JP3002745B2 - Electronic camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to an electronic camera for recording on a recording medium.

(Related Art) In recent years, an electronic camera that converts an optical image incident through a lens into an electric signal by opening and closing a shutter and stores the electric signal as a still image on a recording medium has been used. And
The image stored on the recording medium is later reproduced by a cathode ray tube (CRT), etc., but taking into account the characteristics of the reproducing CRT, the recording is performed so that the overall characteristics including the characteristics are just linear. Correction is performed according to a predetermined gamma characteristic at the time of storage in a medium.

In such an electronic camera, the contrast between a normal shooting and a shooting using an illumination such as a strobe may greatly differ depending on the position of a subject or the like. For example, in the case of flash photography, a phenomenon occurs in which a subject located before an appropriate exposure position is white and the background is crushed black. As a configuration for preventing such a phenomenon, for example, a configuration described in JP-A-59-196664 is known.
Japanese Patent Application Laid-Open No. Sho 59-196664 discloses that when photographing is performed using a lighting device such as a strobe, the gamma characteristic is automatically changed to a strobe photographing characteristic in preparation for strobe light emission, so that the image becomes white. Correction is made so as not to cause the phenomenon of bleeding or blackening.

As described above, in the case of flash photography, changing the gamma characteristic along with preparations, in other words, regardless of the photography conditions, a certain fixed gamma characteristic for the flash is forcibly applied at the time of flash photography. Means that. For this reason, even when the subject of interest is imaged with optimal exposure, correction is performed using a gamma characteristic different from that of normal shooting, and an unnatural image is reproduced.

In backlight shooting in the daytime, a daylight sync mode is used, which is a daylight synchro shooting in which a strobe light is emitted in an auxiliary manner. In this case, the screen background is captured with the optimal exposure, and the screen background of the optimal exposure is used. If the gamma characteristic of the portion is changed, the entire screen becomes slightly overexposed, and good image quality cannot be selected.

(Problems to be Solved by the Invention) As described above, in the case of flash photography, since the gamma characteristic is forcibly changed regardless of the photography conditions, an unnatural image may be obtained depending on the photography conditions.

The present invention has been made in view of the above problems, and has as its object to provide an electronic camera capable of giving a natural contrast to the entire screen under various conditions including flash photography.

[Configuration of the invention]

(Means for Solving the Problems) In the electronic camera according to the first aspect, the shutter speed and the aperture value change in conjunction with each other within a predetermined range according to the luminance of the external light measured by the photometry circuit. It has a set automatic exposure control means, which emits light at the time of shooting using a strobe, converts an optical image incident through a lens by opening and closing a shutter into an electric signal, and has a predetermined gamma characteristic. In an electronic camera for recording on a recording medium by correcting to a value in consideration of characteristics on the reproduction side, the gamma characteristic is increased by a standard characteristic for normal photographing and a small signal component mainly corresponding to a signal darker than the standard characteristic. A gamma characteristic control circuit that changes the correction characteristics set as described above, a distance detection circuit that detects the shooting distance of the subject,
A data setting circuit for setting a guide number of the strobe; an aperture value F (FM) obtained by dividing the guide number of the strobe set in the data setting circuit by a photographing distance detected by the distance detection circuit; Comparing means for comparing an aperture value F (AE) determined by the automatic exposure amount control means from the luminance detected by the photometric circuit; and a comparison result obtained by the comparing means at the time of photographing using the strobe light, F (FM) ) ≧ F (AE), it is determined whether the luminance detected by the photometric circuit is within the interlocking range of the automatic exposure amount control means. If there is a hillside emission control means for giving a control command for correcting characteristics to the gamma characteristic control circuit, a comparison result by the comparison means at the time of photographing using the strobe is F (FM) ≧ F (AE). For, in which a control command to the gamma characteristic and the correction characteristic; and a summit emission control means for giving to the gamma characteristic control means.

