and if it is greater than or equal to the predetermined value K1, set this flag WNGF and return (#1285, #1290>. Note that if the interchangeable lens does not shake If it is a correction lens, the microcomputer μC inside the lens
3 performs camera shake detection and image stabilization, and sends a signal to the body indicating whether or not a camera shake warning exists. This point will be discussed later. Next, from the camera shake detection device BL to the microcomputer μC1 in the body.
This section explains the operation of data transfer to . The in-body microcomputer μC1 detects that the terminal CSBL of the camera shake detection device BL is “
When a signal changing from "High" level to "Loud" level is received, the interrupt DEINT shown in FIG. Input the 6-byte data sent from the detection device BL. Then, #94
Step 5 determines whether the interchangeable lens is an image stabilization lens NBL, and if it is an image stabilization lens, step #9
Execute the subroutine for lens communication B in step 50, and if it is not an image stabilization lens, skip step #950.
Return each.

The subroutine for data communication (2) with the above-mentioned camera shake detection device BL is shown in Fig. 20. When the same subroutine is called, the microcomputer μC1 in the body also sets the terminal CSBL to “Low”.
" level, the microcomputer μC1 in the body outputs the evening lock for serial communication, and in synchronization with this, inputs 6 bytes of data serially output from the microcomputer μC2 of the camera shake detection device BL, and sets the terminal CSBL to " High”
Return as level (#9 6 0 to #97
0). Next, the subroutine for lens communication B described above is executed in the seventh step.
It is shown in the figure. When this subroutine is called, the in-body microcomputer μC1 sets the terminal CSLE to “Low” level to indicate communication with the lens, and first
Serial communication is performed in which byte data is input from the lens side and 2 bytes of data are simultaneously output, then 7 bytes of data are output and terminal CSLE is set to ``H''.
``high'' level to finish the data transfer (#1
8 5~#197). As for the above 7 bytes of data,
Image stabilization amount Δk. 8e, presence/absence of image stabilization start signal, end signal, release signal and microcomputer stop signal, control shutter speed, CCD in image stabilization detection device BL
Area sensor integration time TI, image blur movement speed Q,
Then, there is the sum T of the integration time and calculation time of the COD area sensor. Next, a flowchart for controlling the microcomputer μC3 in the lens (particularly lens control for image stabilization) is shown in Figures 28 to 28.
It is shown and explained in Fig. 33. The lens is attached to the body,
The lens attachment detection switch sLε changes from ON to OFF, or the voltage VD supplied to the lens from the body
D rises above the operating voltage, and the reset circuit REI
When C is detected, a signal that changes from the "Los" level to the "High" level is input to the reset terminal RE3 of the lens microcomputer μC3, and the lens microcomputer μC3
C3 executes the reset routine shown in FIG. 28, resets the ports and registers, and then stops. In addition, when an interrupt occurs from a stopped state, clock oscillation is automatically started by the oscillator built into the microcontroller μC3, and when transitioning from an operating state to a stopped state, clock oscillation is automatically stopped. This is what we do. When a signal changing from the "High" level to the "L01 level" is input from the body microcomputer μC1 to the terminal CSLE of the lens microcomputer μC3, the interrupt routine LCSINT shown in FIG. 29 is executed. Byte data is input and output, and from the body status ICPB obtained from this data communication, it is determined whether lens communication A is successful or not. If lens communication is A, 5 bytes of data are synchronized with the serial communication clock. It outputs and waits for an interrupt (#L5 to #L15).If the lens communication is not A in #L10, it is determined that it is lens communication B, and the process goes to #L11, inputs 6 bytes of data, and enters the microcomputer μC3. Determine whether or not a stop signal is set, and if so, stop (#L11.#L
12). If the stop signal of the microcomputer μC3 is not set, the process advances to #L13 and it is determined whether or not the release has ended. The signal for determining whether or not the release is complete is as follows:
Lens communication B at the end of release (#1325 described later)
(see) is input from the microcontroller μC1 in the body.
If the release is completed in #L13, the flag RLF indicating that the release is in progress is reset in #L14, and the driving subroutine is executed in #L15 in order to return the lens that has been moved for image stabilization to its initial position. Executes and waits for an interrupt. If the release does not end at #L13, #L25 is set to perform image stabilization at the shooting distance before starting exposure.
In #L25, the timer TC is reset and started, and in #L30, the integral time TI is half TI/2.
Set the timer interrupt to occur. Figure 3.0 shows the timer interrupt enabled by #L30. In this timer interrupt, the counters C Tk and C Tl indicating the lens position are read, respectively, and Nk1 and N11 are read.
After storing it in memory, return (#L105, #
L110). The counters CTk and C'1 are designed to count up when the pulse motors M3 and M4 for driving the image stabilization lens rotate in the normal direction, and count down when they rotate in the reverse direction. An internal hard counter counts the pulses that μC3 outputs to drive the lens drive amounts ΔNk and ΔN1. This timer interrupt is half of the integration time TI (T
I/2), so (Nkl, N11) indicates the lens position at the center of integration. and,#
