JPH0922041A - Camera system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system capable of obtaining a satisfactory photograph at photographing using artificial illumination under high luminance. SOLUTION: This system is provided with a photometry circuit 19, an object distance detection circuit 20, a stroboscopic device 11, an exposure value calculating means (control circuit 18) for calculating a stop value and a shutter second value for obtaining appropriate exposure for an object luminance based on the photometric value by the photometry circuit 19, an emitted light quantity calculating means (control circuit 18) for calculating the emitted light quantity of the stroboscopic device 11 based on the stop value calculated by the exposure value calculating means 18 and a range-finding value from the object distance detection circuit 20, an exposure value changing means (control circuit 18) for changing the stop value, or the shutter second value calculated by the exposure value calculating means 18 in the case the emitted light quantity calculated by the emitted light quantity calculating means 18 is exceeding the maximum emitted light quantity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera system,
More specifically, the present invention relates to a camera system that shoots with artificial lighting.

[0002]

2. Description of the Related Art Conventionally, a technique for obtaining a good photograph by keeping a balance between a main subject and a background by using artificial lighting such as a strobe device in photographing with a relatively high brightness in the daytime, especially in the case of backlighting, has been available. It is well known. For example,
US Pat. No. 4,690,536 proposes a technical means for controlling the exposure so that the background is over a predetermined amount when backlight is detected in photography using a strobe device.

[0003]

However, the technical means proposed in the above-mentioned US Pat. No. 4,690,536 has a problem that the stroboscopic light does not reach the main subject depending on the aperture value and the main subject becomes under. It was Also, the US patent US Pat.
The technical means proposed in No. 6 does not consider whether the film used is a negative film or a reversal film, and does not take any measures depending on the type of these films.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a camera system that obtains a good photograph in photographing with artificial illumination under high brightness.

[0005]

In order to achieve the above object, a camera system according to a first aspect of the present invention comprises a photometric means for photometrically measuring a subject brightness and outputting a photometric value, and a photometric value for measuring a subject distance. Distance measuring means for outputting a distance value, artificial illuminating means for irradiating the subject with illumination light, and an aperture value for obtaining an appropriate exposure for the subject brightness based on the photometric value by the photometric means and Based on the exposure value calculation means for calculating the shutter speed value, the aperture value calculated by the exposure value calculation means, and the distance measurement value output by the distance measurement means, the light emission amount of the artificial illumination means is calculated. The light emission amount calculation means for calculating, and when the light emission amount calculated by the light emission amount calculation means exceeds the maximum light emission amount, the aperture value or the shutter speed value calculated by the exposure value calculation means is changed. Comprising the exposure value change means.

In order to achieve the above object, a camera system according to a second aspect of the present invention is the camera system according to the first aspect, wherein the exposure value changing means changes the aperture value or the shutter speed value. Has a light emission quantity changing means for changing the light emission quantity by the artificial lighting means.

In order to achieve the above object, a camera system according to a third aspect of the present invention comprises a strobe device and a photometric means capable of photometrically measuring at least the brightness of background light and the brightness of a main subject. If the exposure control value determined by the brightness of the main subject does not reach the predetermined exposure level even if the amount of light emitted by the strobe device is taken into consideration, the exposure level difference between the background and the main subject is a predetermined value. The exposure control value is shifted so that

In the camera system according to the first aspect, the photometric means measures the subject brightness and outputs the photometric value. Further, the distance measuring means measures the subject distance and outputs the distance measurement value. Further, the artificial lighting means irradiates the subject with illumination light. Then, the exposure value calculation means calculates the aperture value and the shutter speed value for obtaining the proper exposure for the subject brightness, based on the light measurement value obtained by the light measurement means. Further, based on the aperture value calculated by the exposure value calculation means and the distance measurement value output by the distance measurement means, the light emission amount of the artificial illumination means is calculated by the light emission amount calculation means. Then, when the light emission amount calculated by the light emission amount calculation means exceeds the maximum light emission amount, the aperture value or the shutter speed value calculated by the exposure value calculation means is changed by the exposure value changing means.

According to a second aspect of the present invention, in the camera system according to the first aspect, the artificial illumination means emits light when the aperture value or shutter time value is changed by the exposure value changing means. The amount is changed by the light emission amount changing means.

