JPH08234300A - Compound camera - Google Patents

Abstract

(57) [Summary] [Purpose] To perform appropriate focus adjustment when shooting still images during video shooting with a compound camera. [Structure] In a compound camera 50 having a still camera section 51 and a video camera section 52, the focus detection means 54 is
The focus of the taking lens 53 is detected to obtain the defocus amount. The control means 56 obtains a lens drive amount for obtaining a focused state based on the obtained defocus amount and controls the lens drive means 55. When performing still shooting during video shooting, focus control suitable for still shooting is performed at high speed by driving the lens during a release time lag in a short time. [Effect] Good focusing accuracy can be obtained without increasing the release time lag, and the lens driving sound can be reduced in a short time, which can be substantially reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compound camera in which a still camera and a video camera are integrated by using a common taking lens.

[0002]

2. Description of the Related Art Conventionally, a composite camera in which a still camera for performing still photography using a silver salt film and a video camera for performing video photography using magnetic tape are housed in a single housing together with a common photographing lens, A compound camera has been proposed in which the viewfinder of a single-lens reflex still camera is replaced and a video camera unit is attached.

Japanese Patent Laid-Open No. 63-247738 discloses a compound camera in which the still camera section and the video camera section share the means for focus adjustment and exposure control. Also, in order to share the shooting lens, the light flux from one shooting lens is split by a half mirror, and one is guided to the silver salt film and the other is guided to the image sensor of the video camera section. Japanese Patent Application Laid-Open No. Sho 59-180566 discloses that the same angle of view is used for video shooting.

Further, Japanese Patent Application Laid-Open No. 62-263728 filed by the applicant of the present invention discloses focus detection a plurality of times in the past in order to perform good focus adjustment on a moving subject during still image capturing. A predictive control technique has been disclosed in which a tracking delay amount of a lens caused by movement of a subject is predicted and calculated based on the result, and the lens is corrected and driven according to the calculated value.

In the above-described predictive control, AF, which is the time required from the start of focus detection to the end of lens driving during still shooting,
Time lag and trigger switch (release switch)
Predictive calculation is performed to eliminate the tracking delay (focus shift amount) that occurs when the subject moves during both the release time lag, which is the time from when the is turned on to the exposure of the film, and the time lag. I am trying to adjust the focus. By performing such predictive control, it is possible to take a photograph with good focus during still photography.

Further, Japanese Patent Application Laid-Open No. 54-86325 discloses a technique for reducing the driving noise of the lens by driving the lens at low speed during video recording.

[0007]

In the above-mentioned compound camera, when performing still shooting during video shooting, when the focus adjustment control is different between video shooting and still shooting, the lens is used during still shooting by the shift. It becomes necessary to perform the correction drive of. In such a case, if the lens is driven at a low speed during still photography as in the conventional example, the time required for the correction driving becomes long, which causes a long release time lag and deteriorates the usability of the camera, and the shutter. There is a problem of missing opportunities. Further, if the release time lag is set to the same value as the conventional one, sufficient correction drive cannot be performed, and there is a problem that a photograph with a defocus is taken.

The present invention has been made in order to solve the above problems, and can appropriately perform focus adjustment without increasing the release time lag when performing still shooting during video shooting in a compound camera. The aim is to get a compound camera.

[0009]

According to the present invention, a still camera unit for performing still image capturing, a video camera unit for performing video image capturing, and image capturing including a focus lens commonly used by the still camera unit and the video camera unit. In a compound camera having a lens, focus detecting means for detecting a focus state of the focus lens to obtain a defocus amount, lens driving means for driving the focus lens, and defocus obtained by the focus detecting means. And a control unit for controlling the lens driving unit according to the lens driving amount to obtain a lens driving amount for obtaining a focused state on the basis of the amount. When the still shooting is performed during the above video recording, the release time lag will occur during the video recording. It is characterized by performing the focus adjustment control for still photography.

