JPH0232324A - Camera capable of trim photographing - Google Patents

Abstract

PURPOSE:To constitute the title camera so that the maximum shutter speed at the time of flash trim photographing can be shifted to a high speed side by providing a control means for outputting a rear curtain running start command at an earlier time than a rear curtain running start timing at the time of regular flash photographing by interlocking with trim photographing. CONSTITUTION:A focal-plane shutter 5 has a front curtain and a rear curtain of a longitudinal running type, and its running is controlled by a front curtain control use magnet and a rear curtain control use magnet, respectively. Each curtain control use magnet is controlled by a command signal from a shutter control circuit 6, and this shutter control circuit 6 controls running of each curtain by the timing corresponding to a shutter speed which is calculated by a discriminative arithmetic circuit 1. In such a case, at the time of flash trim photographing whose trimming ratio is larger than '1', comparing with regular flash photographing whose trimming ratio is '1', a rear curtain running start time is quickened and a tuning shutter speed can be shifted to a high speed side. Accordingly, a fill-in flash can be executed on the higher luminance side, photographing by other light than an electronic flash device can be eliminated and a photograph of a desirable color tone is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a camera capable of trim photography, and is improved so that the maximum shutter speed can be set to a higher speed especially when flash trim photography is performed.

B. Conventional technology Traditionally, when taking pictures, the cropping of the print is predicted and information on the trimming ratio is recorded in the margin of the film or in the memory attached to the cartridge, and the trimming information is based on that information when printing. A system for obtaining a cropped photograph is known. Trim photography refers to photography in which such trimming information is recorded at the time of photography and a photograph equivalent to that taken with a zoom lens is obtained when printing, and is also called pseudo-zoom photography.

On the other hand, when taking flash photography by attaching an electronic flash device to a camera with a focal plane shutter, it is necessary to cause the arc tube to emit light while the shutter is fully open. There are restrictions on Therefore, during flash photography, the shutter control port C6 prevents the shutter speed from becoming faster than the synchronized shutter speed.The problem to be solved by the invention is to prevent the shutter speed from becoming faster than the synchronized shutter speed. Of the images exposed to light, only a portion of the center of the screen is printed during printing, which is narrower than both sides of the screen when normally photographed. For this reason, if you fire the light from the arc tube while the shutter is fully open for a portion of the screen during flash photography, uneven exposure due to so-called split exposure can be prevented. You can shift 1- to the high speed side.

However, conventional cameras capable of taking trim shots do not take this into consideration at all.

SUMMARY OF THE INVENTION An object of the present invention is to provide a camera capable of trim photography in which the maximum shutter speed during flash trim photography is shifted to a higher speed side.

Means for Solving the D0 Problem The present invention is applied to a camera equipped with a focal plane shutter capable of trim shooting, which records trimming information on a trimming information storage medium to take an image. The apparatus includes a control means for outputting a trailing curtain running start command at a timing earlier than the trailing curtain running start timing during flash photography.

During the 20 action trim photography, the synchronized shutter speed is shifted to a higher speed side. Therefore, it is possible to take pictures at a higher shutter speed than in the past, and a camera with improved operability is provided with a wider range of shooting conditions.

F. Example An embodiment of the present invention will be explained with reference to FIGS. 1 to 3.

In FIG. 1, various command signals are input to a discrimination calculation circuit 1 from a trimming ratio designation dial 2, an exposure mode selector 3, and a shutter speed setting dial 4. If the focal length of the photographic lens attached to the camera is 35 mm, the trimming ratio designation dial 2 should be set to 35.50, 70.
, 105, respectively, it becomes 1, 1.4, 2, respectively.
．． A trimming ratio of 3 is obtained, and this trimming information is supplied to the discrimination calculation circuit 1. Here, the trimming ratio is
As shown in FIG. 2, the trimming ratio is 1, that is, the vertical dimension y of the screen 12a on the film 10 during normal shooting, and the trim print, that is, printing a part of the screen 12a based on the trimming information. For example, trimming ratio 1 is y/y2=1, and trimming ratio 2 is 9□/y2.
y z ” 2.The finder (not shown) is controlled to the corresponding field of view in conjunction with the selected trimming ratio.The exposure mode selector 3 is set to P, S, A, M.
When set to , program automatic exposure, shutter speed priority automatic exposure, aperture priority automatic exposure, and manual exposure are selected respectively. Each exposure control is well known and will not be described further.

