JP3937553B2 - camera - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electronic camera using a mechanical shutter that is limited at the time of full opening for strobe tuning, such as a blade-type focal plane shutter.
[0002]
[Prior art]
Conventionally, in an electronic camera that captures an image using a solid-state imaging device such as a CCD that converts light from a photographing lens into an electrical signal, an electronic device that controls the imaging time by controlling an imaging operation time for capturing light that forms an image Some have a shutter function and a mechanical shutter to reduce smear and the like due to excess light after the image pickup device takes in a necessary amount of light.
[0003]
As this type of camera, there are many single-lens reflex electronic cameras pursuing high image quality, and a focal plane shutter is used as a mechanical shutter to control imaging time and aperture separately. Often.
[0004]
[Problems to be solved by the invention]
However, if an electronic camera using a focal plane shutter is used to take a strobe image, the strobe is only taken when the focal plane shutter opens the full screen to the solid-state image sensor, that is, when the focal plane shutter is fully open. It becomes possible to emit light, and the time for synchronizing with the flash becomes longer than a certain time. This is because when the strobe is emitted in a time shorter than a certain time, a part of light is blocked by the blade member of the focal plane shutter, and so-called uneven exposure occurs.
[0005]
For this reason, for example, in a scene where you want to capture strobe images under bright external light due to backlight, etc., if you want to capture external light properly at the time of flash synchronization, you must reduce the aperture If it is reduced, the range of the strobe light is extremely shortened, and the distance to the subject that can be imaged is limited. There are also cases where the aperture is still not sufficient in combination with the flash synchronization time even with the minimum aperture.
[0006]
Furthermore, when you want to blur the background by opening the aperture for shooting purposes, as described above, the exposure will be overexposed to the outside light at the time of flash synchronization, which makes it impossible to perform normal flash photography. Is possible.
[0007]
Conventionally, in order to perform strobe shooting under such conditions, so-called FP light emission has been proposed in which the strobe continues to shine during imaging so that exposure unevenness due to the shutter does not occur even when the shutter is not fully open. However, this FP light emission has a drawback that the amount of light emission becomes extremely small and the reach distance of the strobe light becomes very short because the strobe light must continue to emit light intermittently during imaging.
[0008]
Accordingly, an object of the present invention is to provide an electronic camera that can perform strobe photography without reducing the amount of light emission at all shutter seconds even when a focal plane shutter is used.
[0009]
Furthermore, the present invention uses a strobe at full light even if the photographer dislikes smear and other image performance degradation due to the control of the imaging time using an electronic shutter, and even if the smear or other image performance degradation is allowed. An object of the present invention is to provide an electronic camera that can meet the demands of a photographer who wants.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, in the first invention of the present application, an imaging means, an electronic shutter means for controlling an imaging operation time of the imaging means, and a mechanical shutter means for controlling a light incident time to the imaging means are provided. In the electronic camera having a stroboscopic image, if the target imaging time by the imaging means is longer than the fully open second of the mechanical shutter means, the imaging time of the imaging means is controlled by the light incident time control by the mechanical shutter means, and the imaging means When the target imaging time is shorter than the fully open time of the mechanical shutter means, the mechanical shutter means is operated more than the fully open time, and the control means for controlling the imaging time of the imaging means by controlling the imaging operation time of the electronic shutter means is provided. .
[0011]
As a result, it is possible to realize an electronic camera that can be stroboscopically tuned at all imaging times (shutter seconds).
[0012]
In the above invention, at the time of non-strobe imaging, the imaging time control of the imaging means may be performed by the light incident time control by the mechanical shutter means.
[0013]
Further, in the second invention of the present application, there is provided an imaging means, an electronic shutter means for controlling an imaging operation time of the imaging means, and a mechanical shutter means for controlling a light incident time to the imaging means. In an electronic camera capable of selectively setting a first mode (normal strobe mode) in which strobe imaging is performed by operating at full open time or more and a second mode (full speed tuning mode) in which strobe imaging is performed for the entire imaging time. When the first imaging mode is set when the target imaging time is shorter than the fully open second time of the mechanical shutter means, the imaging time control of the imaging means is performed by the light incident time control by the fully open second time operation of the mechanical shutter means, When the second mode is set, the mechanical shutter means is operated for more than the fully open time and the electronic shutter means Is provided with a control means for performing imaging time control of the imaging unit by an image operation time control.