At L40, it is determined whether or not to start correction. The signal for determining whether or not to start this correction is input from the microcomputer μC1 in the body in lens communication B. If correction starts at #L40, #L45 and #L50 indicate the lens position of the center of integration. Set the variables Nkl and NII to 0, and if the correction is not to start, skip #L45 and #L50 and proceed to #L55. In #L55, the camera shake detection calculation end time is determined from counters CTk and CT1 that indicate the lens position. Read the count values indicating the lens position and store them as Nk2 and N12 respectively, and calculate the lens movement amount from the center of integration to the end of camera shake detection calculation as Nk = Nk2 - Nk
l, N1=N12-N11 (# L 5 5
~#L70). Then, from the input data Δl and Δk indicating the amount of camera shake, the lens driving amount ΔNl required for camera shake correction is determined.
, ΔNk, respectively, and subtract the lens movement amounts Nk, Nl from the above-mentioned center of integration to the end time of camera shake calculation to find the actual lens drive amounts ΔNk, ΔNl (#
L75~#L90). FIG. 45 is a graph showing the amount of camera shake and the amount of drive of the camera shake correction lens. In the figure, B1 is camera shake iP, and L
L indicates the lens drive amount to correct this.
The shaded area sandwiched between the lines Bl and LL is the amount of camera shake caused by driving the camera shake correction lens. I 1, I 2, I 3, I 4,...
indicates the integration time, and Cl, C2, C3, C4,... indicate the calculation time. In the l-th camera shake detection, calculation time C1
As a result of the calculation, the amount of camera shake obtained (ΔNk, ΔN1)
is the amount of camera shake at the center of the first integration. Based on this, the camera shake correction lens is driven. The second integral is
It is performed after calculation time C1. The camera shake amount (ΔNk, ΔNl) obtained by the second calculation is calculated based on the lens position (Nk
1, N11). The lens position at the end of the second calculation time C2 is (Nk2, NN2
), the lens (7) drive amount (Nk2-Nkl.Nl2-Nl1> that moved from the center of integration of the second integration time I2 to the end of the calculation time C2) is expressed as the amount of camera shake (
The actual lens drive amount is what is subtracted from ΔNk, ΔNl). The microcomputer μC3 then executes a subroutine for determining camera shake (#L95). This is shown and explained in Figure 31.
In this subroutine, the lens position to be driven next is set to N.
Calculate by k3=Nk2+ΔNk, Nf3=Ne2+ΔN1 6 (#L150, #L155). Soshite, sono absolute value I
G k where Nk3 1 and l Ne3 1 are the physical correction limit values (the limit at which the correction lens hits the lens barrel), respectively.
, determine whether the value exceeds the value obtained by adding the allowable value ε to G L (#L 1 6 0, # 1 6 5). If either of the absolute values I Nk3 1 and l NN3 1 exceeds a predetermined value, the process proceeds to #L19B. On the other hand, #L160
, #L170, if both the absolute values I Nk3 1 , l Nt3 do not exceed the predetermined values, the previous integration time and calculation time are used as the reference amount δ for which each correction amount ΔNk and ΔNl moves per unit time. (Assuming that the brightness is almost the same as the previous time, the calculation time is constant.) Determine whether the value exceeds the value multiplied by the sum T (#L170.
). If the correction amount ΔNk or ΔNN exceeds δ×T, it is determined that camera shake correction cannot be performed sufficiently, and the process proceeds to #L185. In #L185, it is determined whether the value obtained by multiplying the camera shake speed Q by the actual shutter speed time Ts is less than the reference value KTH. This is because even if the measured camera shake speed Q is large, if the actual shutter speed time Ts is short, the amount of camera shake will be small, so in this case the camera shake warning is not issued, #L185. Hand shake jL
If QXTs is less than the reference value K'TH, or #
At L170 and #L175, the correction amounts ΔNk and ΔNl are δ×T
If it is below, the process advances to #L187 and it is determined whether the flag RLF indicating that the release is in progress is set. If the flag RLF is set in #L187, the process returns immediately. This is to prevent the warning signal once set during release from being reset. On the other hand, if the flag RLF is not set, it is assumed that the release is not in progress, and a warning signal indicating that camera shake is occurring (or cannot be fully corrected) is reset (#Ll88).Next, in #L189, the release signal is Determine whether or not is being sent from the camera. If the release signal has not been sent, a flag RLF indicating this is reset, and if it has been sent, the flag RLF is set, the warning signal is reset, and each process returns (#L189 to #L192). This is to newly detect whether or not camera shake has occurred during shooting. In #L185, if KT}I≦Q Determine, if set, return, if not set, #
Proceed to L189 (#L193, #L194). After executing the camera shake determination subroutine at #L95 in FIG. 29, the microcomputer μC3 in the lens executes the lens drive subroutine for camera shake correction at #L100, and enters a state of waiting for an interrupt. This lens drive subroutine is shown in Figure 32. The lens drive motors M3 and M4 for image stabilization are pulse motors as described above.
The microcomputer μC3 inside the lens sends one pulse instructing forward or reverse rotation to drive the lens one step. first,
The in-lens microcomputer μC3 sets a flag MOVF indicating that the lens is being driven in the lL200"C"l direction. Next, the absolute value 1ΔN of the lens drive amount in the k direction
Determine whether kl is 0 or not, and if the absolute value 1ΔNkl is not 0, determine whether ΔNk is positive or not. If it is positive, it outputs one driving pulse in the forward rotation direction, and if it is not positive, it outputs one driving pulse in the reverse direction, subtracts 1 from lΔNkl, and sets it as a new IΔNkl (# L 2 0 5~#L
225). If the absolute value 1ΔNkl is 0 in #L205, it is assumed that lens driving in the k direction has ended, and #L2 5
5, it is determined whether the flag MOVF indicating that the lens is being driven in one direction has been reset. If the flag MOVF has been reset in #L255, it is assumed that lens driving in the direction e (described later) has also been completed, and the process returns. If the flag MOVF has not been reset, the process advances to #L230.