An electronic camera according to claim 2, wherein the automatic exposure amount control means is set so that the shutter speed and the aperture value change in conjunction with each other within a predetermined range in accordance with the luminance of the external light measured by the photometric circuit. When shooting with a strobe, this strobe emits light, and by opening and closing the shutter, an optical image incident through a lens is converted into an electric signal, and a predetermined gamma characteristic is set to a value in consideration of characteristics on the reproduction side. In an electronic camera that corrects and records on a recording medium, the gamma characteristic includes a standard characteristic for normal photographing and a plurality of types of corrections set so as to raise small signal components corresponding to dark signals compared to the standard characteristic. A gamma characteristic control circuit for changing the characteristic, a distance detection circuit for detecting a shooting distance of the subject, a data setting circuit for setting a guide number of the strobe, The automatic exposure amount control based on an aperture value F (FM) obtained by dividing the strobe guide number set in the data setting circuit by the photographing distance detected by the distance detection circuit, and the luminance detected by the photometry circuit. Comparing means for comparing the aperture value F (AE) determined by the means, and detecting by the photometric circuit when the comparison result by the comparing means is F (FM) ≧ F (AE) at the time of photographing using the strobe. It is determined whether the obtained luminance is within the interlocking range of the automatic exposure amount control means. If it is within the interlocking range, the gamma characteristic is set as a standard characteristic. A hillside emission control means for obtaining a difference between the luminance detected by the circuit and a control command for a correction characteristic corresponding to the magnitude of the difference to the gamma characteristic control circuit; If the comparison result by the comparison means is not F (FM) ≧ F (AE), the difference in luminance between these aperture values F (FM) and F (AE) is obtained, and the correction characteristic corresponding to the magnitude of the difference is obtained. And a crest light emission control means for giving a control command to the gamma characteristic control circuit.

(Effect) In the electronic camera according to the first aspect, when shooting with a strobe, if the strobe emits light on the hillside, the surroundings are relatively bright, and if the brightness is within the interlocking range, the normal gamma characteristic is maintained. If the surroundings are dark and outside the interlocking range, the gamma characteristic is changed to a correction characteristic that pulls up a small signal component corresponding to a dark signal. By changing it, the contrast is always controlled to be natural for stroboscopic photography under various conditions.

In the electronic camera according to the second aspect, it is possible to change the gamma characteristic to a plurality of types of correction characteristics at the time of photographing using the strobe. The difference between the exposure control limit luminance determined by the range and the photometric luminance is obtained, and a correction characteristic according to the difference is applied. When the strobe emits light at the top of the mountain, the aperture value F (F
A difference in luminance between M) and F (AE) is obtained, and a correction characteristic according to the difference in luminance is applied to obtain an optimal gamma characteristic according to various photographing conditions, thereby controlling a more natural contrast.

(Embodiment) Hereinafter, an embodiment of an electronic camera according to the present invention will be described with reference to the drawings.

In FIG. 1, reference numeral 11 denotes a photographing lens, which is set to an appropriate photographing distance (subject distance) by a lens drive circuit 31. Reference numeral 12 denotes a shutter, which is controlled to be opened and closed by a shutter drive circuit 32.
An optical image is incident through the lens 11 by the opening and closing operation of the shutter 12.
More detected. 13 is a CCD as an image sensor
The CCD 13 converts the incident optical image into an electric signal. Further, the image sensor 13 is operated by the camera circuit 14,
The camera circuit 14 receives the electric signal converted by the CCD 13 and adjusts white balance based on a white balance control signal that is a voltage signal from the white balance circuit 15 and is controlled by a gamma characteristic control circuit 18. The electric signal, which is an image signal, is corrected by the gamma characteristic. 16 is a recording circuit, and a camera circuit.
An electric signal, which is an image signal output from 14, is recorded on a recording medium 17 such as a video floppy.

Also, 19 is a strobe, and this strobe 19 is a trigger circuit
By triggering the strobe circuit 21 by 20,
Light is emitted by the electric charges charged in the strobe circuit 21,
The charging voltage detection circuit 22 detects whether or not the flash circuit 21 has been charged with sufficient electric charge for the emission of the strobe light 19. Further, the guide number (GNo., ISO · m) of the strobe light 19 is set by the data setting circuit 23.