[0010]

According to the present invention, when still photography is performed during video photography, appropriate focus adjustment control can be performed without particularly increasing the release time lag. That is, for example, the lens drive for focus adjustment during video shooting is driven at a low speed, and the correction drive for correcting the shift amount of the focus adjustment control is performed during the release time lag when performing still shooting during video shooting. When performing the correction driving, the lens can be driven at a high speed to complete the correction driving within a short release time lag. By this, without increasing the release time lag,
The correction driving can be completed, and it is possible to prevent a photo opportunity from being missed and a photograph out of focus. Further, when the lens is driven at a high speed, noise also increases, but since the driving time is short and the release operation sound for still photography overlaps, it is not a serious problem.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 is a block diagram conceptually showing the present invention. In FIG. 1, reference numeral 50 denotes the entire compound camera. Reference numeral 51 is a still camera unit for performing still photography, 52 is a video camera unit for performing video photography, 53 is a taking lens common to the still camera unit 51 and the video camera unit 52, and 54 is a taking lens 5.
The focus detection means for detecting the focus of 3 to obtain the defocus amount, 55 is a lens drive means for driving the focus lens in the photographing lens 53 in the optical axis direction, and 56 is based on the defocus amount obtained by the focus detection means 54. Is a control means for controlling the lens driving means 55.

Next, the operation of the above configuration will be described. When performing still shooting, the still camera unit 51 shoots a subject image from the shooting lens 53 and exposes it on a silver salt film. Further, when video shooting is performed, the video camera unit 52 converts the image from the shooting lens 53 into a video signal by the solid-state image sensor and records it on a magnetic tape.

The control means 56 controls focus adjustment differently between video shooting and still shooting. If still shooting is performed during video shooting, focus adjustment control for still shooting is performed during the release time lag. At that time, control is performed so that the lens is driven at a low speed during video shooting and the lens is driven at a high speed during the release time lag.

Next, a detailed description will be given according to each embodiment. FIG. 7 is a left side sectional view showing the structure of the compound camera according to the present invention. In FIG.
Is a lens unit for capturing images on silver salt film,
Reference numeral 3 is a lens barrel for holding the lens element and constituting the lens unit 2, 4 is a diaphragm for still photography, and 5 is a silver salt film. In this embodiment, the lens unit 2 is a zoom lens, and is driven by information from a variable power lens element group that can move on the optical axis in conjunction with an automatic or manual zoom operation, and information from an automatic focusing device described later. It has a focusing lens element group.

A shutter device 6 is arranged immediately in front of the silver salt film 5, and is a shutter curtain 6a supported by a supporting portion 6b.
The silver salt film 5 is exposed by opening and closing. Reference numeral 7 denotes a semi-transparent thin film mirror for distributing a light flux forming a subject image emitted from the lens unit 2 to a silver salt film 5 side and a solid-state image sensor 13 side described later, and 7a denotes an optical axis emitted from the lens unit. , 7b are optical axes that pass through the semitransparent thin film mirror 7 and reach the silver salt film 5, 7c, 7b.
Reference numeral d denotes an optical axis that reaches the solid-state image sensor 13 after being reflected by the semitransparent thin film mirror 7. Reference numerals 8a and 8b are field lenses for aligning the exit pupil of the lens unit 2 with the entrance pupil of the reduction lens unit 10, 9 is a reflection mirror for deflecting the photographing optical axis 7c, and 10 is an optical axis 7.
It is a reduction lens unit provided on d and includes a video aperture unit 11 for video shooting inside. Reference numeral 12 is an optical low-pass filter, and 13 is a solid-state image sensor such as a CCD. An aerial image 40 is formed at a position equivalent to the silver salt film 5, and is re-formed on the solid-state image pickup device 13 via the reduction lens unit 10.

Reference numeral 14 denotes a sub-mirror disposed behind the semi-transparent thin film mirror 7 and capable of retracting at the time of still image pickup, and guides a part of the image pickup light to the focus detection device 15. The focus detection device 15 in the present embodiment uses a conventionally known phase difference detection method, detects the positions (phases) of two images generated by the light flux that has passed through two different regions of the photographing lens, and detects that position. The defocus amount and the direction on the film surface are calculated from the phase difference.

Reference numeral 16 is a light shielding plate for protecting the shutter curtain 6a from the light flux transmitted through the semitransparent thin film mirror 7 and for preventing light leakage, which is retracted during film exposure.
Reference numeral 17 denotes a back lid unit that holds the silver salt film 5 when it is loaded, and is opened and closed when the film is taken out and loaded. An electronic viewfinder unit 18 outputs an image to a small liquid crystal 79 to monitor the image signal from the solid-state image pickup device 13, and the reflection mirror 2
Observe through 0 and the eyepiece 21. The electronic viewfinder unit 18 is rotatable about a rotary shaft 22 as a spindle.