Also, proceed to #L230 from #L225. #L230
~ #L250, the absolute value of the lens drive amount in one direction {
It is determined whether ΔNil is O or not, and if the absolute value IΔN11 is not 0, it is determined whether ΔNl is positive or not. If it is positive, one pulse is applied in the forward direction, and if it is not, it is Output one driving pulse, subtract 1 from 1ΔNl+, and make a new 1ΔN11. At #L230, the absolute value is 1Δ
If Nll is 0, it is assumed that the lens driving in one direction has been completed, and the process proceeds to #L260, where the flag M○VF indicating that the lens is being driven in the l direction is reset, and #L20
Return to 5. Also, return to #1205 from #L250. Next, the subroutine for lens drive (2) is shown in Figure 33.
First, the microcomputer μC3 in the lens sets a flag MOVF indicating that the lens is being driven in the e direction at #L300. Next, it is determined whether the absolute value lcTkl of the lens position in the k direction is O, and the absolute value lcTkl is 0.
If not, determine whether CTk is positive or not, and if it is positive, output one drive pulse in the reverse direction, and if not, output one drive pulse in the forward direction, subtract 1 from lcTkl, Newly set as lcTkl (#L305 to #L32
5). #If the absolute value 1cTkl is O in L305, then k
Assuming that the lens position in terms of direction has returned to its initial position,
Proceed to #L 3 3 0 and determine whether the flag MOVF indicating that the lens is being driven in the e direction has been reset. If the flag MOVF has been reset in #L330, the lens position in one direction (described later) has also returned to the initial position, and the process returns. Flag MOVF
If has not been reset, proceed to #L335. Further, from #L325, the process also advances to #L3 3 5.

