JP2004151437A - Camera with built-in electronic flash - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera with a built-in electronic flash that can assist framing in darkness without any additional member. <P>SOLUTION: When a photometry result in photography is less than specified luminance as shown by steps S1, S4 (less than a reference value), S5, and S6 in figure, preliminary light emission is carried out and a normal photographing process is performed a specified time later, so when a subject viewed through a finder is too dark to confirm well, the arrangement of the subject in the finder can sufficiently be confirmed in the securedly specified time. A failure in photography such as defocusing and over(under)exposure due to unconfirmation of the subject arrangement in the finder can, therefore, be prevented. Further, opening of the pupil of the eye due to the preliminary light emission is made small, so what is called a red-eye phenomenon can be prevented. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a camera with a built-in strobe, and more particularly to a camera with a built-in strobe capable of assisting framing in darkness without additional members.
[0002]
[Prior art]
Some strobe devices (flash devices) in conventional cameras with a built-in strobe have a function of pre-flash (test flash) in addition to main flash. While the main flash is used for exposure during flash photography, the pre-flash uses a finder to determine the shadow state (illumination, reflection, direction and size of the subject's shadow, etc.) caused by the main flash. Through to check before shooting.
[0003]
The pre-emission is performed by causing the strobe device to emit light intermittently with a small amount of light. That is, the pre-emission is performed by intermittent light emission according to the pre-emission mode by directly controlling the light emission amount, light emission timing, and light emission period by using the strobe light emitting portion used as the auxiliary lighting for the main light emission.
As the pre-emission mode, for example, there are a portrait mode (frequency: 2 Hz, emission number: 3 times, emission time: 1 second) and a macro mode (frequency: 40 Hz, emission number: 160 times, emission time: 4 seconds).
[0004]
In recent years, some commercially available autofocus single-lens reflex cameras have an eye control function. According to this function, it is possible to select a distance measuring point by inputting a line of sight.
[0005]
That is, the user half-presses the shutter button while looking through the finder and looking at one of a plurality of focus areas provided in the finder field of view. Then, the line of sight of the user is detected by a line of sight detection CCD (Charge Coupled Device) area sensor, and a focus area at the detected line of sight is selected. Then, a focus state in the selected focus area is detected, and autofocus is performed by driving a lens based on the detection result.
[0006]
However, if an operation for instructing the activation of the auto focus (half-pressing the shutter button, eyepiece detection operation, etc.) is performed during the pre-flash, the subject not intended by the photographer (the in-focus state during the pre-flash) is set. An autofocus operation is performed so as to focus on a subject other than a certain main subject, and as a result, the focus state of the subject image may change.
[0007]
As such an autofocus operation, for example, a lens driving operation performed to focus on a subject (a background of a main subject or the like) at a largely out-of-focus position or a focus operation on a low-contrast subject is performed. Low contrast scan operation and the like.
When the focus state of the subject image changes in this way, a problem arises in that the work of checking the shadow state through the viewfinder is interrupted.
[0008]
In addition, during the pre-emission, the user tries to capture the entire subject while looking into the viewfinder, so that the user does not always capture the main subject accurately. Therefore, in the camera capable of selecting a distance measuring point by line-of-sight input, if the line-of-sight detection for instructing activation of auto-focus is performed during pre-flash, as described above, the camera focuses on a subject not intended by the photographer. The autofocus operation is performed so as to match. As a result, the focus state of the subject image may change.
Therefore, also in this case, there is a problem that the operation of checking the shadow state through the viewfinder is interrupted.
[0009]
The cause of interrupting the operation of checking the shadow state is not limited to a change in the focus state due to the autofocus operation. For example, the subject image confirmed through the finder is changed, such as when the focal length changes due to zooming or switching between two or more focal points, or when the finder field of view is changed during trimming or panoramic shooting. If the state changes during the pre-emission, the above-described check operation is interrupted.
[0010]
Also, if the camera has a function of performing zooming (auto-zoom function) so as to obtain an optimum shooting magnification based on a shooting distance obtained by auto-focusing, zooming is linked to auto-focusing. Therefore, the state of the subject image changes with the change in the angle of view accompanying the change in the focus state.