In this embodiment, during video shooting,
The still shooting diaphragm 4 is always maintained in the open state, and when a still shooting release switch, which will be described later, is pressed, the diaphragm 4 is stopped down to a predetermined aperture value. Therefore, during video shooting, exposure control is performed only by the video aperture unit 11 in the reduction lens unit 10, and the accumulation time of the solid-state image sensor 13 and the gain of the signal processing system are changed as necessary to obtain a video signal of an appropriate level. I am trying.

Next, reference numeral 23 denotes a secondary battery which is detachably attached to the lower part of the compound camera, and which is a power source for supplying electric power to each part. In front of this lens unit 3, an openable and closable barrier 25 incorporating a strobe is provided, and also serves as an interface with an external device such as a microphone 26 for recording audio during video shooting and a television or a stereo device. External terminals 27 and the like are provided.

FIG. 8 is a top view of the compound camera. 28 is a cartridge chamber of the silver salt film 5, and 29 is the silver salt film 5.
It is a spool chamber for winding up. In this embodiment, a prewind method is adopted in which the film is loaded up to the spool up to the last frame in advance and the exposed frame is sequentially rewound into the patrone during shooting.

Reference numerals 30 and 31 are a zoom driving motor and a focus driving motor of the taking lens. Reference numeral 32 is a zoom button arranged at a position that can be operated by the photographer's right hand, 33 is a main mode selection switch that also serves as a power switch, 34 is a trigger button for video shooting, and 35 is a silver salt film 5. It is a release button for still photography. On the side opposite to each of the above operating members, it is possible to select and use in common with both video shooting and still shooting such as program exposure mode, portrait mode with many open apertures, sports mode with shutter speed priority, backlight compensation mode, etc. A shooting mode selection dial 36 is provided.

In the present embodiment, photometry calculates the brightness of the subject from the output signal level of the solid-state image pickup device 13 and the aperture value of the video aperture unit 11. The solid-state imaging device 13 is electrically divided into areas, and backlight detection is performed from the luminance signal of each divided area.

Next, 37 is a video tape cassette housing portion arranged on the right side of the lens unit 2. In this embodiment, a video tape having a tape width of 8 mm is used as a recording medium. The cassette housing portion 37 has a recording / reproducing mechanism including a magnetic head cylinder, a capstan, a pinch roller, etc., and a control panel 38 for performing operations such as recording / reproducing of a video tape on its upper surface.
An eject button 39 for ejecting the videotape and loading the videotape is arranged.

FIG. 9 is a block diagram showing the configuration of the electric circuit of this embodiment. The camera microcomputer 41 controls AF, zoom, release operations, and the like, and accepts and controls the release operation and mode setting of the camera body. Mode microcomputer 4
2. The video signal processing board 4 with the mechanical microcomputer 43 that controls the recording / playback of the video tape and the servo mechanism as the core.
4, an audio signal processing board 45, a flash board 46, a power board 47, and various operation switches and sensors are provided.

FIG. 2 is a flow chart for explaining the operation of the entire compound camera according to the first embodiment of the present invention.
When the main mode selection switch 33 of FIG. 7 is operated and the power of the camera is turned on, the camera control is performed as follows according to the programs stored in the ROMs of various microcomputers 41, 42 and 43 for controlling the camera. Is performed.
When the power of the camera is turned on, the process proceeds to step S2 via step S1. In step S2, the state of the video standby switch (not shown) is detected, and when the video recording standby operation is performed (ON state), the process proceeds to step S3, and otherwise, step S3.
It stands by at 2 and continues to detect the status of the video standby switch.

In step S3, the brightness of the copy is calculated from the output signal of the solid-state image pickup device 13 and the aperture value of the video aperture unit 11, and an appropriate exposure is performed based on the subject brightness and the sensitivity of the loaded silver salt film 5. The shutter speed and aperture value for performing the calculation are calculated and stored in a predetermined area of the RAM. In step S4, the line sensor of the focus detection device is controlled to capture the image signal. In the following step S5, the lens unit 2 is obtained from the image signal obtained in step S4.
Calculate the defocus amount of. In step S6, the flag LSP for controlling the lens driving speed is set to L for low speed control.
Set to. Then, in step S7, step S5
The focusing lens is driven so as to eliminate the defocus obtained in. At this time, the flag L is set in step S6.
Since SP is set to L, the lens is driven at low speed.