Further, reference numeral 25 denotes a distance detection circuit, which is based on a triangulation method used in an automatic focusing device or the like, and generates an output corresponding to a shooting distance to a subject (not shown) by manual setting. An output corresponding to the shooting distance is generated. Further, a luminance signal corresponding to the luminance of the external light is output from the photometric circuit 26, and a color temperature signal is output from the colorimetric circuit 27 corresponding to the color temperature of the external light.

Reference numeral 35 denotes a camera release switch. This camera release switch 35 has a contact S1 for distance measurement, photometry, and colorimetry command.
And command contact S2 for shutter release operation.
Is a strobe mode changeover switch.This strobe mode changeover switch 36 has a contact S11 for a strobe off mode, a contact S12 for an auto mode for automatically firing the strobe when external light is low in brightness, and a strobe on mode for forcibly firing the strobe. Contact S13.

Further, an output signal based on the command signal from the camera release switch 35 and the flash mode changeover switch 36 is transmitted to a system control circuit 3 formed by a CPU or the like.
7 to perform a predetermined calculation and give an operation command at a predetermined timing. The system control circuit 37 has, as a function, an automatic exposure control unit that changes the shutter speed and the aperture value in conjunction with each other based on the luminance signal from the photometry circuit 26. Also, the shooting distance signal from the distance detection circuit 25 and the guide number from the guide number data setting circuit 23
Based on the GNo., A function for obtaining an aperture value F (FM) by the following equation, and determined by the automatic exposure control means based on the obtained aperture value F (FM) and a luminance signal from the photometry circuit 26. A comparison means for comparing with the aperture value F (AE) to determine whether the strobe 19 emits light on the hillside, that is, F (FM) ≧ F (AE), or whether the strobe light is other than F (FM) ≧ F (AE). Have.

F (FM) = GNo. / Photographing distance [m] Further, there is provided white balance switching means for switching a white balance control signal according to the result of comparison by the comparison means. That is, in the case of hillside light emission in which the comparison result is F (FM) ≧ F (AE), a white balance control signal is generated at the time of strobe light emission, and the comparison result is F (FM) ≧
In the case of peak emission other than F (AE), the white balance circuit 15 is controlled so as to generate a white balance control signal for external light.

Further, the gamma characteristic control circuit 18 converts the gamma characteristic according to a command from the system control circuit 37 into a standard characteristic a for normal photographing shown in FIG. 4 and a small signal component mainly corresponding to a signal darker than the standard characteristic a. Are changed to the correction characteristics b and c set so as to be raised.

In order to give a command to the gamma characteristic control circuit 18, the system control circuit 37 is provided with a hillside light emission control means and a peak light emission control means.

If the comparison result by the comparison means is F (FM) ≧ F (AE), the hillside emission control means determines whether the luminance detected by the photometric circuit 26 is within the interlocking range of the automatic exposure control means, and If within the range, the gamma characteristic is set to the standard characteristic a,
If it is out of the interlocking range, a control command is given to the gamma characteristic control circuit 18 so as to make the correction characteristic b or the correction characteristic c. In addition,
Whether to use the correction characteristic b or the correction characteristic c is determined as follows. That is, the difference between the exposure control limit luminance determined from the interlocking range of the automatic exposure control means and the luminance detected by the photometry circuit 26 is obtained, and the correction characteristic b
Alternatively, the correction characteristic is set to c.

Then, when the comparison result by the comparison means is not F (FM) ≧ F (AE), the peak light emission control means gives a control command to the gamma characteristic control means to set the gamma characteristic to the correction characteristic b or the correction characteristic c. Whether to use the correction characteristic b or the correction characteristic c is determined as follows. That is, the aperture values F (FM), F
A difference in luminance at (AE) is obtained, and a control command is given to the gamma characteristic control circuit 18 to obtain a correction characteristic b or a correction characteristic c corresponding to the magnitude of the difference.

In addition, the system control circuit 37 controls the lens drive circuit 31 according to the above-described shooting distance, controls the shutter drive circuit 32 according to the timing described later, issues a trigger command to the strobe 19, Provided that the battery is charged to a sufficient value, the signal is supplied to the trigger circuit 20, and further, with the recording operation of the image signal by the recording circuit 16, the motor 39 is operated via the motor control circuit 38 and the head is operated. A function of moving the head by the movement control circuit 40 and storing data in the video floppy which is the recording medium 17 is provided.