The focal plane shutter 5 has a well-known longitudinally running front curtain and a rear curtain, and the running thereof is controlled by a front curtain control magnet and a rear curtain control magnet, respectively. Each curtain control magnet is controlled by a command signal from a shutter control circuit 6, and this shutter control circuit 6 controls the running of each curtain at a timing corresponding to the shutter speed calculated by the discrimination calculation circuit 1. The synchro switch 5a is turned on substantially in synchronization with the front curtain fully opening the aperture, and the on signal is supplied to the synchro circuit 7, which supplies a light emission start signal to the electronic flash device 8 and starts the arc tube. to emit light. The electronic flash device 8 is the main switch 8
a, and when this switch is on, it notifies the discrimination calculation circuit 1 that flash photography is being performed.

The recording device 9 records the trimming information regarding the trimming ratio sent from the discrimination calculation circuit 1 on the margin of the film 10 as a barcode display 11 shown in FIG. 2, for example. This recording device 9 imprints trimming information by, for example, illuminating the margin of the film with a lamp through a liquid crystal pattern, or by illuminating the film with a light emitting diode. A semiconductor memory may be provided in the cartridge 10a, and the trimming information may be recorded therein as code data. Alternatively, the trimming information may be recorded on a storage medium other than the film 10 or the cartridge 10a, such as a memory card that is removable from the camera. This cropping information is read during the process of printing the film, and the image is expanded according to the cropping information to obtain a photograph equivalent to a zoomed photograph.

Next, the operation will be explained according to the actual photographing procedure.

(I) When the trimming ratio designation dial 2 is set to 35 mm (normal flash photography); In this case, the screen used for printing is screen 12 in Figure 2.
The vertical dimension is y at a. When the main switch 8a of the electronic flash device 8 is turned on, the discrimination calculation circuit 1 sets the trimming ratio to 1.
This is determined to be a flash photography. When the camera is released, the discrimination calculation circuit 1 calculates the shutter speed, and the shutter control circuit 6 drives the front curtain control magnet at a predetermined timing. As a result, the leading curtain opens along the trajectory of the curved line L shown in FIG. 3(a). FIG. 3(a) shows a shutter running timing chart, in which the horizontal axis represents elapsed time and the vertical axis represents changes in the shutter slit edge in the short side direction of both surfaces 12a. Point P1 where the front curtain finishes opening the screen 12a
The synchro switch 5a is turned on at the timing of point P2 after passing through, the synchro circuit 7 is triggered, a light emission start signal is supplied to the electronic flash device 8, and the arc tube emits light. The light emission characteristic showing the light emission energy with respect to the elapsed time of light emission is shown by the solid line in FIG. 3(b).

When the emitted light energy exceeds its peak, the trailing curtain control magnet is driven by a signal from the shutter control circuit 6. As a result, the trailing curtain closes along the trajectory of the curve L2 in FIG. 3(a). Before the rear curtain begins to close the screen 12a, the emitted light energy is completely zero. Therefore, screen 1
Uniform exposure is made possible by finishing light emission from the electronic flash device 8 while the electronic flash device 2a is completely open.

As described above, when the front curtain is run along the curve L1 and the rear curtain is run along the curve L2, the shutter speed is indicated by X in FIG. 3(a). As you can see from this figure, the shutter speed is
If the trailing curtain is moved early so that it is shorter than the curve L2° (for example, as shown in curve L2°), the trailing curtain will cover the screen 12a before the light emission ends, resulting in uneven exposure.

This shutter speed X is the synchronized shutter speed. Therefore, in this embodiment, when P mode or A mode is selected by the exposure mode selector 3, the determination calculation circuit 1. A shutter control circuit 6 controls the shutter speed. On the other hand, when S mode or M mode is selected, if a shutter speed faster than X mode is set on the shutter speed dial, the shutter speed is shifted to Xl and the shutter speed is controlled below the synchronized shutter speed.

During such flash photography, trimming information with a trimming ratio of 1 is recorded by the recording device W9 in the margin of the film 10, for example, as a bar code display 11 as shown in FIG. If the trimming ratio is 1, nothing may be recorded. The above photography is normal flash photography.