In step S8, the state of the trigger button 34 for starting and stopping the video recording is detected. If the trigger button 34 is in the on state, the process proceeds to step S9. If not, the process returns to step S2. Step S
At 9, it is determined whether or not the video recording operation is being performed. If the video recording operation is being performed, the process proceeds to step S10, and if not, the process proceeds to step S11. If the process proceeds to step S10, the recording operation is stopped in step S10, and if the process proceeds to step S11, the recording operation is started. When step S10 or S11 is executed, the process returns to step S2. In this way, each time the video trigger button 34 is pressed, the recording operation is started and stopped repeatedly, and the operation state is always displayed on the display section of the electronic viewfinder 18.

In this way, at the time of video shooting, the focusing lens is driven so as to eliminate the detected defocus amount, so that stable focus adjustment control can be performed. Further, since the lens driving speed at this time is set low, the driving sound can be reduced. Further, if such control is performed, a slight tracking delay occurs, but since the depth of field of the video shooting system is deep, it does not pose a problem for general subjects.

Next, while the steps S2 to 11 are being executed, when the release switch SW2 is turned on by pressing the release button 35, the interrupt function immediately shifts to step S12 to start the release operation. In step S13, the flag LSP is set to H to set the lens drive speed to high speed. Then, in the subsequent step S14, the tracking delay amount generated during the release time lag and the AF time lag due to the movement of the subject is calculated from the past focus adjustment data by "prediction calculation 1". This calculation method will be described later. Step S1
In step 5, the focusing lens is driven so as to eliminate the tracking delay amount calculated in step S14. This makes it possible to take pictures that are in focus. At this time, since the flag LSP is set to H in step S13, the lens is driven at high speed and the time required for driving is short.

In step S16, the sub-mirror 14 is driven by the motor to retract the sub-mirror 14 and the light shielding member 16 out of the photographing optical path. In step S17, the stepping motor drives the aperture 4 to the aperture value obtained in step S3. Whether or not the sub-mirror retracting and diaphragm control in steps S16 and 17 have been completed is determined in step S1.
If it is detected in step 8 that any one of them is not completed, the process stands by in step S18, and if it is confirmed that the control of both is completed, the process proceeds to step S19. In step S19, step S1
It is determined whether or not the lens driving started in step 5 is completed,
If the lens is being driven, the process stands by in step S19, and if it is detected that the lens has been driven, the process proceeds to step S20. In step S20, the shutter is controlled by the shutter control value calculated in step S3 to expose the silver salt film 5.

When the control of the shutter is completed, the stepping motor is controlled so as to open the diaphragm 4 in the next step S21, and subsequently, the returning operation of the sub mirror 14 and the light shielding member 16 is performed in step S22. Next step S
At 23, as in step S18, the completion of the return of the sub-mirror 14 and the opening of the diaphragm is waited, and when the control of both is completed, the process proceeds to step S24. Step S24
Then, the flag LSP is set to L, the driving speed of the lens is set to a low speed, and in the next step S25, the motor is properly controlled to wind up one frame of film. The above is the operation sequence of the entire camera of the first embodiment.

FIG. 3 is a flow chart of the "prediction calculation 1" subroutine of step S14 of FIG. 2, in which the lens drive amount DL for correcting the tracking delay caused by the AF time lag and the release time lag is calculated. When this subroutine is called, through step S101,
In step S102, a time lag TL of tracking delay is calculated. This is executed by obtaining the sum of the time (AF time lag) TM2 required for the previous focus adjustment and the release time lag TR.