According to another aspect of the camera system of the present invention, the photometric means is capable of measuring at least the brightness of the background light and the brightness of the main subject, and the exposure control value determined by the brightness of the background light is If the predetermined exposure level is not reached even when the light emission amount of the strobe device is taken into consideration, the exposure control value is shifted so that the exposure level difference between the background and the main subject becomes a predetermined value.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a configuration of an electric circuit of a camera system according to an embodiment of the present invention.

This camera system drives a strobe device 11 that emits light toward a subject, a photometric circuit 19 that measures the luminance of the subject, a subject distance detection circuit 20 that detects the distance to the subject, and a focus lens 29. Lens drive circuit 21, a winding circuit 22 for winding the film 28, a focal length detection circuit 23 for detecting the focal length of the zoom lens, a shutter drive circuit 24 for driving the shutter at the time of exposure, and a continuous shooting mode. A mode setting unit 25 which is a mode switching unit for setting, a power switch SW1 for turning on and off the power of the camera, a release switch SW2 for inputting a photographing start signal, and a state such as the mode setting and the number of frames. And a status display unit 30 for displaying the charge control unit and a control unit for controlling the entire camera including these circuits. It is configured to include a control circuit 18 for performing.

The strobe device 11 has a power supply circuit 12 which is a charging means whose power supply output is controlled by the control circuit 18, and a main capacitor 13 which is connected to + and-output terminals of the power supply circuit 12 to be charged. The anode terminal is connected to the + output terminal of the power supply circuit 12, and the cathode terminal is connected to the insulated gate bipolar transistor (I
nsulated Gate Bipolar Tra
a flashlight emission tube 14 that is connected to the collector of a transistor (hereinafter, referred to as an IGBT) 16 and that discharges the charge charged in the main capacitor 13 by applying a trigger voltage to the trigger electrode to emit a flashlight. An output terminal is connected to the trigger electrode terminal of the flash light emitting tube 14, and a trigger circuit 15 for applying a trigger voltage to the flash light emitting tube 14 in response to a light emission signal from the control circuit 18, and a negative electrode terminal of the flash light emitting tube 14. The collector is connected to the -output terminal of the power supply circuit 12, the emitter is connected to the gate control circuit 17, and the gate is connected to the gate control circuit 17 to control the flash emission of the flash arc tube 14.
An output terminal is connected to T16 and this IGBT16, and the IGBT1 is turned on by a signal from the control circuit 18.
And a gate control circuit 17 for biasing the gates of the gates 6.

When the strobe device 11 is caused to emit light, a light emission signal from the control circuit 18 is simultaneously output to the trigger circuit 15 and the gate control circuit 17.

A photometry command signal is input from the control circuit 18 to the photometry circuit 19 to measure the subject brightness in order to determine the exposure for photographing, and the subject brightness signal obtained by the measurement is used. It is input from the photometric circuit 19 to the control circuit 18.

Further, the photometric circuit 19 has a central portion of the field, which is usually called divided photometry, and a light receiving sensor for dividing the periphery into two or more parts for photometry.

FIG. 2 is a front view showing an example of a photometric pattern in the photometric circuit 19.

The subject distance detecting means 20 includes:
A subject distance detection command signal is input from the control circuit 18 to detect the subject distance, and the detected subject distance signal is input to the control signal 18 from the subject distance detecting means 20.

The control circuit 18 receiving this subject distance signal outputs a lens drive signal to the lens drive circuit 21 to drive the focus lens 29 in order to adjust the focal length of the photographing lens, and the focus lens 29 is driven by a predetermined amount. Whether or not it is driven is input to the control circuit 18.

A film winding command signal is input from the control circuit 18 to the film winding circuit 22, and the film 28 is wound by one frame by this command, and the film 28 is rotated by one frame. A signal indicating the result of whether or not it is wound up is input to the control circuit 18.

A focal length detection command signal from the control circuit 18 is input to the focal length detection circuit 23 to detect the focal length of the zoom lens.
The detected focal length signal of the zoom lens is input from the focal length detection circuit 23 to the control circuit 18.