[0011]
In order to solve the above problem, even if an operation for instructing the setting of the subject image state is performed during the pre-emission, the operation of confirming the shadow state generated in the subject by the main emission through the finder before shooting is not interrupted. A camera system configured as described above has been proposed (see Patent Document 1).
[0012]
In this prior art invention, even if an autofocus operation for instructing the setting of the focus state is performed during the pre-flash, the microcomputer (control means) changes the focus state (confirmed by the finder) during the pre-flash. The autofocus operation of the focus drive unit is controlled so as not to change.
[0013]
[Patent Document 1]
JP-A-8-190136 (page 1)
[0014]
[Problems to be solved by the invention]
However, in the above-described prior art, a pre-emission irrelevant to a series of photographing operations to confirm a shadow of a subject and a pre-emission before main emission for preventing red-eye are performed, but a series of photographing operations are performed. In this case, a pre-flash is performed, and a series of photographing operations are not performed after the framing change time has elapsed.
[0015]
Here, framing refers to confirming the arrangement of a subject in a finder. If the framing change time can be secured, a failed photograph due to a framing shift can be eliminated.
[0016]
In addition, there is no pre-emission to assist framing when a strobe (strobe device) is not used (in a dark state or in a state close to a dark state). If this becomes possible, it is possible to eliminate failed photographs due to misalignment of framing.
[0017]
The present invention has been made in consideration of the above circumstances, and has as its object to provide a camera with a built-in strobe capable of performing framing assistance in darkness without additional members.
[0018]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, in a camera with a built-in strobe having both a pre-flash and a normal flash, if the photometry result at the time of shooting is less than a predetermined luminance, the pre-flash is performed. Then, after a lapse of a predetermined time, a normal photographing process is performed.
[0019]
In this way, for example, when the photometry result at the time of shooting is less than the predetermined luminance, as in step S1 → step S4 (less than the reference value) → step S5 → step S6 in FIG. Since the normal photographing process is performed after a lapse of a predetermined time, if the subject viewed through the viewfinder is dark and cannot be confirmed well, the arrangement of the subject on the viewfinder can be sufficiently confirmed during the secured predetermined time. .
[0020]
Therefore, unsuccessful photographs such as defocus and overexposure (under) due to unconfirmed object arrangement on the viewfinder can be prevented. In addition, since the pupil opening is reduced by the pre-emission, so-called red-eye can be prevented.
[0021]
Next, according to a second aspect of the present invention, in the camera with a built-in strobe according to the first aspect, even when the strobe is not used at the time of photographing, a pre-emission is performed.
[0022]
By doing so, for example, it is possible to not emit the strobe light through the processing of step S1 → step S4 (less than the reference value) → step S5 → step S6 in FIG. Even in this case, if the subject viewed through the viewfinder is dark and cannot be easily confirmed, the subject can be sufficiently confirmed on the viewfinder during the secured predetermined time.
[0023]
Therefore, unsuccessful photographs such as defocus and overexposure (under) due to unconfirmed object arrangement on the viewfinder can be prevented. Further, since the pupil opening is reduced by the pre-emission, red eyes can be prevented.
[0024]
Next, according to a third aspect of the present invention, in the camera with a built-in strobe according to the first aspect, the pre-flash light amount is changeable.
In this way, for example, as shown in FIG. 5, the light emission time and the number of times of the pre-emission can be changed to change the amount of the pre-emission, so that useless consumption of a battery (a secondary battery or the like) can be prevented.
[0025]
Next, according to a fourth aspect of the present invention, in the camera with a built-in flash according to the third aspect, the amount of the pre-emission light is changed according to the measured luminance.
In this way, for example, as shown in FIG. 5, the emission time of the pre-emission can be changed according to the luminance level (the measured luminance) based on the result of the rough emission, so that wasteful consumption of the battery can be prevented.
[0026]
Next, according to a fifth aspect of the present invention, in the camera with a built-in strobe according to the third aspect, the number of times of the pre-emission is changed according to the measured luminance.
[0027]
In this way, for example, as shown in FIG. 5, the number of times of the pre-light emission can be changed according to the luminance level based on the result of the rough light emission. The subject can be sufficiently confirmed by repeating the pre-emission several times. Therefore, there are no failed pictures.
