JPH0664283B2 - Modeling dimming method for electronic flash - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a modeling dimming method for an electronic flash including a plurality of lamps provided with a discharge tube that emits instantaneous light and an incandescent lamp that emits constant light. It is about.

(Prior Art) In a photo studio or shooting that requires a large amount of light, a large electronic flash device is used to illuminate a subject.

FIG. 4 shows the configuration of an electronic flash device used in such a conventional illumination system.

This electronic flash device comprises a power supply unit 31 and a lamp 32. The lamp 32 has a discharge tube 33 such as a xenon discharge tube that emits instantaneous light at the time of shooting, and a constant light emission for observing the light distribution state with the naked eye. Incandescent light bulb 34
And are provided.

In addition, the power supply unit 31 includes a capacitor 35 that stores energy for instantaneous light emission, a triac 36 that dims the stationary light according to the energy, and dimming so that the illuminance of the stationary light is proportional to the instantaneous light. And a control circuit 37 for controlling.

When taking a picture, for example, a plurality of lamps are used to illuminate a subject, but before the image is taken, the proper arrangement of the lamps and the adjustment of the light amount are performed by constant light.

In this light amount adjustment, since it is impossible to determine the light emitting state with the naked eye with the instantaneous light from the discharge tube 33,
An incandescent light bulb 34 having an output proportional to the instantaneous light is used, and the state of hitting of the light ray, the shadow, the three-dimensional effect, the texture, etc. are observed to predict the state that will be reproduced on the film.

In this case, a dimming method is generally used in which the illuminance of each stationary light is reduced while maintaining the same ratio of the illuminance of the stationary light of each lamp and the illuminance of the instantaneous light of each lamp.

At this time, in many cases, the illuminance of the instantaneous light must be lowered as a whole in order to properly set the aperture value of the camera.

Next, a specific example of light amount adjustment will be described with reference to FIG.

In the figure, 41 is a camera for photographing the subject 42, and 43 is a back screen.

For example, four lamps 44, 45, 46 and a lamp 47 are arranged around the subject 42.

The discharge tubes of any of the lamps 44, 45, 46 and the lamp 47 have the maximum output, that is, the maximum accumulated power amount is 1200 W.S, and the output can be adjusted within the range of 30 steps per 1/6 diaphragm. .

On the other hand, as the incandescent light bulb in the lamps 44, 45, 46 and the lamp 47, for example, a halogen lamp is used, and a lamp capable of outputting a maximum of 200 W with respect to the maximum output of 1200 W.S of the discharge tube is used.

When a flash meter (not shown) is used to adjust the output of the electronic flash for the subject 42 so that the film sensitivity is ISO 100 and the lens aperture of the camera 41 is F8, the lamps 44, 45, 46, 47 are adjusted.
The output of each discharge tube and the output of each incandescent lamp linked to it are as shown in Table 1 below.

(Problems to be Solved by the Invention) However, in the conventional method, while the illuminance of the instantaneous light instantaneously releases the charging energy of the capacitor and emits light with high brightness, the continuous light emits light continuously. Lamps 44,4
Due to the structural restrictions of 5, 46 and 47, the lamp 4
There was a considerable difference between the illuminance level of the instantaneous light of 4, 45, 46, 47 and the illuminance level of the stationary light.

In addition, in the conventional method, when the illuminance is reduced, it becomes dark beyond the visible range and cannot be confirmed with the naked eye.

Therefore, the present invention has been made in view of the above circumstances,
We provide a modeling dimming method for electronic flash that automatically adjusts the illuminance of ambient light and the illuminance of ambient light at the same ratio, and automatically adjusts the illuminance of ambient light adjoining the brightest instantaneous light to the maximum. The purpose is to do.

(Means for Solving the Problems) As means for achieving the above object, the present invention uses a plurality of lamps provided with a discharge tube that emits instantaneous light and an incandescent bulb that emits constant light. It is an illumination method that illuminates the subject by adjusting the output of the discharge tube of the lamp, selects the brightest adjusted discharge tube of each discharge tube, and calculates the output of the selected discharge tube from the maximum set output. The data corresponding to the obtained shift amount is added to the incandescent lamp of each lamp, and automatically adjusted so that the output of the incandescent lamp of the lamp with the brightest discharge tube is maximized at the same time. The state can be confirmed with the naked eye and the writing can be easily performed.

(Function) Select the brightest specific discharge tube from each discharge tube, calculate the output of the specific discharge tube from the maximum set output, for example, subtract the amount of data corresponding to the shift amount obtained by subtracting each incandescent By automatically adjusting the output of each incandescent light bulb in addition to the light bulb, the subject can be illuminated brightly as a whole, making it very easy to see the subject with the naked eye. .

(Examples) Hereinafter, the present invention will be specifically described with reference to the illustrated examples.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

This embodiment shows a case where four lamps 1 are provided. In each lamp 1, 1, 1, 1 discharge tubes 2, 2, 2, 2 for emitting instantaneous light at the time of photographing and Incandescent light bulbs 3, 3, 3, 3 that emit constant light are provided side by side to adjust the light quantity.

Here, for example, a xenon discharge tube is used as the discharge tube 2, and a halogen lamp is used as the incandescent lamp 3.

The discharge tubes 2, 2, 2 and 2 are connected to a light amount discriminating circuit 4 for discriminating the light amount at the time of instantaneous light emission.

Further, the light amount determination circuit 4 is connected to the CPU 5.

The light amount determination circuit 4 is composed of a charging circuit, a control circuit, a comparator for comparing the light amounts of the discharge tubes 2, 2, 2, 2 and the like.