FIG. 2 is a shutter program diagram showing the relationship between the aperture value FNo. (F (AE)) and the shutter speed T corresponding to the external light luminance EVi (i = 6 to 18). Accordingly, the aperture value FNo. And the shutter speed T change on the thick line.
This external light luminance EVi is detected by the photometric circuit 26 shown in FIG. 1, and is calculated by the automatic exposure control means by the system control circuit 37 based on the relationship shown in FIG. 2, and the result is output to the shutter drive circuit 32. You. The shutter drive circuit 32 drives the shutter 12 based on the result when the command contact S2 of the camera release switch 35 is turned on. In the example shown in FIG. 2, when the external light luminance is equal to or less than EV8, the aperture value becomes an open value with an aperture value of FNo. = 2.8, the shutter speed T becomes 1/30, and the shutter time becomes longer. It is set so that there is nothing. This is to prevent camera shake, and the dark current of the CCD 13 increases and S
/ N is prevented from decreasing. And below the brightness EV,
When the auto flash mode is set by the flash mode switch 36, the flash 19 automatically emits light during shooting.

Next, the relationship between the shutter opening state and the flash timing at the time of flash shooting will be described with reference to FIG.

FIG. 3 shows a shutter opening waveform in the case of external light luminance EV12. That is, when the brightness is EV12, the second
From the relationship shown in the figure, the shutter speed T is 1/125 and the aperture value FNo.
It becomes 5.6. Therefore, when the shutter is released, the first
The shutter 12 shown in the figure starts the opening operation, and this time is detected by the home switch 33, and as shown in FIG.
After 8 [msec], the maximum opening FNo. = 5.6.

Now, it is assumed that the strobe on mode in which the contact S13 of the strobe mode switch 36 is turned on and the strobe 19 is forcibly emitted is set. In this state, a case where a subject at a shooting distance of 1.25 m is photographed and a case where a subject at a shooting distance of 2.5 m is photographed will be described. Note that the guide number GNo. Of the strobe 19 is 10.

In the case of a subject at a shooting distance of 1.25 m An aperture value FNo. (F (FM)) obtained from the shooting distance and the strobe guide number GNo. Is F (FM) = 10 / 1.25 m = 8.0.

In contrast, the aperture value FNo.
(F (AE)) is 5.6, and the relationship between the two is F (FM) ≧ F
(AE). In this case, the strobe light 19 emits light synchronously with an aperture value FNo. = 8 in the middle of the opening of the shutter 12. This is the hillside light emission described above. By this hillside light emission, the subject is irradiated from the strobe 19 with an appropriate amount of light. The background subject has an appropriate exposure at FNo. = 5.6 and T = 1/125 sec.

In this case, an appropriate amount of light is given by a strobe to the main subject at a shooting distance of 1.25 m. Also, since the background subject also has an appropriate exposure as described above, the gamma characteristic remains the standard characteristic (γ = 0.45).

In the case of a subject at a shooting distance of 2.5 m The aperture value FNo. (F (FM)) obtained from the shooting distance and the strobe guide number GNo. Is F (FM) = 10 / 2.5 m = 4.0.

In contrast, the aperture value FNo.
(F (AE)) is 5.6, and F (AE) is F (FM)
Since the aperture is larger and the aperture is smaller, the strobe emits light synchronously with the maximum aperture FNo. = 5.6 in FIG. This is the peak emission described above.

In this case, a proper amount of light is not emitted from the strobe 19 to the main subject located at a position at a shooting distance of 2.5 m, but rather is emitted as auxiliary light of external light. That is, the background is properly exposed,
The main subject is underexposed. Therefore, the correction characteristic b shown in FIG. 4 is applied as the gamma characteristic. As shown in the drawing, the correction characteristic b is set so as to mainly pull up a small signal component corresponding to a dark signal, so that an output image close to an appropriate contrast can be obtained for both the background and the subject.