(■) When the trimming ratio designation dial 2 is set to 70 mm (flash trim photography); In this case, the trimming ratio is 2, and the screen used for trim printing is shown as 12b in FIG. 2, and the screen 12
The vertical dimension is y2 ("y1/2) for the vertical dimension y of a. In this case, as shown by the curve L2° in FIG. The shutter control circuit 6 controls the trailing curtain control magnet so that the trailing curtain starts running at a quick point in time.In other words, the light emission is completely completed at the time when the trailing curtain starts covering the double-sided area 12b used for trim printing. The timing at which the trailing curtain starts running is advanced to the extent that the trimming ratio ends, thereby making it possible to set the shutter speed to XZ (<xt), which is faster than the shutter speed X when the trimming ratio is 1.

Therefore, in 70+nm photography with a trimming ratio of 2, the maximum shutter speed in both P and A modes is limited by X2, and in both S and M modes, if a shutter speed faster than X2 is set, X2 is forced. The shutter control circuit 6 limits the shutter speed so that the shutter speed is shifted to .

Note that during this photographing, a barcode display 11 indicating the trimming ratio 2 is imprinted on the margin of the film 10 by the recording device 9. The above is flash trim photography.

When printing film that has been shot with flash trim as described above, from the barcode display 11 to the trimming ratio 2.
After reading the trimming information, the double-sided vertical dimension is y2.
By printing only the area 12b, a zoomed photograph without uneven exposure can be obtained.

Set the designated dial 2 to 50,105 and the trimming ratio is 1.
Even when set to 4.3, the synchronized shutter speed Ru. Needless to say, the larger the trimming ratio, the faster the set synchronized shutter speed X2.

In the above description, when P or A mode is selected with the exposure mode selector 3, the synchronized shutter speed X1. Although a shutter speed slower than X2 can be freely used, the shutter speed may be fixed to X□ or X2 from the viewpoint of preventing camera shake.

Also, although we used a vertical shutter, even with a horizontal shutter, the horizontal dimensions on both sides become shorter depending on the trimming ratio, so compared to normal flash photography, the synchronized shutter speed during trim photography is changed according to the trimming ratio. This makes it possible to increase the synchronized shutter speed during trim photography.

Furthermore, when determining the synchronized shutter speeds The screen may start closing at the same time. Furthermore, the electronic flash device 8 may be either externally attached or built-in.

In the external formula, synchro circuit 7 is on the electronic flash device side.

It may be provided on either side of the camera.

G0 Effects of the Invention According to the present invention, compared to normal flash photography with a trimming ratio of 1, during flash trim photography where the trimming ratio is greater than 1, the trailing curtain travel start time is earlier and the synchronized shutter speed can be shifted to a higher speed side. Therefore, daytime synchronized photography is possible at higher brightness levels, and the influence of light from sources other than the electronic flash device can be eliminated, resulting in photographs with desirable color tones. Also,
The degree of freedom in combinations of aperture value and shutter speed is expanded, making it possible to respond to a wider range of photographic intentions.

[Brief explanation of the drawing]

Figures 1 to 3 are for explaining one embodiment. Figure 1 is a block diagram showing the overall configuration, and Figure 2 shows the screen on the film used for printing during normal shooting and trim shooting, respectively. The explanatory diagram, FIG. 3, is a diagram showing the characteristics of the shutter travel locus and the light emission energy. 1: Discrimination calculation circuit 2 Drimming ratio designation dial 3: N output mode selector 4: Shutter speed setting dial 5: Focal plane shutter 5a mini synchro point 6: Shutter control circuit 7: Synchro circuit 8: Electronic flash device 9: Recording device @ 10
: Film Figure 2 Patent Applicant Nikon Co., Ltd. Patent Attorney Fuyuki Nagai Figure 3

Claims (1)

[Scope of Claims] In a camera equipped with a focal plane shutter capable of trim photography, which records trimming information on a trimming information storage medium and performs photography, in conjunction with the trim photography, the trailing curtain travel start timing during normal flash photography is provided. A camera capable of trim shooting, characterized in that it is equipped with a control means that outputs a command to start trailing curtain travel at a time earlier than that of the camera.