In step S103, the coefficient A of the quadratic term of the prediction equation using the quadratic function is calculated, and in step S104, the coefficient B of the primary term is calculated. Here, DF1 is the defocus amount at the time of the focus detection two times before, DF2 is the defocus amount at the time of the previous focus detection, DF3 is the defocus amount detected this time, DL1 is the lens drive amount at the time before two, DL
2 is the previous lens drive amount. In step S105, the lens drive amount DL for correcting the tracking delay is calculated by the prediction calculation using the quadratic function, and the step S105 is performed.
This subroutine is returned at 106. Here, the method of this "prediction calculation 1" has been disclosed by the present applicant, and thus detailed description thereof will be omitted.

As described above, in the first embodiment, during video recording, very high focus accuracy is not required, so the lens drive is performed so as to eliminate the defocus amount detected for stable focus adjustment. I do. At this time, driving noise can be reduced by driving the lens at a low speed. When still shooting is performed during video shooting, high-precision lens adjustment is performed in still shooting that requires high focus accuracy by driving the lens at high speed so as to eliminate tracking delay during the release time lag. Since it can be performed and the lens driving is completed in a short time, it is not necessary to lengthen the release time lag, and therefore, there is no problem of missing a photo opportunity. Here, if the lens is driven at high speed, the driving noise also increases, but the driving time is short, and the driving noise of the sub-mirror 14 and the driving noise of the diaphragm, which is the release preparation operation, overlap with each other, so that there is no problem.

FIG. 4 is a flow chart for explaining the operation of the entire camera according to the second embodiment of the present invention. Since the mechanism and circuit constituting the camera are the same as those in the first embodiment, the description thereof is omitted here. To do. The control of the second embodiment is the first
The point different from the above embodiment is that predictive control is also performed for focus adjustment at the time of video shooting in order to deal with a fast-moving subject whose tracking delay becomes a problem at the time of video shooting.

When the power of the camera is turned on, the process proceeds to step S202 via step S201. Step S
In 202, the state of the video standby switch (not shown) is detected, and when the video recording standby operation is performed, the process proceeds to step S203, and otherwise, the process stays in step S202 and the state detection of the video standby switch is repeated. . In step S203, the output signal of the solid-state image sensor 13 and the video aperture unit 11
The subject brightness is calculated from the aperture value and the shutter speed and the aperture value for proper exposure are calculated from the subject brightness and the sensitivity of the loaded film, and stored in a predetermined area of the RAM. The switch SW2 that is turned on by pressing the release button is turned on, and the shutter and the diaphragm are controlled based on these values when the film exposure operation is performed.

In the next step S204, the focus detection device 1
The line sensor 5 is controlled to convert a pair of subject images formed by the light fluxes transmitted through different regions of the lens unit 2 into an electric signal, and the electric signal is A / D converted and stored in the memory. In step S205, step S
A shift amount (phase difference) between the relative positions of the two images is calculated from the image signal captured by 204, and the defocus amount of the lens unit 2 is calculated from this phase difference. The method of calculating the phase difference and the defocus amount is a known technique, and the description thereof is omitted here.

Step S206 is a "prediction calculation 2" subroutine, in which the tracking delay amount caused by the AF time lag and the release time lag is calculated based on the current focus detection result and the past focus adjustment data, and the AF time lag for video shooting is calculated. The lens drive amount that takes into account the following delay and the lens drive amount that corrects the following delay corresponding to the release time lag for still photography are calculated. The detailed description will be given later.

In step S207, the flag LSP for setting the lens driving speed is set to L and the driving speed is set to a low speed. In step S208, the focus lens is driven by the lens drive amount in consideration of the tracking delay for the AF time lag calculated in step S206 to perform focus adjustment. As a result, even if the subject is moving fast, it is possible to shoot video without delay in tracking. Step S20
At 9, the state of the trigger button 34 for starting and stopping video recording is detected. If the trigger button 34 is in the on state, the process proceeds to step S210, and if not, the process returns to step S202. In step S210, it is determined whether or not a video recording operation is being performed,
If the recording operation is being performed, the process proceeds to step S211, the recording operation is stopped, and if the recording operation is not being performed, the process proceeds to step S212 to start the recording operation. When step S211 or S212 is executed, the process returns to step S202.

In steps S202 to S212, when the release button is pressed and the release switch SW2 is turned on while the control for video shooting is being performed, the interrupt function immediately causes step S2.
The process moves to 13 to start the release operation. When the release operation is started, it goes through step S213 and then step S
At 214, a flag LSP for setting the lens driving speed is set to H, and the lens is driven at a high speed. In the next step S215, lens driving is performed to correct the tracking delay for the release time lag calculated in step S206. At this time, the flag LSP is set to H in step S214.
Since it is set to, the lens is driven at high speed, and the lens drive time is shortened.