[0014]
As a result, it is possible to realize a camera that can fully exhibit the ability of the strobe in each mode and can cope with image degradation such as smear.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
FIG. 1 shows an electronic camera which is a first embodiment of the present invention. In this figure, reference numeral 1 denotes an electronic camera, and reference numeral 2 denotes a lens device that forms an image of a subject on an imaging surface. Reference numeral 3 denotes a mirror device that reflects and guides the subject image formed by the lens device 2 to the focus plate 7 during finder observation, and retracts from the optical path of the subject luminous flux during photographing.
[0016]
Reference numeral 4 denotes a mechanical shutter device that mechanically controls the incident time of the subject light flux on the imaging surface. The mechanical shutter device 4 blocks the subject luminous flux during finder observation, and retracts from the optical path of the subject luminous flux during the finder observation, and the leading blade group 4a that evacuates from the subject high-speed optical path according to the release signal during imaging and starts exposure. In addition, the focal plane shutter has a rear blade group 4b that shields a subject light beam at a predetermined timing after the start of traveling of the front blade group 4a during imaging.
[0017]
Reference numeral 5 denotes a solid-state image pickup device such as a CCD that picks up a subject image formed by the lens device 2 and converts it into an electrical signal. It has a controlled electronic shutter function.
[0018]
Reference numeral 6 denotes an electric substrate that is electrically and mechanically coupled to the solid-state imaging device 5 and holds them. Reference numeral 7 denotes a focus plate on which an image formed by the lens device 2 and reflected by the mirror device 3 is formed. A finder image is formed on the focus plate 7 during finder observation.
[0019]
Reference numeral 8 denotes a penta roof mirror or a penta prism device that converts and reflects an object image formed on the focusing plate 7 into an erect image. Reference numeral 9 denotes an eyepiece device that causes the subject image reflected by the penta roof mirror or the penta prism device 8 to reach the eyes of the photographer.
[0020]
Next, the operation of the electronic camera configured as described above will be described with reference to the flowchart of FIG.
[0021]
When a power switch (not shown) is turned on in step S1, the electronic camera 1 enters a standby state for photographing. Then, when SW1 (not shown) which is turned on by half-pressing the release button in step S2 is turned on, photometry is started in step S3.
[0022]
Next, the aperture value (Av value) and imaging time (Tv value) corresponding to each mode are determined by the exposure mode selected by a mode selection switch (not shown) (steps S4 to S10).
[0023]
Here, if the exposure mode is the Av priority mode (step S4), the Av value is an arbitrary value selected by the photographer, and the Tv value is determined in accordance with the photometric value measured in step S3 (step S8).
[0024]
If the exposure mode is the Tv priority mode (step S5), the Tv value becomes an arbitrary value selected by the photographer, and the Av value is determined in accordance with the photometric value measured in step S3 (step S9).
[0025]
If the exposure mode is the program mode (step S6), the Av value and the Tv value are determined from the program diagram (not shown) according to the photometric value measured in step S3 (step S10). Although various patterns can be considered as the program diagram, the same flow is basically passed regardless of whether one pattern or a plurality of patterns are provided.
[0026]
When the exposure mode is manual exposure, both the Tv value and the Av value are arbitrary values selected by the user (step S7).
[0027]
As described above, regardless of which mode is selected, the Tv value (target imaging time) and Av value to be controlled up to step S10 are determined.
[0028]
Next, in step S11, when SW2 (not shown) that is turned on by fully pressing the release switch is turned on, it is determined whether or not flash photography is performed in step S12. When it is not strobe shooting, the process proceeds to step S18, and the control of the imaging time of the subject image by the solid-state imaging device 5 is performed by the incident time control of the subject luminous flux to the solid-state imaging device 5 by the mechanical shutter device 4.
[0029]
That is, the front blade group 4a of the shutter device 4 is moved to the aperture opening side to start imaging (steps S19 and S20), and the rear blade group 4b is moved to the aperture closing side to end the imaging (step S21). Thus, the subject luminous flux incident on the solid-state imaging device 5 during steps S18 to S21 is limited to only light necessary for imaging. Therefore, an extra luminous flux other than that required for imaging does not reach the solid-state imaging device 5, so that a signal with a good S / N is generated and an image having almost no smear is generated.