The CPU 5 receives the light amount signal from the light amount discriminating circuit 4, a discriminating unit for selecting the maximum light amount signal, that is, the maximum accumulated power amount, and outputs the output of the incandescent lamp 3 of each lamp 1, 1, 1, 1 of the discharge tube. It is composed of an output unit that adjusts the output in proportion to the output, a setting unit that maximizes the output of the incandescent lamp 3 that serves as a reference, and the like.

The change-over switch 8 is a switch that is connected to the CPU 5 and selects the method of proportionalizing the output of the discharge tube and the output of the incandescent lamp or the method of the present invention.

The CPU 5 is also connected to dimming circuits 6, 6, 6, 6 for adjusting the outputs of the incandescent lamps 3, 3, 3, 3.

The interlocking circuit 7 includes the discharge tubes 2, 2, 2 of the respective lamps 1, 1, 1, 1.
This is a circuit for interlocking the incandescent lamps 2, 2 and the incandescent light bulbs 3, 3, 3, 3 to instruct dimming.

The CPU 5 has an incandescent light bulb 3 in each lamp 1, 1, 1, 1.
It is connected to dimming circuits 6, 6, 6, 6 for adjusting the outputs of 3, 3, 3 to control the dimming circuits 6, 6, 6, 6.

The CPU 5 controls the output of the incandescent light bulb 3 of the lamp whose output tube output is adjusted to the maximum while keeping the output ratio of each incandescent light bulb 3 equal to the output ratio of each discharge tube 2. So that it is automatically adjusted.

FIG. 2 is a diagram showing an operation flowchart of an embodiment of the present invention.

First, start this flowchart, for example, 1/6
The data for each aperture (from voltage to light intensity) is converted (step 1).

Next, each lamp 1, 1, 1, 1 is changed from A to D for convenience, and the maximum value (Y) of these lamps A to D is determined (step 2).

Then, the maximum value (Y) of these lamps A to D is set to Y = 30.
It is obtained from -Xn and is set as the shift amount Y (step 3).

Next, calculation of light amount of each incandescent lamp 3, 3, 3, 3 shown in FIG. 1, X _A = X _A + Y, X _B = X _B + Y, X _C = X _C +
Y, X _D = X _D + Y is performed (step 4).

As described above, one of the outputs of the incandescent lamps 3, 3, 3, 3 is automatically adjusted to the maximum output.

Then, each data of X _{A to} X _D is phase data, and X _A = t
₁ , X _B = t ₂ , X _C = t ₃ , and X _D = t ₄ are converted, and the above-described flowchart ends (step 5).

Next, a specific example in which the light amount is adjusted by the above configuration and operation will be described with reference to FIG.

In this figure, the lamps 1, 1, 1, 1 are, for convenience, 1a, 1
b, 1c, 1d.

In the figure, 21 is a camera, 22 is a subject, and 23 is a back screen.

The discharge tubes 2, 2, 2, 2 of the lamps 1a, 1b, 1c, 1d
Has a maximum output of 1200 W.S.

In this state, the light amount is adjusted while looking at the shadow of the subject 22, and the output of each discharge tube 2, 2, 2, 2 is 150 W.
Set to S, 75W.S, 37.5W.S.

Next, the output of the incandescent lamp 3 of the specific lamp 1 adjusted to the maximum output in each discharge tube 2, 2, 2, 2 at this time is automatically set to the maximum output, that is, the maximum output of the incandescent lamp 3 is 200 W. Adjust to.

At the same time, if the output of other incandescent bulbs is automatically adjusted so that the output ratio of each incandescent bulb is the same as the output ratio of each discharge tube, the output of each incandescent bulb will be as shown in Table 2 below. Become.

Comparing this with Table 1, each incandescent light bulb 3, 3,
The outputs of 3 and 3 are improved as a whole, the subject 22 becomes brighter, and the state of the subject 22 can be visually confirmed.

In the present embodiment, the reference output at the time of adjusting the light amount is the maximum output of the incandescent lamp of the lamp whose discharge tube output is adjusted to the maximum, but may be the maximum output or less, and the number of the lamps, The output value and the like can be changed as appropriate.

(Effect of the invention) As described above, according to the present invention, the output of the reference incandescent lamp is set to a preset large output while the output ratio of the discharge tubes is kept at the same ratio as the output ratio of the incandescent lamps. Since the incandescent lamp is automatically adjusted so that each incandescent lamp can be brightly turned on, it becomes extremely easy to visually confirm the subject.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, FIG. 2 is a diagram showing an operation flowchart of the embodiment of the present invention, and FIG. 3 is a layout diagram of photographing using the same embodiment, FIG. FIG. 4 is a block diagram showing a configuration of a conventional example, and FIG. 5 is a layout diagram of its photographing. In the figure, 1, 1, 1, 1 ... Lamp, 2 ... Discharge tube, 3 ... Incandescent light bulb, 4 ... Light amount determination circuit, 5 ... CPU.

Claims (1)

[Claims] 1. A lighting system in which a plurality of lamps provided with a discharge tube for emitting instantaneous light and an incandescent lamp for emitting constant light are used, and the output of the discharge tube of each lamp is adjusted to illuminate a subject. , Selecting the brightest adjusted discharge tube among the discharge tubes, from the maximum setting output, the data corresponding to the shift amount obtained by calculating the output of the selected discharge tube, for each lamp In addition to the incandescent lamp, the output of the incandescent lamp of the lamp equipped with the brightest discharge tube was automatically adjusted to the maximum at the same time so that the shooting condition could be confirmed with the naked eye and the writing could be done easily. Modeling dimming method of electronic flash that features.