In step S216, the sub mirror 14 and the light blocking member 16 of the camera are retracted out of the photographing optical path. This is executed by controlling a motor (not shown). Then, in the next step S217, the diaphragm is driven by a stepping motor (not shown) up to the diaphragm control value calculated in step S203. Whether or not the sub-mirror retraction and aperture control in steps S216 and 217 have been completed is determined in step S21.
8 and if any of them is not completed, the process waits at step S218 and the state is continuously detected. When both control ends are confirmed, the process proceeds to step S219. In step S219, the state is detected whether or not the lens driving executed in step S215 is completed. If the lens is still being driven, the state is waited in step S219 and the state is continuously detected.

When it is confirmed that the lens driving is completed, the process proceeds to step S220, the shutter is controlled by the shutter control value calculated in step S203, and the film is exposed. When the control of the shutter is completed, the stepping motor is driven so as to open the diaphragm in the next step S221, and subsequently, the returning operation of the sub mirror 14 and the light shielding member 16 is performed in step S222. Sub mirror 1
The return operation of 4 and the light shielding member 16 is controlled by being driven by a motor (not shown). In the next step S223, similarly to step S218, the control for returning the sub-mirror 14 and the opening of the diaphragm are completed, and when both control are completed, the process proceeds to step S224. In step S224, the flag LSP is set to L, and the lens driving speed is set to low speed. Then, in step S225, one frame of film is wound by properly controlling the motor. The above is the operation sequence of the entire camera of the second embodiment.

FIG. 5 is a flow chart of the "prediction calculation 2" subroutine of step S206 of FIG. In this subroutine, in order to prevent the tracking delay during video shooting, the lens drive amount that takes into account the tracking delay for the AF time lag and the release time lag amount to prevent the tracking delay during still shooting during video shooting. The lens drive amount for correcting the following delay of is calculated. When this subroutine is called, it goes through step S301 and then step S30.
In 2, the defocus data is updated. DF1 here
The defocus amount at the time of the focus detection two times before is stored in DF2, the defocus amount of the previous focus detection in DF2, and the defocus amount obtained in the focus detection operation this time is stored in DF3. In the subsequent step S303, the lens drive amount data is updated, the lens drive amount of the previous two times is stored in DL1, and the previous lens drive amount is stored in DL2.

In step S304, the time lag TLM used for the prediction calculation during video shooting is calculated. Here, the time required for the previous focus adjustment (AF time lag) T
Input M2 to TLM. In step S305, the time lag TLS used for the prediction calculation at the time of still shooting is calculated. Here, the sum of the AF time lag TM2 and the release time lag RT is input to TLS. In step S306, the coefficient A of the quadratic term of the prediction formula using the quadratic function is calculated. In step S307, the coefficient B of the first-order term is calculated. The method of these calculations has already been disclosed by the present applicant, and thus detailed description thereof will be omitted.

In a succeeding step S308, a lens driving amount DLM for driving the lens in step S208 for performing focus adjustment during video shooting is calculated by a predictive calculation using a quadratic function. Here, the lens drive amount is calculated in consideration of the tracking delay corresponding to the AF time lag. In the next step S309, the prediction operation using the quadratic function
Step S of lens drive for focus adjustment during still photography
The lens drive amount DLS of 215 is calculated. Here, the lens drive amount for correcting the tracking delay corresponding to the release time lag is calculated. Then, in step S310, this subroutine is returned.

As described above, in the second embodiment, the tracking delay corresponding to the AF time lag is corrected during video recording, so that focus adjustment without tracking delay can be performed even on a fast-moving subject. The lens drive can be performed at a high speed during still shooting, and the lens drive can be completed without increasing the release time lag by performing the lens drive for correcting the tracking delay corresponding to the release time lag at high speed. As a result, it is possible to perform still photography in focus without missing a photo opportunity.