Note that among the gamma characteristics shown in FIG. 4, the standard characteristic is set to γ = 0.45 as described above. On the other hand, as shown by the broken line, the correction characteristic b is set to γ = 0.3 to 0.35 when the incident light amount is 50% white or less, and is set to γ = 0.35 to 0.45 when the incident light amount is 50% white or more. For this reason, gamma is applied so that the output voltage at the time of the 12% white incident light amount in the correction characteristic b becomes the same output voltage as the 20% white incident light amount at γ = 0.45 of the standard characteristic a. It has risen by 0.7 EV. On the other hand, on the high luminance side, the 63% white incident light amount in the correction characteristic b is
The output voltage is the same as the 70% white incident light quantity of γ = 0.45 in the standard characteristic a, and the increase is kept to about 0.1 EV.
That is, as described above, the setting is such that the small signal component mainly corresponding to the dark signal is raised.

Also, although not shown, the subject is farther away from 3.
At 57m, proper aperture F (FM) for strobe light = 2.8
And an aperture F (AE) = 5.6 determined from the output of the photometry circuit 26, there is a difference equivalent to 2 EV.
EV under exposure. Therefore, at this time, the correction characteristic c shown in FIG. 4 is applied as the gamma characteristic, and the main subject is corrected so that the output image is close to the optimal exposure.

The correction characteristic c is set to γ = 0.26 to 0.3 when the incident light amount is 50% white or less, and γ = 0.3 to 0.45 when the incident light amount is 50% white or more. Therefore, as shown by the broken line in FIG. 4, the incident light amount of 6% Hawaiiite has the same output voltage as the 20% white incident light amount at γ = 0.45 which is the standard characteristic. That is, it is rising by about 1.7 EV. On the other hand, on the high luminance side, the incident light amount of 60% white in the correction characteristic c is
The output voltage is the same as the 70% white incident light quantity of γ = 0.45, which is the standard characteristic a, and the increase is limited to about 0.2 EV. That is, the setting is made so that the small signal component mainly corresponding to the dark signal is increased more.

 Next, the operation will be described with reference to FIG.

First, when the camera release switch 35 shown in FIG. 1 is operated and its contact S1 is turned on, various information is input to the system control circuit 37. That is, the luminance information EVi is input, and the aperture value F (AE) is obtained from the relationship shown in FIG. 2 (steps 101 and 102). Further, information regarding the shooting distance and the guide number GNo. Of the strobe light 19 is input (step 103, step 104), and the aperture value F (FM) is obtained from these (step 105). And
A difference F (γ) between these two aperture values F (FM) and F (AE) is obtained (step 106).

Further, since a signal is also input from the flash mode changeover switch 36 (step 107), step 108, step
At 109, it is determined which mode is set. In the strobe-on mode, which is the forced strobe mode, and in the auto mode, it is determined whether or not the external light luminance is equal to or less than EV8 (step 110), and the flash mode is set (step 111).

Further, in the case of the strobe light emission mode, the aperture value F (F
M) and F (AE) (step 113), and F (γ) ≧ 0,
That is, if F (FM) ≧ F (AE), the hillside emission mode (step 116) is set. On the other hand, if F (γ) ≧ 0, that is, if F (FM) ≧ F (AE), the peak emission mode (step 114) is set.

On the other hand, in the mountainside mode (step 116),
It is determined whether or not the luminance detected by step 6 falls within the interlocking range of the automatic exposure amount control means, an aperture value of F2.8, a shutter speed of 1/30 seconds or an aperture value of F16, 1/1000 seconds (step 117).
If it is within the interlocking range, both the main subject and the background are properly exposed, so the gamma characteristic is set to the standard characteristic a (step 122). On the other hand, if it is out of the interlocking range, the main subject is properly exposed by the strobe. Since the background is under, the gamma characteristic is set to the correction characteristic b or the correction characteristic c. In determining whether to use the correction characteristic b or the correction characteristic c, first, a difference between the exposure control limit luminance determined from the interlocking range of the automatic exposure control means and the luminance detected by the photometry circuit 26 is obtained (step 118). . And
It is determined whether the magnitude of this difference is under 1 EV or more (step 119). If it is less than 1 EV, the correction characteristic b is applied as the gamma characteristic (step 120), and if it is 1 EV or more, the correction characteristic c is applied (step 121).