A shutter drive command signal is input from the control circuit 18 to the shutter drive circuit 24 to drive the shutter, and a signal indicating whether or not the shutter has been driven in a predetermined manner is input to the control circuit 18. It is like this.

Various exposure control modes are set by the mode setting means 25, and the mode signals are input to the control circuit 18.

The diaphragm control means 26 receives the calculated diaphragm value up to the control circuit 18 and controls the diaphragm.

Further, the shutter speed calculated by the control circuit 18 is input to the shutter control means 27 to control the shutter opening time.

Next, the operation of the strobe device 11 will be described.

First, the output of the power supply circuit 12 is controlled by a signal output from the control circuit 18, and the main capacitor 13 is controlled by the power supply circuit 12.
Is charged.

The gate control circuit 17 biases and controls the IGBT 16 by a signal from the control circuit 18, and at the same time, the trigger circuit 15 sends a trigger signal to the flash arc tube 14 by a signal from the control circuit 18. Outputs the above main capacitor 13
By discharging the charged electric charge of the flash light emitting tube 14
Emits a flash of light.

Next, strobe charging control will be described.

FIG. 3 is a circuit diagram showing a more detailed structure of the strobe device 11.

As shown in the figure, a main capacitor 13 is provided at both ends of the power source E1 constituting the power source circuit 12, a power source boosting circuit 1 constituting the power source circuit 12 for boosting the voltage of the power source E1, and a main power source. The voltage detection circuit 2 for detecting the charging voltage of the capacitor 13 and the trigger circuit 15 are connected. The operations of the power supply booster circuit 1, the voltage detection circuit 2, and the trigger circuit 15 are controlled by the control circuit 18.

The power supply boosting circuit 1 includes a transistor Tr1 and Tr2, a resistor R5 and a transformer T, which are connected in series.
1 has a series circuit of a primary winding and a transistor Tr3, a secondary circuit of a transformer T1 and a series circuit of a resistor R6 and a rectifying fast recovery diode D1.

The resistor R1 is between the emitter and the base of the transistor Tr1 and the resistor R2 is between the transistor Tr1.
Of the transistor Tr2 and the CHG terminal of the control circuit 18, and the resistor R4 is connected between the collector of the transistor Tr2 and the base of the transistor Tr3.

The voltage detection circuit 2 has a resistor R7 and a resistor R7.
It is composed of a voltage dividing circuit by a series circuit of 8 and the connecting point of these resistors R7 and R8 is the control circuit 18
Is connected to the VST terminal.

Further, the trigger circuit 15 has a resistor R11.
A thyristor SCR1, resistors R9 and R10 connected to the gate of the thyristor SCR1, a capacitor C1 having one end connected between the resistor R11 and the thyristor SCR1 and a transformer T2 connected to the other end of the capacitor C1.
And is configured. The resistor R9 is connected to the STRG terminal of the control circuit 18.

A slow recovery diode D2 is connected between the voltage detection circuit 2 and the trigger circuit 15 to prevent the electric charge of the main capacitor 13 from leaking through the voltage detection circuit 2.

Between the both ends of the power source E1, a series circuit of a flash light emitting tube 14 and a gate control type semiconductor element (IGBT) 16, a series circuit of a resistor R13 and a Zener diode D3, and a cathode of the Zener diode D3. The collector of the transistor Tr4 is connected to the SCONT terminal of the control circuit 18 via the base resistor R15, and the resistor R14 connected between the base and the emitter of the transistor Tr4 is also connected. A resistor R12 is connected between the gate of the IGBT 16 and the cathode of the Zener diode D3.

Here, the slow recovery diode D
2 will be explained.

In the slow recovery diode D2, when positive and negative voltages are alternately applied, a current as described below flows.

Since the accumulated charge exists near the junction of the diode in which the current flows in the forward direction, even if a reverse bias current is suddenly applied, the accumulated charge is recombined and disappears. During this period, current flows in the opposite direction. The time during which the current flows in this reverse direction is called the reverse recovery time of the diode.

This reverse recovery time is fast in the fast recovery diode, and the diode used in the strobe circuit in the past was this fast recovery diode.

On the other hand, the slow recovery diode has a longer reverse recovery time than the fast recovery diode.