FIG. 6 is a flow chart showing the operation of the entire camera according to the third embodiment. Focusing when the defocus amount (focusing width) that can be regarded as the in-focus state is different between video shooting and still shooting. The adjustment operation will be described. Here, since the mechanism and the circuit constituting the camera are the same as those in the first embodiment, the description thereof will be omitted. When the power switch of the camera is turned on, the process goes to step S401 through step S401.
Go to 02. In step S402, when the state of the video standby switch is detected and the standby operation for video recording is performed, if the process does not proceed to step S403, the process remains in step S402 and the state detection of the video standby switch is repeated.

In step S403, the subject brightness is calculated from the output signal of the solid-state image pickup device 13 and the aperture value of the video aperture unit, and the shutter speed for performing an appropriate exposure is calculated from the subject brightness and the sensitivity of the loaded film. The time and aperture value are calculated and stored in a predetermined area of the RAM. Then, the switch SW2 that is turned on by pressing the release button is turned on, and when performing the exposure operation of the film, the shunter and the diaphragm are controlled based on this value.

In the next step S404, the line sensor of the focus detection device is controlled to convert a pair of subject images formed by the light flux transmitted through different regions of the lens unit into an electric signal, and this electric signal is / D convert and store in memory. In step S405, step S40
The phase difference between the two images is calculated from the image signal captured in 4, and the defocus amount of the lens unit 2 is calculated from this phase difference. In step S406, the flag LSP for setting the drive speed of the focusing lens is set to L, and the lens drive speed is set to a low speed.

In step S407, the focus width (3 · F · δ) during video shooting is compared with the absolute value of the defocus amount DEF detected in step S405, and | DEF |> 3
If F · δ, it means that the focus lens is out of focus, and it is necessary to adjust the focus. If the focus lens is not driven so as to eliminate the defocus amount detected in step S408, the focus lens is focused. Since this is the state and there is no need for focus adjustment, the process moves to step S409. This step S
The lens drive of 408 is the flag LSP in step S406.
Since L is set to L, low speed driving is performed and driving noise can be reduced.

In step S409, the state of the trigger button 34 for starting and stopping the video recording is detected. If the video trigger button 34 is in the on state, the process proceeds to step S410, and if not, the step S402.
Return to. In step S410, it is determined whether or not a video recording operation is being performed. If the recording operation is being executed, the process proceeds to step S411, and the recording operation is stopped. If the recording operation is not being performed, the process proceeds to step S412 and the recording operation is started. To do. Then, in step S411 or S4
When step 12 is executed, the process returns to step S402.

Next, when the release button is pressed while the control for video shooting is being performed in steps S402 to S412 and the release switch SW2 is turned on, the interrupt function immediately shifts to step S413. Release operation starts. When the release operation is started, it is compared whether or not the absolute value of the defocus amount DEF detected in step S414 through step S413 is larger than the focusing width 3 · F · δ during video shooting.
If DEF |> 3 · F · δ, the focus is adjusted in step S408, so it is determined that it is in focus, and the process proceeds to step S418, and if not | DEF |> 3 · F · δ, Proceed to S415.

In step S415, the in-focus width F.delta. At the time of still photography is compared with the defocus amount DEF. | DEF |>
If it is F · δ, it means that the object is out of focus, and it is necessary to perform focus adjustment. Therefore, the process proceeds to step S416, and otherwise, the process proceeds to step S418. Where F is the F of the taking lens
The number, δ, is the permissible circle of confusion diameter. The focus width at the time of video shooting is larger than the focus width at the time of still shooting, and in this embodiment, the value is 3F · δ, which is three times F · δ. In step S416, the flag LSP is set to H, and the lens driving speed is set to high speed. Then, in step S417, the lens is driven at high speed so as to eliminate the defocus amount DEF.
In step S418, the sub-mirror 14 and the light blocking member 16 of the camera are retracted to the outside of the photographing optical path. Then, in the next step S419, the diaphragm is driven to the diaphragm control value calculated in step S403.

It is detected in step S420 whether or not the sub mirror retracting and aperture control in steps S418 and S419 are completed. If any of them is not completed, this step S4
It waits at 420 and continues to detect the state. When both control ends are confirmed, the process proceeds to step S421. In step S421, it is detected whether or not the lens driving executed in step S417 is completed. If the lens driving is still in progress, the process waits in step S421, and when it is confirmed that the lens driving is completed, the process proceeds to step S422. In step S422, the shutter control is performed based on the shutter control value calculated in step S403, and the film is exposed. When the shutter control ends, the next step S42
In step 3, the stepping motor is driven so as to open the diaphragm, and subsequently in step S424, the returning operation of the sub mirror 14 and the light shielding member 16 is performed.