[0030]
On the other hand, if it is determined that the flash photography is performed in step S12, the magnitude of the Tv value to be controlled is determined in step S13. As described above, the mechanical shutter device 4 of the present embodiment covers the aperture during viewfinder observation, and the leading blade group 4a that travels in the direction to open the aperture during shooting, and retracts from the aperture during viewfinder observation, and takes a picture. Sometimes the front blade group 4a and the rear blade group 4b form slits when the imaging time is short because the rear blade group 4b travels in a direction covering the aperture at a predetermined timing after the front blade group 4a travels. I will run. For this reason, when the strobe is caused to emit light in such a shutter running state, since the light emission time of the strobe light is very short, the solid-state imaging device 5 exposes only a part of the screen with the strobe light, and thus exposure. An uneven screen is generated.
[0031]
Therefore, when the leading blade group 4a is completely retracted from the aperture and the trailing blade group 4b does not block the aperture, that is, when the imaging time is equal to or longer than the fully open second of the shutter device 4 (the aperture is not blocked). ), It is possible to perform proper flash photography with the shutter device 4.
[0032]
Therefore, in step S13, it is determined whether or not the Tv value to be controlled is shorter than when the mechanical shutter device 4 is fully open. When the Tv value is longer than the fully open time, if the flash is emitted in synchronism with the full opening of the mechanical shutter device 4, proper flash photography is possible. Therefore, the actual imaging time is set to the mechanical shutter with the Tv value as a target. Control is performed by the apparatus 4, and the sequence of steps S18 to S21 is performed.
[0033]
On the other hand, when the Tv value to be controlled is shorter than the time when the mechanical shutter device 4 is fully opened, the strobe light is blocked if the actual imaging time control is performed with the mechanical shutter device 4 as described above. Proceed to S14.
[0034]
In step S14, in order that the mechanical shutter device 4 does not block the strobe light, the shutter device 4 is controlled at a time equal to or longer than the fully open time, and in step S15, the leading blade group 4a of the shutter device 4 is moved to the aperture opening side. In step S16, the actual imaging time with the Tv value as a target is controlled by the electronic shutter function of the solid-state imaging device 5. When the imaging is thus completed, the process proceeds to step S17, and the rear blade 4b of the shutter device 4 is caused to travel in the closing direction.
[0035]
By performing the imaging control when the Tv value to be controlled in this way is shorter than the fully open time of the mechanical shutter device 4, the strobe light is not blocked by the mechanical shutter device 4, and the Tv value is targeted. The imaging time is also protected.
[0036]
Thus, in this embodiment, since the shutter (mechanical shutter device 4 and electronic shutter function) for controlling the imaging time by the solid-state imaging device 5 is switched according to the Tv value at the time of flash photography, all imaging is performed. An electronic camera capable of strobe tuning with respect to time (Tv value) can be realized.
[0037]
When imaging is completed in step S17 or step S21, the image signal stored in the solid-state imaging device 5 is read (step S22), image processed (step S23), and stored in a memory device (not shown) (step S24). One imaging is finished (step S25).
[0038]
(Second Embodiment)
FIG. 3 shows an operation flowchart of the electronic camera according to the second embodiment of the present invention. The configuration of the electronic camera of the present embodiment is almost the same as the configuration of the electronic camera of the first embodiment, and therefore common components will be described using the same reference numerals as those of the first embodiment.
[0039]
When a power switch (not shown) is turned on in step S101, the electronic camera 1 enters a standby state for photographing. Next, the user can select the strobe mode in step S102. The strobe modes that can be selected include a normal strobe mode in which the mechanical shutter device 4 is controlled at a time equal to or longer than the fully open time, and a full-speed synchronization mode that enables strobe photography at all times. When the user does not select the strobe mode, the normal strobe mode is initially set.
[0040]
In step S103, when SW1 (not shown) that is turned on by half-pressing the release button is turned on, photometry is started in step S104.
[0041]
Next, the aperture value (Av value) and imaging time (Tv value) corresponding to each mode are determined by the exposure mode selected by a mode selection switch (not shown) (steps S105 to S111).
[0042]
If the exposure mode is the Av priority mode (step S105), the Av value is an arbitrary value selected by the photographer, and the Tv value is determined in accordance with the photometric value measured in step S104 (step S109).
[0043]
If the exposure mode is the Tv priority mode (step S106), the Tv value becomes an arbitrary value selected by the photographer, and the Av value is determined in accordance with the photometric value measured in step S104 (step S110).