In the case of the peak mode (step 114), the main subject is underexposed, so that the gamma characteristic is set to the correction characteristic b or the correction characteristic c.
Find the difference in luminance between (FM) and F (AE) (step 115)
The magnitude of the difference is determined in step 119, and the gamma characteristic is determined to be the correction characteristic b or the correction characteristic c according to the magnitude (steps 120 and 121).

On the other hand, if it is determined in step 108 that the flash mode is not in the strobe off mode, and if it is determined in step 110 that the external light luminance is higher than EV8 in the auto mode, the flash mode is set to the non-flash mode (step 112). The standard characteristic a is applied as the characteristic (step 122).

Thereafter, when the command contact S2 of the camera release switch 35 is turned on and the shutter 12 is released, the home switch 33 detects the start time of its operation, and in the case of the strobe light emission mode, the strobe 19 is triggered after a predetermined time, Emit hillside light or peak light.

The subject image is converted into an electric signal by the image sensor 13 by the release, is controlled to an appropriate color balance in the camera circuit 14, is corrected by the gamma characteristic, and is recorded on the recording medium 17 via the recording circuit 16.

Here, as the time from the start of the shutter release to the flash trigger, a time value up to a predetermined opening FNo. Stored in the system control circuit 37 for each shutter speed in advance is used.

According to the above configuration, at the time of flash shooting, even under shooting conditions in which the amount of strobe irradiation with respect to the main subject is insufficient, or under the shooting conditions in which the strobe irradiation amount is appropriate but the background is under, the entire screen is not affected. Since the gamma characteristic is changed so as to make the contrast appropriately close, a good image can be obtained. In particular,
By optimally selecting from a plurality of gamma characteristics according to the under value, the quality of the captured image can be further enhanced. If both the main subject and the background have proper exposure,
Without changing the gamma characteristic unnecessarily, it has the same gamma characteristic as in normal flash off mode shooting,
As in the conventional case, the gamma characteristic is forcibly changed at the time of flash photography, and the quality is not impaired.

As a result, unlike a silver halide film, the quality of a video signal image having a narrow latitude can be significantly improved.

In the above embodiment, the strobe mode is set to the switch 36.
Is selected by the user, but it is also possible to use a photometric circuit having an automatic backlight detection function to perform automatic daylight strobe emission. The recording medium 17 may be anything other than magnetism, such as magneto-optical, optical, or solid-state memory, and can be applied to any device that records images. Any device or element for converting an optical image into an electric signal, such as an image pickup tube, may be used. Further, the strobe device can be either a built-in type or an external type. In addition, the selection of the gamma characteristic may be performed at the time of flash photography, after imaging by CCD or the like is completed and immediately before recording on a recording medium. Further, the above description
Although the exposure is performed when either the strobe light amount or the background is appropriate exposure, if both are under exposure, the gamma characteristic may be changed according to the degree.

〔The invention's effect〕

According to the electronic camera of the first aspect, when shooting with a strobe, when the strobe emits light on the hillside, when the surroundings are relatively bright, the normal gamma characteristic is used, and when the surroundings are dark, the gamma characteristic is used. The gamma characteristic is changed to the correction characteristic even when the strobe emits light at the peak, by changing the correction characteristic to raise the small signal component corresponding to the dark signal.
Since the contrast is always controlled to be natural for stroboscopic photography under various conditions, the quality of the photographed image can be improved.

According to the electronic camera of the second aspect, it is possible to change the gamma characteristic to a plurality of types of correction characteristics at the time of photographing using the strobe, and when the strobe emits hillside light and the photometric luminance is out of the interlocking range, The difference between the exposure control limit luminance determined by this interlocking range and the photometric luminance is obtained, and a correction characteristic according to the difference is applied. When the strobe emits light at the top of the mountain, the aperture value F (FM) or F (AE) is used. A difference in luminance is obtained, and a correction characteristic according to the difference in luminance is applied to obtain an optimum gamma characteristic according to various photographing conditions, and the contrast is controlled to be more natural, so that the quality of a photographed image can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of an image recording apparatus according to the present invention, FIG. 2 is a program diagram showing a relationship between a shutter speed and an aperture value with respect to external light luminance, and FIG. FIG. 4 is a timing chart showing the relationship with the strobe light emission timing, FIG.
FIG. 5 is a flowchart illustrating the operation of the present invention. 11 ... Lens, 12 ... Shutter, 17 ... Recording medium, 18 ...
… Gamma characteristic control circuit, 19… Strobe, 23… Guide number data setting circuit, 25… Distance detection circuit, 26… Photometry circuit, 37… Comparison means, hillside emission control means, and peak emission control means System control circuit.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04N 5/225 Z H04N 5/225 F H04N 5/238 Z H04N 5/202