In the next step S425, step S42
As in the case of 0, the control waits for the control of the return of the sub-mirror 14 and the opening of the diaphragm to be completed. In step S426, the flag LS
Set P to L and set the lens drive speed to a low speed.
Then, in step S427, one frame of film is wound by properly controlling the motor.

According to the third embodiment, the focusing width at the time of video shooting, which does not require high focus accuracy, is larger than the focusing width at the time of still shooting, and can be regarded as the in-focus state at the time of video shooting. Even if it is possible, the subject may not be considered to be in focus during still shooting. In such a case, by focusing the lens by driving the lens at high speed during the release time lag, it is possible to perform still photography in focus without increasing the release time lag.

[0057]

As described above, according to the present invention, the focus adjustment control in the case of video shooting alone and the focus adjustment control in the case of still shooting are different, and when still shooting is performed during video shooting. Since the focus adjustment suitable for still shooting is performed during the release time lag, the release time lag does not become long, and still shooting with good focus accuracy can be performed.

By driving the lens at a low speed during video shooting and driving the lens at a high speed during the release time lag during still shooting, the release time lag does not become longer and the drive time can be shortened. Therefore, there is an effect that the shutter chance is not missed and the lens driving sound is reduced. Further, since the tracking delay caused by the movement of the subject can be corrected during the release time lag, it is possible to perform the exposure in the focused state.

[Brief description of drawings]

FIG. 1 is a block diagram conceptually showing the present invention.

FIG. 2 is a flowchart showing the overall operation of the compound camera according to the first embodiment of the present invention.

FIG. 3 is a flowchart of a prediction calculation 1 subroutine of FIG.

FIG. 4 is a flowchart showing the overall operation of the compound camera according to the second embodiment of the present invention.

5 is a flowchart of a prediction calculation 2 subroutine of FIG.

FIG. 6 is a flowchart showing the overall operation of the compound camera according to the third embodiment of the present invention.

FIG. 7 is a side sectional view showing an embodiment of a compound camera.

FIG. 8 is a top view showing an embodiment of a compound camera.

FIG. 9 is a block diagram showing an electric circuit of the compound camera.

[Explanation of symbols]

 50 compound camera 51 still camera unit 52 video camera unit 53 shooting lens 54 focus detection unit 55 lens drive unit 56 control unit

Claims (7)

[Claims] 1. A composite camera having a still camera section for performing still picture shooting, a video camera section for video shooting, and a taking lens including a focus lens, which is commonly used by the still camera section and the video camera section, A focus detection unit that detects a focus state of the focus lens to obtain a defocus amount, a lens drive unit that drives the focus lens, and a focus state based on the defocus amount obtained by the focus detection unit. Obtain the lens drive amount that can be obtained,
A control means for controlling the lens drive means in accordance with the lens drive amount, wherein the control means is configured to perform different focus adjustment control at the time of the still shooting and at the time of video shooting alone. A compound camera characterized by performing focus control for still shooting during a release time lag when still shooting is performed during video shooting. 2. The control means drives the lens at a first speed during the video shooting alone, and drives the lens at a second speed which is higher than the first speed during the release time lag. The control is performed as follows.
The compound camera described. 3. The compound camera according to claim 1, wherein the lens drive during the release time lag is a correction drive for correcting a tracking delay caused by the movement of the subject. 4. The compound camera according to claim 3, wherein the correction amount for the correction driving is a defocus amount corresponding to a tracking delay amount caused by a release time lag. 5. The compound camera according to claim 4, wherein the correction amount is a defocus amount corresponding to a tracking delay amount caused by an AF time lag and a release time lag. 6. The lens driving is performed during the release time lag when the focusing width in the video shooting alone and the focusing width in the still shooting are different and the defocus amount is larger than the focusing width in the still shooting. The compound camera according to claim 1, wherein: 7. The compound camera according to claim 1, wherein a lens driving amount for driving the lens during the release time lag is an amount corresponding to the detected defocus amount.