[0044]
If the exposure mode is the program mode (step S107), the respective Av value and Tv value are determined from the program diagram (not shown) according to the photometric value measured in step S104 (step S111). Although various patterns can be considered as the program diagram, the same flow is basically passed regardless of whether one pattern or a plurality of patterns are provided.
[0045]
When the exposure mode is manual exposure, both the Tv value and the Av value are arbitrary values selected by the user (step S108).
[0046]
As described above, regardless of which mode is selected, the Tv value (target imaging time) and Av value to be controlled up to step S111 are determined.
[0047]
Next, in step S112, when SW2 (not shown) which is turned on by fully pressing the release switch is turned on, it is determined whether or not the flash photography is performed in step S113. If it is not strobe shooting, the process proceeds to step S124, and the imaging time of the subject image by the solid-state imaging device 5 is controlled by the incident time control of the subject luminous flux to the solid-state imaging device 5 by the mechanical shutter device 4.
[0048]
That is, the leading blade group 4a of the shutter device 4 is moved to the aperture opening side to start imaging (steps S125 and S126), and the predetermined trailing blade group 4b is moved to the aperture closing side to end imaging (step S127). ). Thus, the subject luminous flux incident on the solid-state imaging device 5 during steps S125 to S127 is limited to only light necessary for imaging. Therefore, an extra luminous flux other than that required for imaging does not reach the solid-state imaging device 5, so that a signal with a good S / N is generated and an image having almost no smear is generated.
[0049]
On the other hand, if it is determined that the flash photography is performed in step S113, the magnitude of the Tv value to be controlled is determined in step S114. As described above, the mechanical shutter device 4 of the present embodiment covers the aperture during viewfinder observation, and the leading blade group 4a that travels in the direction to open the aperture during shooting, and retracts from the aperture during viewfinder observation, and takes a picture. Sometimes the front blade group 4a and the rear blade group 4b form slits when the imaging time is short because the rear blade group 4b travels in a direction covering the aperture at a predetermined timing after the front blade group 4a travels. I will run. For this reason, when the strobe is caused to emit light in such a shutter running state, since the light emission time of the strobe light is very short, the solid-state imaging device 5 exposes only a part of the screen with the strobe light, and thus exposure. An uneven screen is generated.
[0050]
Therefore, when the leading blade group 4a is completely retracted from the aperture and the trailing blade group 4b does not block the aperture, that is, when the imaging time is equal to or longer than the fully open second of the shutter device 4 (the aperture is not blocked). ), It is possible to perform proper flash photography with the shutter device 4.
[0051]
Therefore, in step S114, it is determined whether or not the Tv value to be controlled is shorter than when the mechanical shutter device 4 is fully open. When the Tv value is longer than the fully open time, if the flash is emitted in synchronism with the full opening of the mechanical shutter device 4, proper flash photography is possible. Therefore, the actual imaging time is set to the mechanical shutter with the Tv value as a target. Control is performed by the apparatus 4, and the sequence of steps S124 to S127 is performed.
[0052]
On the other hand, when the Tv value to be controlled is shorter than the fully open time of the mechanical shutter device 4, the process proceeds to step S115, and it is determined whether the strobe mode set in step S102 is the full-speed tuning mode or the normal strobe mode.
[0053]
Here, in the normal strobe mode, the control time of the mechanical shutter device 4 is set to be larger than the Tv value determined in steps S108, S109, S110, and S111, and the mechanical shutter device 4 is controlled at the fully open time ( Step S120). In step S121, the strobe light is emitted when the leading blade group 4a of the mechanical shutter device 4 opens the aperture and is fully opened. In this case, the solid-state imaging device 5 is exposed from when the leading blade group 4a starts to open (step S121) until the trailing blade group 4b covers the aperture (step S123). That is, at the time of shooting in the normal strobe mode according to the sequence of steps S120 to S123, the portion exposed with the external light component is so-called overexposed, which is the same as that of the conventional silver salt camera.
[0054]
If it is determined in step S115 that the strobe mode is the full-speed tuning mode, the process proceeds to step S116, and the mechanical shutter device 4 does not block the strobe light. We will control it. Then, in step S117, the leading blade group 4a of the shutter device 4 is caused to travel toward the aperture opening side, and in step S118, the actual imaging time with the Tv value as a target is controlled by the electronic shutter function of the solid-state imaging device 5. When the imaging is thus completed, the process proceeds to step S119, and the rear blade 4b of the shutter device 4 is caused to travel in the closing direction.