In #L335 to #L355, it is determined whether the absolute value 1cTII of the lens position in the l direction is O, and the absolute value l
cTI! If l is not O, it is determined whether CTt' is positive or not, and if it is positive, it outputs one drive pulse in the reverse direction, and if it is not, it outputs one drive pulse in the forward direction, and Ic
Subtract 1 from II to create a new 4,:lcrt'l.
Absolute value 1cTj at #L335! If l is 0, the lens position in one direction is assumed to have returned to the initial position, and #L
The process advances to #360, resets the flag MOVF indicating that the lens is being driven in the e direction, and returns to #L305. Also, return to #L3 0 5 from #L355. This causes the lens to be driven in the opposite direction by the amount that was being driven to correct camera shake, and reset the camera shake correction lens to its initial position. The above is the control related to camera shake detection and camera shake correction. Returning to the flow of the in-body microcomputer μC1 in FIG.
After outputting the data to L, the display data is output to the display control circuit DI SPC by serial communication in #55.
Display data includes shutter speed TV, aperture value AV
, shooting mode (normal mode, portrait shooting mode, landscape shooting mode), and presence/absence of camera shake. When camera shake occurs, the display control circuit DISPC performs display control so that the shutter speed TV display blinks. This display is shown in Figures 46 and 47. In the figure,
a, b, and c are shooting mode displays, respectively indicating normal mode, portrait shooting mode, and landscape shooting mode.
Only the selected mode is displayed. d and e indicate the shutter speed and aperture value, respectively, and the flashing shutter speed display d warns that camera shake is occurring. f and g indicate the aperture value and shutter speed displayed in the viewfinder, and the flashing shutter speed display g warns that camera shake is occurring. After outputting the display data in #55, the in-body microcomputer μC1 turns the release switch S2 ON/OFF in #60.
Determine F. #60 Release switch S2 is OFF
If so, it is determined in #130 whether the photographing preparation switch S1 is ON.

If the shooting preparation switch S1 is ON in #130, #1
Execute the process from step 5. Release switch S with #60
If 2 is ON, it is determined in #62 whether or not the camera is in focus. If the image is not in focus in #62, the process starts from #15. If the camera is in focus in #62, the shutter is released in #65, and waits for the mirror up to be completed in #70. When the mirror up is completed, the exposure control subroutine is executed in #75. This exposure control subroutine is shown in Figure 27. When this subroutine is called, first the internal microcontroller μ
Cl determines whether or not flash photography is being used. If flash photography is being used (FLF = 1), the terminal FLOK is set to the "'High" level, and the film sensitivity SV data is sent to the built-in microcomputer μC1 in the body. Output to the D/A converter (# 1 3 00 - # 1302). As a result, the D/A converter converts the film sensitivity S■ data into an analog signal and outputs it to the dimming circuit STC.

The light control circuit STC integrates the reflected light from the film surface substantially in synchronization with the flash emission, and outputs a light emission stop signal STP to the flash circuit FLC when a predetermined amount of light is integrated. The configuration of this flash circuit FLC is shown in Figure 40. In the figure, DD is a booster circuit consisting of a DC/DC converter, and has a low DC voltage V. o0 is boosted to a DC high voltage and connected to a capacitor MC for storing luminous energy via a rectifying element DS.
The EMC is a light emission control circuit, and the flash light is emitted by an AND signal between the 'signal (FLOK's High' level) output during flash photography and the X signal that turns ON when the first act is completed. The light emission is stopped in response to the light emission stop signal STP.

Return to the flow in Figure 27 and start from #1302 or #
When flash photography is not being performed at 1300, the process proceeds to #1303, where a count value corresponding to the shutter speed (exposure time) is preset in the exposure time counter, the magnet for one-curtain running is released, and one-curtain running is started; Start the exposure time counter (#1 3 0 3 to #13
10). Then, it waits for the counter to finish counting, and when it finishes counting, it waits for a certain period of time, and then connects the terminal FLOK to the terminal FLOK for the time required from the start of second-act running to the completion of running.
It is set to Low level, executes the lens communication B subroutine, and notifies the lens internal circuit LE that exposure has been completed (#1 3 1 5 to #1325). At this time, a correction completion signal is sent to the lens side. Next, lens communication A
Execute the subroutine and input data for camera shake detection (#1330). Next, output a signal that changes from the "Los" level to the "High" level to the terminal SIINT of the microcomputer μC2 of the camera shake detection device BL. Then, after detecting camera shake, the process returns (#1335). The circuit configuration for controlling the exposure time is shown in FIG.