In order to produce this slow recovery diode, it is necessary to lengthen the carrier life, which is a major factor that determines the reverse recovery time of the diode. For this reason, the diffusion temperature of silicon is lowered and Increase impurity purity. Further, the capacity of the joint portion is increased by increasing the joint area.

In this embodiment, the strobe device 11 is constructed by using the slow recovery diode thus produced.

Next, referring to the flowchart of FIG.
The operation of the strobe device 11 will be described.

When the power switch SW1 is turned on (step S1), charging of the main capacitor 13 is first started (step S2). And the control circuit 1
8 monitors the voltage of the VST terminal (step S3),
When the VST terminal reaches the set voltage, the charging of the main capacitor 13 is stopped (step S4).

Now, it is assumed that the main capacitor 13 is already charged with a voltage of, for example, 300V. Here, when the release switch SW2 is turned on (step S
5) Start charging (step S6), operate the power supply booster circuit 1 for a short period of time, and start VS of the control circuit 18.
The voltage of the main capacitor 13 is checked by determining whether the T terminal is equal to or higher than a predetermined voltage (step S7).

This will be described in detail with reference to the time chart of FIG.

When the CHG terminal of the control circuit 18 is set to the low level, the power supply boosting circuit 1 operates and its output generates a voltage of 300 V in VMC1 (see FIG. 3). At this time, of course, VMC2 (see FIG. 3) is also 300V (actually, it is about 0.8 which is the voltage of the diode D2).
Although VMC1 becomes higher by V, it is ignored here. At the VST terminal of the control circuit 18, a voltage obtained by dividing the voltage of VMC1 by the resistors R7 and R8 is generated.

When a normal fast recovery diode is used for the diode D2, the waveform of VMC1 drops to about 200 V in accordance with the oscillation cycle of the power supply booster circuit 1 as shown by the dotted line in FIG. I will end up.

On the other hand, when the above slow recovery diode is used as the diode D2, a constant voltage (300 V) can be maintained as shown by the solid line in the figure, which is the same as when the fast recovery diode is used. There is no voltage drop.

This is for the reason explained below.

That is, a forward bias and a reverse bias are alternately applied to the diode D2 in accordance with the oscillation cycle of the voltage boosting circuit 1. At this time, in the fast recovery diode, at the moment when the reverse bias is applied, a slight current flows in the reverse direction only for the first short time, but thereafter, the reverse current does not flow. Therefore, at this time, the voltage of VMC1 drops.

On the other hand, when the slow recovery diode is used as the diode D2, current flows in the reverse direction while the reverse bias is applied. Therefore, this current flows through the resistors R7 and R8, and these resistors R7 and R8
A voltage is generated at both ends of VMC1 and VMC1 is maintained at the same voltage as VMC2.

That is, the characteristic of the slow recovery diode used here is that IR × R ≧ VMC2 is satisfied, where IR is the current flowing in the reverse direction and R is the series resistance value of the resistors R7 and R8. There is. For example, R = 10 MΩ, VMC
When 2 = 300V, IR ≧ 30 μA.

As described above, since the reverse current flows during the charging of the main capacitor 13, the main capacitor 13
It is possible that the charging time will be longer, but the current flowing in the reverse direction is several tens of microamperes, which is very small compared to the forward current, that is, the current that charges the main capacitor 13, and the increase in charging time is neglected. It's so small that it doesn't matter.

Thus, if the VST terminal of the control circuit 18 is equal to or higher than the predetermined voltage in step S7, the process shifts to the shutter sequence (step S8) and ends, otherwise release lock is performed (step S).
9).

Before explaining the operation of the present embodiment, exposure control using a strobe will be described with reference to FIGS. 6 and 7.

The photography using a strobe includes a stroboscopic photography under a low brightness and a stroboscopic photography under a comparatively high brightness. Especially, the latter is a daytime synchronized photography for a backlight or a main subject. It is generally known as a method used to soften the shadows and strong contrast of.

FIG. 6 is a diagram showing the photographed data in the daytime synchronized scene when the reversal film is used. In the figure, the horizontal axis ΔEVH represents the exposure difference with respect to the proper exposure in which the background exposure other than the main subject is obtained by the apex calculation, and the vertical axis ΔEVT represents the exposure difference with respect to the proper exposure of the main subject.