[0055]
That is, the imaging time in the full-speed tuning mode is all controlled by the electronic shutter function of the solid-state imaging device 5 regardless of the movement of the mechanical shutter device 4.
[0056]
As described above, according to the electronic camera of this embodiment, when the photographer selects the full-speed synchronization mode, it is possible to perform flash photography at all target imaging times. Furthermore, it is possible to select the normal strobe mode and obtain an image with a good S / N.
[0057]
When imaging is completed in step S119, step S123, or step S127, the image signal stored in the solid-state imaging device 5 is read (step S128), image-processed (step S129), and stored in a memory device (not shown) ( (Step S130) One imaging is finished (step S131).
[0058]
【The invention's effect】
As described above, according to the first invention of the present application, when the target imaging time by the imaging means is longer than the fully open second time of the mechanical shutter means in strobe shooting, the imaging time of the imaging means is controlled by the light incident time control by the mechanical shutter means. When the target imaging time by the imaging means is shorter than the fully open second time of the mechanical shutter means, the mechanical shutter means is operated for more than the fully open second time, and the imaging time control of the imaging means is performed by the imaging operation time control of the electronic shutter means As a result, an electronic camera that can be tuned to the strobe at any imaging time (shutter time) can be realized.
[0059]
In non-strobe shooting, smearing and the like can be reduced by controlling the imaging time of the imaging means by controlling the light incident time by the mechanical shutter means.
[0060]
Further, according to the second invention of the present application, when the target imaging time by the imaging unit is shorter than the time when the mechanical shutter unit is fully opened, when the first mode (normal strobe mode) is set, the mechanical shutter unit is fully opened. When the second mode (full speed tuning mode) is set, the mechanical shutter means is operated for more than the fully open second time and the electronic shutter means is imaged. Since the imaging time control of the imaging means is performed by time control, a camera that can fully demonstrate the ability of the strobe in each mode and can cope with image degradation such as smear is realized. be able to.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of an electronic camera according to a first embodiment of the present invention.
FIG. 2 is an operation flowchart of the electronic camera of the first embodiment.
FIG. 3 is an operation flowchart of the electronic camera according to the second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Electronic camera 2 Lens apparatus 3 Mirror apparatus 4 Mechanical shutter apparatus (focal plane shutter)
5 Solid-state imaging device 6 Electric substrate 7 Focus plate 8 Penta roof mirror or penta prism device 9 Eyepiece device

Claims (6)

In a camera having an imaging means, an electronic shutter means for controlling an imaging operation time of the imaging means, and a mechanical shutter means for controlling a light incident time on the imaging means,
When performing strobe imaging, if the target imaging time by the imaging means is longer than the fully open second of the mechanical shutter means, the imaging time of the imaging means is controlled by controlling the light incident time by the mechanical shutter means, and the imaging means Control means for operating the mechanical shutter means at least when the mechanical shutter means is fully open when the target imaging time is shorter than the fully open second and controlling the imaging time of the imaging means by controlling the imaging operation time of the electronic shutter means A camera characterized by comprising: The camera according to claim 1, wherein the control unit performs imaging time control of the imaging unit by light incident time control by the mechanical shutter unit during non-strobe imaging. An image pickup means, an electronic shutter means for controlling an image pickup operation time of the image pickup means, and a mechanical shutter means for controlling a light incident time to the image pickup means, and the mechanical shutter means is operated at a time of full open time or more. In a camera capable of selectively setting a first mode for performing strobe imaging and a second mode for performing strobe imaging for the entire imaging time,
When the target imaging time by the imaging means is shorter than the fully open time of the mechanical shutter means, and when the first mode is set, the imaging means is controlled by the light incident time control by the fully open time operation of the mechanical shutter means. Control to perform the imaging time control of the imaging means by operating the mechanical shutter means when the second mode is set, and operating the mechanical shutter means for more than the fully open time and imaging operation time control of the electronic shutter means A camera comprising means. The control means controls the imaging time of the imaging means by controlling the light incident time by the mechanical shutter means when the target imaging time by the imaging means is longer than the fully open second time of the mechanical shutter means when performing strobe imaging. The camera according to claim 3, wherein the camera is performed. 5. The camera according to claim 3, wherein the control unit performs imaging time control of the imaging unit by light incident time control by the mechanical shutter unit during non-strobe imaging. 6. 6. The camera according to claim 1, wherein the mechanical shutter means is a focal plane shutter.

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