[0028]
Next, according to a sixth aspect of the present invention, in the camera with a built-in strobe according to the third aspect, the light quantity of the pre-emission is stored in a light-emission amount storage means, and the light quantity of the pre-emission can be adjusted.
[0029]
In this way, the light amount of the pre-light emission is stored in the light emission amount storage means (EEPROM 30 in FIG. 1). Since the storage value (set value) of the light emission amount storage means can be changed, if the storage value is changed by a user or a clerk of a camera service store, for example, the user can take a picture as desired.
[0030]
Next, according to a seventh aspect of the present invention, in the camera with a built-in strobe according to the third aspect, a mode is provided in which a light amount of the pre-emission can be adjusted.
With this configuration, for example, an existing zoom button (zoomT, W button) is used as the adjustable mode, so that an increase in the cost of the camera can be suppressed and the amount of pre-emission light can be set with ease of use.
[0031]
Next, according to an eighth aspect of the present invention, in the camera with a built-in strobe according to the first aspect, the waiting time after the pre-emission can be changed.
In this way, the waiting time after the pre-emission can be changed according to the user's preference, so that framing that the user is satisfied with can be performed.
[0032]
Next, according to a ninth aspect of the present invention, in the camera with a built-in flash according to the eighth aspect, the waiting time after the pre-emission is stored in a waiting time storage means, and the waiting time after the pre-emission can be adjusted. There is.
[0033]
In this way, the stored value of the waiting time after the pre-emission in the waiting time storage means (for example, the EEPROM unit 30 in FIG. 1) can be changed, so that framing that the user is convinced can be performed.
[0034]
Next, according to a tenth aspect of the present invention, in the camera with a built-in strobe according to the eighth aspect, a mode is provided in which a waiting time after the pre-emission can be adjusted.
With this configuration, as an adjustable mode, for example, an existing zoom button (zoomT, W button) is used, so that an additional button is not required. Can be set.
[0035]
Next, according to an eleventh aspect of the present invention, in the camera with a built-in strobe according to the eighth aspect, during the waiting time after the pre-emission, the strobe power storage means is additionally charged.
With this configuration, the strobe power storage means (a capacitor (not shown)) is additionally charged during the waiting time after the pre-emission, so that a decrease in the emission amount during the main emission can be suppressed.
[0036]
Next, according to a twelfth aspect of the present invention, in the camera with a built-in strobe according to the eleventh aspect, when the framing assist function is effective, a charge level higher than a normal charge level is set.
With this configuration, when the framing assisting function is effective, the charging is performed at a higher charging level than usual, so that it is possible to suppress a decrease in the light emission amount during the main light emission.
[0037]
Next, according to a thirteenth aspect of the present invention, in the camera with a built-in flash according to the eleventh to twelfth aspects, if the switch for half-pressing the photographing button is turned off after using the framing assist function, the photographing is interrupted. Then, the strobe electric storage means is charged.
[0038]
By doing so, for example, the processing of step S1 → step S4: less than the reference value → step S5 → step S7: $ FF → step S17 → step S18 in FIG. 4 is performed. Charging becomes possible, and a sufficient amount of light for flash emission can be secured.
[0039]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described based on the illustrated embodiments. FIG. 1 is a block diagram of the present embodiment.
As shown in FIG. 1, the camera SN with a built-in strobe includes a control unit 10, a strobe unit 20, an EEPROM unit 30, a display unit 40, and first to fourth switches 51 to 54.
[0040]
The control unit 10 controls all functions of the camera SN with a built-in strobe, and includes a microcomputer (microcomputer) (described later). The strobe unit 20 is a device for performing auxiliary illumination when there is no auxiliary illumination and the brightness of the subject is difficult to perform appropriate photographing (described later).
[0041]
The EEPROM unit 30 is a non-volatile memory, and stores parameters such as a standard light emission time (or the number of times of light emission) and a framing correction time.
The parameters may be set by a user as shown in FIG. 2 (customization mode), or may be customized at a service center or the like. FIG. 2 is a diagram illustrating an example of the parameter correction mode.
The display unit 40 is made of a liquid crystal or the like, and is used for a film counter (see FIG. 2). Used by the user to confirm the photographed portion of the subject.
[0042]
The first switch (RL1) 51 and the second switch 52 (RL2) are switches for photographing.