The exposure time counter CNTR is controlled by the microcomputer μC1 in the body.
When a count value indicating the exposure time is preset to the reset terminal PS from the terminal ST and a start signal is input to the terminal ST, the clock φ input to the clock input terminal CK is counted. When the count value of the exposure time counter CNTR reaches the preset value, a count-up signal is output from the terminal CU, and the magnet 2Mg for running the second curtain is separated, causing the second curtain to run. Here, the reason why the exposure time is controlled by hardware is that there is an interruption from the camera shake detection device BL during exposure, and control (data communication with the lens) is performed using this interruption. After completing the exposure control subroutine at #75 in Figure 5, the microcomputer μC1 in the body controls the winding by one frame at #80. Then, it is determined based on the data from the lens, and if it is not a camera shake correction lens, it is determined based on the data from the camera shake detection device BL (#
9 0 >. If there is camera shake, set warning display data in #95, and if there is no camera shake,
In #100, display data with no warning is set, and in #102, the display data is output to the display control circuit DI SPC for display. Next, in #105, it is determined whether the photographing preparation switch S1 is turned on, #1
If the shooting preparation switch S1 is ON in 05, #9
Proceed to 0, press #105 or #130 to press the shooting preparation switch S
1 is OFF, the power supply transistors Tri, Tr
2 to ○FFL, display erase data to display control circuit DI
Output to the SPC to erase the display, set the OFF signal of the microcomputer μC3 in the lens, execute the lens communication B subroutine, and stop (#1 1 0 to #12
5). [Effects of the Invention] As described above, in the present invention, when the shutter speed calculated based on the output of the photometry means during flash photography is equal to or less than a predetermined shutter speed that is smaller than the maximum flash synchronization speed, Since the shutter speed for control is set to the predetermined shutter speed, it is possible to prevent the shutter speed from becoming excessively slow during slow synchro photography. Note that if a means for detecting and correcting camera shake is provided, the lower limit value of the shutter speed during slow synchronization shooting can be set to a small value. In this case, if the camera shake correction is determined to be effective or not, and if it is determined that the image stabilization is not effective, the shutter speed is set to the maximum flash synchronization speed. This prevents the shutter from being used.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the basic configuration of the present invention, FIG. 2 is a circuit diagram of a camera as an embodiment of the present invention, FIG. 3 is a circuit diagram of a circuit inside the lens used in the same, and FIGS. FIG. 33 is a flowchart for explaining the operation of the same as above, FIGS. 34 to 36 are AE program diagrams used for the same, and FIG.
38 is a circuit diagram of the white balance circuit used in the above, FIG. 39 is a circuit diagram of the shutter control circuit used in the same, and FIG. The figure is a circuit diagram of the flash circuit used in the above, Figure 41 is an explanatory diagram showing the shooting screen of the same, Figure 42 is a circuit diagram of the camera shake detection device used in the same, and Figure 43 is the CCD area sensor used in the same. FIGS. 44 and 45 are explanatory diagrams showing the configuration of the above device, and FIGS. 46 and 47 are diagrams showing the display state of the display unit used in the above camera. 1 is a photometering means, 2 is a flash photography determining means, 3 is a shutter speed calculating means, 4 is a shutter speed limiting means, 5
6 is a camera shake detection means, 6 is a camera shake correction means, and 7 is a determination means.

Claims (2)

[Claims] (1) A photometering device that measures the brightness of a subject, a flash photography determination device that determines whether or not flash photography is being used, and a shutter speed calculation device that calculates the shutter speed for flash photography based on the output of the photometry device; An exposure control device comprising: shutter speed limiting means for setting a control shutter speed to the predetermined shutter speed when the calculated shutter speed is less than or equal to a predetermined shutter speed smaller than a maximum flash synchronization speed. (2) A camera shake detection device that detects the amount of camera shake; a camera shake correction device that drives a part of the photographic lens to correct camera shake based on the detection output of the camera shake detection device; and a camera shake correction device that determines whether the camera shake correction is effective. and determining means, the shutter speed calculation means sets the shutter speed to the maximum flash synchronization speed when the determination means determines that the correction is not effective, and sets the shutter speed to the maximum flash synchronization speed when the determination means determines that the correction is effective. 2. The exposure control device according to claim 1, further comprising means for calculating a shutter speed based on the output of the exposure control device.