Incidentally, FIG. 6 plots points recognized as good photographs in various daytime synchronized scene live-actions. By the way, the data are photographs taken by reversal film.

The distribution of this data plot shows a slightly upper right distribution, the slope of the distribution is shown by the solid line, and the width of the distribution is shown by the dotted line.

Explaining this in detail, that is, when the background is properly exposed, the exposure of the main subject is about -0.6 EV relative to the proper exposure as a photograph, and when the background is +2 EV over. , Main subject exposure is ±
It shows that around 0 EV and proper exposure are beautiful as a photograph. That is, as the background exposure becomes overexposed, the exposure of the main subject is slightly increased, which is more beautiful as a photograph.

Next, the case of negative printing will be described with reference to FIG.

FIG. 7 shows the case of using a negative film.
It is the diagram which showed the photographed image data in a daytime synchronized scene. In the figure, the horizontal axis ΔEVH represents the exposure difference with respect to the proper exposure in which the background exposure other than the main subject is obtained by the apex calculation, and the vertical axis ΔEVT represents the exposure difference with respect to the proper exposure of the main subject.

As shown in FIG. 7, in the case of a negative print as well, the distribution shows a slope to the upper right as in the case of the reversal film, but this slope is larger than that of the reversal film.

The reason for this is that, in the case of negative printing, correction by printing is performed by a lab printer.

That is, when the background exposure is overexposed by the exposure control of the camera, the printer corrects negatively the printing of the entire photograph. Therefore, compared to reversal film, it is more beautiful to decide the exposure of the main subject by taking into account the amount of background exposure.

Next, the exposure control in the case of actually controlling with this exposure distribution will be described with reference to the conceptual diagram of FIG.

In FIG. 10A, if the main subject is EV1.
When 0 and the background is EV15, by adding strobe light, the exposure difference between the main subject and the background can be made ΔEV1. Here, the shaded area in the graph is the required amount of strobe light, but even if the maximum amount of light that can be controlled by the strobe is used and only the dotted line is filled, the exposure difference between the main subject and the background is greater than ΔEV1. turn into.

Therefore, in this case, as shown in FIG. 10 (b), the exposure of the background is shifted by the aperture or the shutter speed so as to be over ΔEV2 in accordance with the maximum light amount, so that the main subject and the background are shifted. The exposure difference can be maintained at a predetermined .DELTA.EV1 '.

Next, the actual exposure calculation in the camera system of this embodiment will be described.

When the slopes of the distributions shown in FIGS. 6 and 7 are expressed by a function, (a) in the case of reversal film It is.

In the case of (b) negative film Becomes

In addition, an over /
The under amount is different between reversal film and negative film, and is ± 3.0 EV and ± 1.5, respectively, relative to the appropriate amount.
It is about EV.

Therefore, the exposure control in the daytime synchronization using the strobe device under the above-mentioned conditions is as follows. (C) In the case of the reversal film, the background exposure is within the range of ± 1.5 EV. Control to meet.

(D) In the case of a negative film, the background exposure is ±
Within a range not exceeding 3.0 EV, Control within the range that satisfies.

Next, the strobe light emission amount GV when exposed to strobe light using a negative film is determined under the condition shown in (d) above.

When the exposure difference for proper exposure with the constant light + strobe light is calculated, Becomes

By transforming this, Becomes

From (d) above, It is.

Here, It is.

Therefore, from the above equation and the above equations (1) and (2), Becomes

Then, the actual exposure control may be performed using this exposure formula. In this exposure formula, a table may be created based on a result calculated in advance and the table may be referred to without directly performing the calculation.

As an example of the control method, first, AV and TV that are appropriate for the background are input to the equation (3) to obtain GV. At this time, when GV or GVMAX is exceeded, that is, when the maximum flash emission amount is exceeded, the aperture is opened. In order to obtain the aperture opening amount at this time, GV = GVMAX may be set, and AV may be calculated backward from the equation (3), or the aperture may be opened little by little along the program diagram, for example, by 0.1 EV.
AV and TV may be adopted when V becomes equal to or lower than GVMAX. However, the amount of over-correction of the background should not exceed +3 EV. That is, ΔE
VH is limited to + 3EV.