The first switch 51 is a switch for “half-pressing of a photographing button”. When the first switch 51 is pressed, photometry, distance measurement, lens driving (focusing), and the like are performed.
Subsequently, when the second switch 52 for "pressing the photographing button" is pressed, the shutter is opened and closed, the lens is driven (returned to the initial position), the film is fed, and the flash is charged (other than in the flash disabled mode). The shooting operation ends.
[0043]
The third switch 53 is a zoom switch, 53a is a telephoto (zoom T) switch, and 53b is a wide (zoom W) switch (see FIG. 2). The fourth switch 54 is a switch used when correcting the parameters of the EEPROM unit 30.
[0044]
Next, control of the flash unit 20 by the control unit 10 will be described.
The flash unit 20 controls the light emission amount to correspond to two predetermined high voltage levels and low voltage levels in order to use the flash unit 20 for purposes other than illumination of the subject at the time of shooting (ie, pre-flash).
[0045]
That is, as shown in FIG. 3, when the pre-emission function (the framing assist function) is effective, even if the pre-emission is performed, the voltage level is higher than the normal charge level, which does not hinder the normal flash photography performed thereafter. Set. Conversely, when the pre-emission function is invalid, the level is set to a level at which a specified light emission amount capable of normal photographing can be secured.
Regarding the charge level, assuming that the normal photographable level is 300 V and the full charge level is 320 V, the charge level is set between them. That is, the charge level is set such that the charge voltage lost can be compensated for according to the setting state of the pre-light emission amount. Charging during the waiting time for framing is performed in the same manner.
The control unit 10 controls the light emission control terminal (sets the active level to the active level for a required time) so that the light emission amount can be freely controlled.
[0046]
Next, the operation of the present embodiment will be described with reference to FIGS.
FIG. 4 is a flowchart of this embodiment, and FIG. 5 is a diagram for explaining an example in which the issue time (number of times) and the waiting time are changed.
[0047]
As shown in FIG. 4, when the first switch (RL1) 51 is turned on (step S1), a check (BC) of a battery used for strobe light emission, lens driving, etc. is performed (step S2), and photometry is performed. (Step S3).
This photometric operation is for roughly measuring the luminance (subject luminance) of the entire photometric area. When the photometric sensor is divided into a plurality of portions, the determination is made by a sensor in the peripheral portion as much as possible, or the average luminance of the entire screen is measured.
[0048]
If the photometric result of the luminance level in step S3 is less than the reference value (here, LV3 or less (see FIG. 5)), it is determined that the state of the entire subject is not grasped by the finder (not shown) (step S4). : Less than the reference value), the flash unit 20 emits light for a short time (pre-emission), and illuminates the subject (step S5).
[0049]
As shown in FIG. 5, the light emission time here is longer (or the light amount is the same) and the light emission time is shorter when light is darker (for example, less than luminance level (LV) 0) as shown in FIG. The number of times of light emission is increased).
If it is relatively bright (for example, luminance level (LV) 4), the light emission time is shortened (or the number of times of light emission is reduced). The length of the light emission time and the like are stored as parameters in the EEPROM unit 30 as described above.
[0050]
After the strobe light is emitted, before a transition to a normal photographing operation, a waiting time of about 1 second is provided as a standard, and the waiting time is defined as a framing correction time (time secured by the user for correcting the framing). The length of the framing correction time and the like are stored as parameters in the EEPROM unit 30 as described above.
[0051]
Further, if the strobe capacitor is additionally charged using the framing correction time (strobe charging) to compensate for the energy lost due to light emission, it is possible to further increase the amount of light during actual shooting. (Step S6).
[0052]
If the first switch 51 is released after the pre-emission (step S7: $ FF), the photographing operation is interrupted, and the flash is immediately charged (step S17), so that the next framing can be performed. (Step S18).
[0053]
Even after the framing correction time, if the first switch 51 is pressed, a photographing operation such as regular photometry, distance measurement, and focusing is performed (step S7: $ N).
That is, photometry is performed (step S8), distance measurement is performed (step S9), strobe charging is performed as needed (step S10), and focus driving is performed (step S11).