Claims (2)

(57) [Claims] An automatic exposure amount control means for setting a shutter speed and an aperture value to change in conjunction with each other within a predetermined range in accordance with luminance of external light measured by a photometric circuit;
At the time of shooting using a strobe, the strobe emits light, and the optical image incident through the lens is converted into an electric signal by opening and closing the shutter, and the value is corrected to a value considering the characteristics on the reproduction side by a predetermined gamma characteristic. An electronic camera for recording on a recording medium, wherein the gamma characteristic is changed to a standard characteristic for normal photographing and a correction characteristic set so as to increase a small signal component mainly corresponding to a dark signal compared to the standard characteristic. A characteristic control circuit, a distance detection circuit that detects a shooting distance of the subject, a data setting circuit that sets a guide number of the strobe, and a guide number of the strobe set in the data setting circuit is detected by the distance detection circuit. From the aperture value F (FM) obtained by dividing by the photographing distance and the luminance detected by the photometric circuit, the automatic exposure amount Comparing means for comparing the aperture value F (AE) determined by the control means; and when the comparison result obtained by the comparing means at the time of photographing using the strobe is F (FM) ≧ F (AE), the photometric circuit is used. It is determined whether the detected brightness is within the interlocking range of the automatic exposure amount control means. If the detected brightness is within the interlocking range, the gamma characteristic is set to the standard characteristic, and if the detected luminance is out of the interlocking range, a control command to set the correction characteristic is issued to the gamma characteristic control. A hillside light emission control means provided to a circuit; and a control command for setting a gamma characteristic to the correction characteristic when the comparison result by the comparison means is not F (FM) ≧ F (AE) at the time of photographing using the strobe. An electronic camera, comprising: a peak light emission control unit provided to the control unit. 2. An automatic exposure amount control means wherein a shutter speed and an aperture value are set so as to change in conjunction with each other within a predetermined range in accordance with the luminance of external light measured by a photometric circuit,
At the time of shooting using a strobe, the strobe emits light, and the optical image incident through the lens is converted into an electric signal by opening and closing the shutter, and the value is corrected to a value considering the characteristics on the reproduction side by a predetermined gamma characteristic. In an electronic camera for recording on a recording medium, the gamma characteristic is divided into a standard characteristic for normal photographing and a plurality of types of correction characteristics set so as to mainly extract a small signal component corresponding to a dark signal compared to the standard characteristic. A gamma characteristic control circuit for changing; a distance detection circuit for detecting a shooting distance of a subject; a data setting circuit for setting a guide number of the strobe; and a distance detection circuit for setting a guide number of the strobe set in the data setting circuit. From the aperture value F (FM) obtained by dividing by the shooting distance detected by the camera and the luminance detected by the photometry circuit. A comparing means for comparing an aperture value F (AE) determined by an amount control means; and a photometric circuit when a comparison result by the comparing means at the time of photographing using the strobe is F (FM) ≧ F (AE). It is determined whether the brightness detected by the automatic exposure amount control means is within the interlocking range, if it is within the interlocking range, the gamma characteristic is a standard characteristic, and if it is outside the interlocking range, the exposure control limit brightness determined from the interlocking range is determined. Calculating a difference between the luminance detected by the photometric circuit and a control command for setting a correction characteristic corresponding to the magnitude of the difference to the gamma characteristic control circuit; and When the comparison result by the comparing means is not F (FM) ≧ F (AE), these aperture values F
(FM) and F (AE), and a peak emission control means for obtaining a control command for a correction characteristic corresponding to the magnitude of the difference to the gamma characteristic control circuit. Electronic camera.