Next, the stroboscopic light emission amount GV when exposed to stroboscopic light using a reversal film is set to the above (c).
Calculated under the conditions shown in.

The reversal film is similar to the case of using the negative film, So that Becomes

Then, the exposure control may be performed using the equation (4). However, the amount of over the appropriateness of the background is +
Do not exceed 1.5 EV. That is, ΔEVH
Limits +1.5 EV.

Next, the exposure control value calculation operation in the camera system of this embodiment will be described with reference to the flow chart shown in FIG.

First, AV and TV for which the background is appropriate are obtained from the program diagram based on the background luminance value BVH (step S11). Next, since the negative film and the reversal film have different exposure calculation formulas, the negative film and the reversal film are separated (step S1).
2). If it is a negative film, the GV value is obtained from the GV calculation formula (3) (step S13). Also,
If it is a reversal film, the GV value is obtained from the GV calculation formula (4) (step S14).

The GV value thus obtained is compared with the GVMAX value which is the maximum light amount of the strobe (step S15),
If it is less than GVMAX, it is compared with GVMIN which is the minimum amount of light that can be controlled by the strobe (step S22), and GV
If MIN or more, the exposure control operation is performed according to each value of GV, AV, and TV at this time. In addition, the above step S22
In the case of GVMIN or less, warning processing (step S23) for warning that overexposure will occur is performed.

On the other hand, in step S15, the GV
Since the strobe light does not reach the subject when the value is equal to or higher than MAX, the AV value, that is, the aperture is opened by 0.1 steps at this time (step S16). Also, the TV corresponding to the AV at this time is obtained from the program diagram (step S1).
7).

Next, the negative film / reversal film is discriminated (step S18), and in the case of the negative film, the overexposure allowable amount ΔEV of the background is set to + 3EV (step S19). In the case of reversal film, the background overexposure allowance ΔEV is + 1.5E.
It is set to V (step S20).

Next, the background over amount determined by the current AV and TV is compared with ΔEV. If ΔEV is less than ΔEV, the AV and TV at this time are used, and the steps S12, S13 and The GV value is calculated in S14.

Then, again, in steps S15 and S22, GVMAX and GVMIN are compared, and GVMAX is compared with GVMIN.
The steps S12 to S20 described above are squeezed by 0.1 steps each until VMAX or less and GVMIN or more.

However, when the background over amount becomes equal to or more than the set ΔEV, the AV, TV, and GV at that time are adopted (step S21).

Next, another exposure control value calculation operation in the camera system of this embodiment will be described with reference to the flowchart shown in FIG.

Basically, the operation is the same as the exposure control value calculation operation shown in FIG. 8, but the difference is that FIG.
Then, when the first calculated GV value exceeds GVMAX,
Although a loop for recalculating by opening 0.1 stops is being rotated, in the example shown in FIG. 9, GV is calculated before the GV value is calculated for the first time.
If MAX is likely to be exceeded, opening the aperture first will increase the probability of GVMAX or less in the subsequent GV calculation.

First, AV and TV for which the background is appropriate are obtained from the program diagram based on the background luminance value EVH (step S31). Next, AV + DV-1.3 is standard, and AV + DV-0.3 which is one step larger than this is GV.
When exceeding MAX (step S32), set the aperture to 0.5
Steps are opened (step S33). As a result, the probability of entering GVMAX in the first GV calculation afterwards becomes high, and even if it does not enter GVMAX in the first time, the number of times of subsequent recalculation loops can be reduced.

Incidentally, steps S34 to S45.
Corresponds to step S12 to step S23 in FIG. 8, and therefore description thereof will be omitted here.

As described above, according to the camera system of the present embodiment, stroboscopic photography is performed while maintaining the exposure difference between the background and the main subject at a value of a predetermined relational expression, so that relatively high brightness is achieved. Even in the lower part, the strobe light reaches the subject sufficiently and a good photograph can be obtained.