[0054]
Then, when the second switch (RL2) 52 for "pressing the photographing button" is pressed (step S12: $ N), the following RL2 processing of steps S14 to S18 is performed (step S13).
That is, the shutter is opened and closed (step S14), focus driving is performed (step S15), film feeding is performed (step S16), flash charging is performed (step S17), and a series of photographing processes is ended (step S18). ).
[0055]
In step S12, if the second switch (RL2) 52 is $ FF (step S12: $ FF), if the first switch (RL1) 51 is $ FF (step S19: $ FF), the focus drive is returned. (Step S20), the process ends (Step S21).
[0056]
With the above-described configuration and processing, in spite of the fact that the subject is within a range where the photographing can be sufficiently performed as the distance measuring capability of the auto focus (AF) and the lighting capability of the strobe, the brightness cannot be sufficiently confirmed with the viewfinder. Because of this, it is possible to prevent failures such as insufficient framing or out-of-focus AF measurement range, resulting in a failed photograph such as defocus or overexposure (under).
[0057]
Also, there is no need to add parts to the conventional configuration, and a natural operation feeling can be obtained in a series of shooting flows, so that practical usability can be improved without increasing costs. It becomes.
[0058]
In addition, parameter data such as a light emission time (number of times) and a waiting time are stored in a nonvolatile memory (EEPROM). For example, when a parameter correction mode is provided and a parameter setting mode is set, a zoom button or the like is used. Thus, a more practical configuration can be achieved in accordance with the usability of each user.
[0059]
If the subject is very dark in the flow of a series of photographing, rough framing is performed first, the subject is reconfirmed by pre-emission, and after framing is corrected, main photographing can be performed.
[0060]
Therefore, the framing is conventionally moderately controlled when the subject is dark, and in the worst case, the situation in which the subject is shifted from the AF frame and becomes out-of-focus photograph can be reduced. In addition, even when the strobe is not used, the framing assist function can be used. By repeatedly turning on and off the first switch 51, the framing can be corrected as many times as possible to take an accurate photograph. Becomes possible.
[0061]
Although the case of the silver halide film has been described in the above embodiment, the present invention is naturally applicable to a digital camera having a display device including a liquid crystal or the like in a finder.
[0062]
【The invention's effect】
As described above, according to the present invention, the following effects can be exerted.
According to the first aspect of the present invention, when the photometry result at the time of photographing is lower than the predetermined luminance, pre-flash is performed, and normal photographing processing is performed after a predetermined time elapses. When the subject is dark and cannot be confirmed well, the arrangement of the subject on the viewfinder can be sufficiently confirmed during the secured predetermined time.
[0063]
Therefore, unsuccessful photographs such as defocus and overexposure (under) due to unconfirmed object arrangement on the viewfinder can be prevented. In addition, since the pupil opening is reduced by the pre-emission, so-called red-eye can be prevented.
[0064]
According to the second aspect of the present invention, it is possible to prevent the strobe from emitting light. Therefore, if the subject viewed through the finder is dark and cannot be confirmed well, the subject is displayed on the finder during the secured predetermined time. Can be confirmed enough. Therefore, unsuccessful photographs such as defocus and overexposure (under) due to unconfirmed object arrangement on the viewfinder can be prevented. Further, since the pupil opening is reduced by the pre-emission, red eyes can be prevented.
[0065]
According to the third aspect of the invention, the amount of pre-emission light can be changed by changing the pre-emission light-emission time and the number of times of light emission, so that wasteful consumption of the battery can be prevented.
According to the fourth aspect of the invention, the emission time of the pre-emission can be changed according to the luminance level (the measured luminance) based on the result of the rough emission, so that wasteful consumption of the battery can be prevented.
[0066]
According to the invention described in claim 5, for example, even when the subject cannot be sufficiently confirmed by one pre-flash, the subject can be sufficiently confirmed by repeating the pre-flash several times. Therefore, there are no failed pictures.
[0067]
According to the invention of claim 6, since the light amount of the pre-emission is stored in the light emission amount storage means and the stored value (set value) can be changed, the stored value can be changed by a user or a clerk of a camera service store, for example. If it is changed, it is possible to perform the user's favorite shooting.
[0068]
According to the seventh aspect of the present invention, for example, an existing zoom button is used as a mode in which the amount of pre-emission light can be adjusted, so that an increase in the cost of the camera can be suppressed and the amount of pre-emission light can be set conveniently. .
[0069]
According to the eighth aspect of the present invention, the waiting time after the pre-emission can be changed according to the user's preference, so that framing that the user is satisfied can be performed.
According to the ninth aspect of the present invention, the stored value of the waiting time after the pre-emission of the waiting time storing means can be changed, so that the framing that the user is convinced can be performed.
[0070]
According to the tenth aspect of the present invention, as the mode in which the waiting time after the pre-emission can be adjusted, for example, an existing zoom button is used, an additional button is not required, suppressing an increase in camera cost, and The amount of pre-emission light can be set conveniently.
[0071]
According to the eleventh aspect of the present invention, the additional charging of the strobe power storage unit is performed during the waiting time after the pre-emission, so that a decrease in the emission amount during the main emission can be suppressed.
According to the twelfth aspect of the invention, when the framing assist function is effective, the charging is performed at a higher charge level than usual, so that a decrease in the light emission amount during the main light emission can be suppressed.
[0072]
According to the thirteenth aspect, after the framing assist function is used, when the switch for half-pressing the photographing button is set to FF, the photographing is interrupted and the electric storage means for the strobe is charged. Thus, the strobe charging device can be charged for the strobe, and a sufficient amount of light for strobe light emission can be secured.
[Brief description of the drawings]
FIG. 1 is a block diagram of an embodiment of the present invention.
FIG. 2 is a diagram showing an example of a parameter correction mode in the embodiment.
FIG. 3 is a diagram illustrating a charge level to a strobe capacitor in the embodiment.
FIG. 4 is a flowchart in the embodiment.
FIG. 5 is a diagram illustrating an example in which a light emission time (number of times) and a waiting time are changed in the embodiment.
[Explanation of symbols]
SN Camera with built-in strobe 10 Control unit 20 Strobe unit 30 EEPROM unit 40 Display unit 51 First switch 52 Second switch 53 Third switch 53a Telescopic switch 53b of third switch Wide switch 54b of third switch Fourth switch

Claims (13)

In cameras with built-in flash with both pre-flash and normal flash functions,
1. A camera with a built-in flash, wherein a pre-emission is performed when a photometric result at the time of photographing is lower than a predetermined luminance, and a normal photographing process is performed after a predetermined time has elapsed. The camera with a built-in strobe according to claim 1,
A built-in flash camera that performs pre-flash even when no flash is used during shooting. The camera with a built-in strobe according to claim 1,
A strobe built-in camera, wherein a light amount of the pre-emission can be changed. The camera with a built-in strobe according to claim 3,
A camera with a built-in strobe, wherein a light amount of the pre-flash is changed according to a measured luminance. The camera with a built-in strobe according to claim 3,
A camera with a built-in strobe, wherein the number of times of the pre-emission is changed according to the measured luminance. The camera with a built-in strobe according to claim 3,
A strobe built-in camera, wherein the light amount of the pre-emission is stored in a light-emission amount storage means, and the light amount of the pre-emission is adjustable. The camera with a built-in strobe according to claim 3,
A camera with a built-in strobe, comprising a mode for adjusting the light amount of the pre-flash. The camera with a built-in strobe according to claim 1,
A strobe built-in camera, wherein a waiting time after the pre-flash is changeable. The camera with a built-in strobe according to claim 8,
A camera with a built-in flash, wherein the waiting time after the pre-emission is stored in a waiting time storage means, and the waiting time after the pre-emission is adjustable. The camera with a built-in strobe according to claim 8,
A camera with a built-in strobe, wherein the camera has a mode in which a waiting time after the pre-emission can be adjusted. The camera with a built-in strobe according to claim 8,
A camera with a built-in strobe, wherein the strobe power storage means is additionally charged during a waiting time after the pre-emission. The camera with a built-in strobe according to claim 11,
A camera with a built-in strobe characterized by setting a charge level higher than a normal charge level when the framing assist function is enabled. The strobe built-in camera according to claim 11 or 12,
A camera with a built-in flash, characterized in that if the switch for half-pressing the shooting button is set to "FF" after using the framing assist function, the shooting is interrupted and the storage device for the flash is charged.

Images