[Additional Remarks] According to the embodiments of the present invention described in detail above, the following configurations can be obtained. That is, (1) photometric means for measuring the subject brightness and outputting the photometric value, distance measuring means for measuring the subject distance and outputting the distance measuring value, and artificial lighting means for illuminating the subject with illumination light. When,
An exposure value calculation means for calculating an exposure control value for obtaining an appropriate exposure for the subject brightness based on the light measurement value by the light measurement means, and an exposure value calculation means for calculating the exposure control value or preset. A light emission amount calculation means for calculating the light emission amount of the artificial illumination means based on the aperture value and the distance measurement value output by the distance measurement means, and the maximum light emission amount calculated by the light emission amount calculation means. A camera system comprising: an exposure value changing means for changing the exposure control value calculated by the exposure value calculating means when the amount is exceeded.

(2) The photometric means has at least two light receiving elements for measuring the brightness of the main subject and the background, respectively, and the exposure value calculation means calculates the aperture value or the shutter speed based on the brightness of the background. The camera system according to (1) above, which calculates a time value.

(3) The light emission amount calculation means calculates the light emission amount that exceeds or underlies a predetermined number of steps from the proper exposure by emitting light in addition to the exposure amount of the main subject by the brightness. ) Camera system described in.

(4) The camera according to (1), further comprising a light emission amount changing means for changing the light emission amount by the artificial illumination means when the aperture value or the shutter speed value is changed by the exposure value changing means. system.

(5) When the aperture value or the shutter time value is changed by the exposure value changing means, the light emission amount by the artificial lighting means is changed so that the predetermined number of steps depends on the brightness with respect to the background. The camera system according to (3) above, which has an amount changing unit.

(6) The camera system according to (1), wherein the light emission amount calculation means changes the light emission amount according to the type of film used.

(7) The camera system according to (6), wherein the film used is a negative film or a reversal film, and the light emission amount is changed.

(8) The camera system according to (7) above, wherein the amount of light emission is changed so that the negative film is made larger than the reversal film.

(9) The camera system according to (1) above, which has limiter means for limiting the amount of change in the exposure value by the exposure value changing means.

(10) The camera system according to (9), wherein the limiter means has a value according to the latitude of the film.

(11) Photometric means for measuring the subject brightness and outputting the photometric value, distance measuring means for measuring the subject distance and outputting the measured distance value, and artificial illumination for illuminating the subject with illumination light. Means, and exposure value calculation means for calculating an aperture value and a shutter speed value for obtaining an appropriate exposure for the subject brightness, based on the photometric value by the photometric means,
According to the distance measurement value by the distance measurement means and the aperture value or shutter time value by the exposure value calculation means, the light emission amount of the artificial illumination means may be different depending on the type of film used. A camera system characterized by being made to be able to.

(12) The type of the above-mentioned film to be used is classified into a negative film and a reversal film.
The camera system according to 1).

(13) A strobe device and at least photometric means capable of photometrically measuring the brightness of the background light and the brightness of the main subject are provided, and the light emission amount of the strobe device is set to the background light and the brightness of the main subject. On the other hand, the daytime synchronizer is characterized in that it is controlled so as to correspond to the deviation from the proper exposure value.

(14) A strobe device and at least a photometric means capable of photometrically measuring the brightness of the background light and the brightness of the main subject are provided, and the strobe device has an exposure amount determined for the main subject by an exposure control value. The exposure control value and the light emission amount of the strobe device are controlled so that the difference between the exposure amount obtained by adding the exposure amount determined by the light emission amount and the background exposure amount determined by the exposure control value has a predetermined relationship. A daytime synchronizing device characterized by:

(15) The predetermined relationship is determined on the basis of the deviation of the exposure amount for the background from the proper exposure amount and the deviation of the exposure amount for the main subject from the proper exposure amount. The daytime synchronizing apparatus according to (14) above.

(16) A strobe device and a photometric means capable of measuring at least the brightness of background light and the brightness of a main subject are provided, and an exposure control value determined by the brightness of the background light is applied to the main subject. If the predetermined exposure level is not reached even considering the amount of light emitted from the strobe device, the exposure control value is shifted so that the exposure level difference between the background and the main subject becomes a predetermined value. Camera system to be used.

(17) The camera system according to (16), wherein the shift amount is changed according to the type of film.

According to the camera system described in (1) above, when the light emission amount of the artificial illumination light exceeds the maximum light emission amount, the exposure control value is changed. Can be secured.

According to the camera system described in (2) above, since the exposure level difference between the main subject and the background can be maintained properly, a beautiful photograph can be obtained.

According to the camera system described in (3) above, the exposure amount can be supplemented by not only natural light but also strobe light.

According to the camera system described in (4) above, since the light emission amount of the artificial illumination light is changed according to the change of the exposure control value such as the shutter speed value and the aperture value, a beautiful photograph can be obtained. it can.

According to the camera system described in (5) above, since the light emission amount is changed in consideration of the brightness of the background light, the exposure level difference between the background and the main subject can be appropriately maintained.

According to the camera system described in (6) above, the exposure level difference can be appropriately maintained depending on the type of film.

According to the camera system described in (7) and (8) above, since the negative film is printed,
Considering this point, an appropriate exposure level difference can be maintained.

According to the camera system described in (9) above, it is possible to prevent an unnatural photograph when the exposure control value is changed infinitely.

According to the camera system described in (10) above, the range of change of the exposure control value is determined in consideration of the latitude of the film, so that the optimum limit can be set.

According to the camera system described in (11) above, since the light emission amount of the artificial illumination is changed according to the latitude of the film, the light emission amount can be made appropriate according to the film.

According to the camera system described in (12) above, it is possible to obtain an appropriate light emission amount according to the characteristics of the negative film and the reversal film.

According to the daytime synchronizing apparatus described in (13) to (17) above, since the exposure level difference between the main subject and the background can be maintained properly, a beautiful photograph can be obtained.

[0132]

As described above, according to the present invention, it is possible to provide a camera system capable of obtaining a good photograph in photographing with artificial illumination under high brightness.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an electric circuit of a camera system according to an embodiment of the present invention.

FIG. 2 is a front view showing an example of a photometry pattern in a photometry circuit of the camera system of the above embodiment.

FIG. 3 is a circuit diagram showing a more detailed configuration of a strobe device in the camera system of the embodiment.

FIG. 4 is a flowchart showing an operation of a strobe device in the camera system of the above embodiment.

FIG. 5 is a timing chart illustrating the operation of detecting the main capacitor voltage of the flash device in the camera system of the above embodiment.

FIG. 6 is a diagram showing real shot data in a daytime synchronized scene when a reversal film is used.

FIG. 7 is a diagram showing live-action data in a daytime synchronized scene when a negative film is used.

FIG. 8 is a flowchart showing an exposure control value calculation operation in the camera system of the above embodiment.

FIG. 9 is a flowchart showing another example of the exposure control value calculation operation in the camera system of the above embodiment.

FIG. 10 is an explanatory diagram illustrating exposure control of a main subject and a background when a negative film is used in the camera system of the above embodiment.

[Explanation of symbols]

 11 ... Strobe device 18 ... Control circuit 19 ... Photometric circuit 20 ... Subject distance detection circuit

Claims (3)

[Claims] 1. A photometric means for measuring subject brightness and outputting a photometric value, a distance measuring means for measuring a subject distance and outputting a distance measured value, and an artificial lighting means for irradiating a subject with illumination light. And an exposure value calculation means for calculating an aperture value and a shutter speed value for obtaining an appropriate exposure for the subject brightness, based on the photometry value by the photometry means, and the exposure value calculation means. A light emission amount calculation means for calculating the light emission amount of the artificial illumination means based on the aperture value and the distance measurement value output by the distance measurement means, and the light emission amount calculated by the light emission amount calculation means is the maximum. An exposure value changing means for changing the aperture value or the shutter speed value calculated by the exposure value calculating means when the light emission amount is exceeded, 2. The camera according to claim 1, further comprising a light emission amount changing device that changes a light emission amount of the artificial lighting device when the aperture value or the shutter speed value is changed by the exposure value changing device. system. 3. A strobe device, and a photometric unit capable of measuring at least the brightness of background light and the brightness of a main subject, wherein an exposure control value determined by the brightness of the background light is set to the main subject. If the predetermined exposure level is not reached even considering the amount of light emitted from the strobe device, the exposure control value is shifted so that the exposure level difference between the background and the main subject becomes a predetermined value. Camera system.