JP2803095B2 - Camera that can shoot trim - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Industrial Field of the Invention The present invention relates to a camera that can perform trim shooting, and more particularly to an improved camera that can set the tuning shutter speed at a higher speed during flash trim shooting.

B.Conventional technology Conventionally, while taking a picture that anticipates the trimming of the print at the time of shooting, information of the trimming ratio is recorded in the margin of the film or in the storage unit attached to the cartridge, and based on the trimming information at the time of printing A system for obtaining a cropped photo is known. With trim shooting, such trimming information is recorded at the time of shooting,
Photographing is a method of obtaining a photograph equivalent to photographing with a zoom lens during printing, and is also called pseudo zoom photographing.

On the other hand, when an electronic flash device is attached to a camera with a focal plane shutter to perform flash photography, it is necessary to make the arc tube emit light while the shutter is fully open.
There are restrictions on the shutter speed that can be used (referred to as a synchronized shutter speed). For this reason, at the time of flash photography, the shutter control circuit limits the shutter speed so as not to be faster than the synchronized shutter speed.

C. Problems to be Solved by the Invention By the way, in the pseudo zoom photographing described above, among the images exposed on one screen of the film at the time of trim photographing, the part printed at the time of printing is a part of the central part of the screen, It is smaller than the screen during normal shooting. For this reason, if the arc tube is made to emit light during flash photography while the shutter fully opens this part of the screen, exposure unevenness due to so-called slit exposure is prevented, and as a result, the synchronized shutter speed is set higher than normal. Can shift to high speed side.

However, conventional cameras capable of performing trim shooting do not consider such a problem at all.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a camera capable of performing trim shooting in which a tuning shutter speed during flash trim shooting is shifted to a higher speed side.

D. Means for Solving the Problems The present invention is applied to a camera with a focal plane shutter capable of performing trim photographing, which records information regarding a change in the angle of view on an information storage medium and performs photographing. At the time of trim shooting with flash emission, a control means for starting the rear curtain at a timing earlier than the rear curtain travel start timing at an earlier time than the rear curtain travel start timing at the time of normal flash photography,
This solves the above problem.

E. Function During trim shooting, the synchronized shutter speed is shifted to a higher speed. Therefore, it is possible to take a picture at a shutter speed higher than in the past, and to provide a camera with a wide range of taking conditions and excellent operability.

F. Embodiment An embodiment of the present invention will be described with reference to FIGS.

In FIG. 1, various command signals are inputted to a discriminating operation circuit 1 from a trimming ratio designation dial 2, an exposure mode selector 3, and a shutter speed setting dial 4.
Assuming that the focal length of the photographic lens attached to the camera is 35 mm, the trimming ratio designation dials 2 are adjusted to 35, 50, 70, and 105, respectively, to obtain the trimming ratios of 1,1.4, 2, and 3, respectively. (Information related to the change of the angle of view) is supplied to the discrimination arithmetic circuit 1. Here, the trimming ratio is, as shown in FIG. 2, a trimming ratio 1, that is, the vertical dimension y of the screen 12a on the film 10 during normal shooting.
_1, the trim print, i.e., the ratio of the vertical dimension y ₂ screens 12b to be subjected to print an area of a portion of the screen 12a on the basis of the trimming information, for example, the trimming ratio 1 y ₁ / y ₂ = 1, trimming ratio 2 represents y ₁ / y ₂ = 2. Then, a finder (not shown) is controlled to a corresponding field of view in conjunction with the selected trimming ratio. When the exposure mode selector 3 is set to P, S, A, or M, respectively, a program automatic exposure, a shutter speed priority type automatic exposure, an aperture wired type automatic exposure, and a manual exposure are selected. Each exposure control is well known, and the description is omitted.

The focal plane shutter 5 has a well-known vertical traveling type front curtain and a rear curtain.
The traveling is controlled by the rear curtain control magnet.
Each curtain control magnet is controlled by a command signal from the shutter control circuit 6. The shutter control circuit 6 always starts running the front curtain of the shutter at a predetermined timing, and the rear curtain at a timing calculated by the discrimination circuit 1. To control the traveling. The sync switch 5a is turned on substantially in synchronization with the opening of the aperture by the front curtain, and an on signal is supplied to the sync circuit 7, and the sync circuit 7 is turned on by the electronic flash device 8.
To supply a light emission start signal to cause the light emitting tube to emit light. The electronic flash device 8 has a main switch 8a. When this switch is turned on, the electronic flash device 8 notifies the discrimination arithmetic circuit 1 that flash photography is being performed.

The recording device 9 records the trimming information on the trimming ratio sent from the discriminant operation circuit 1 in a margin of the film 10 as, for example, a barcode display 11 shown in FIG.
This recording device 9 imprints trimming information by illuminating the margin of the film with a lamp through a liquid crystal pattern or illuminating the film with a light emitting diode, for example. A semiconductor memory may be provided in the cartridge 10a, and trimming information may be recorded therein as code data. Alternatively, film 10 or cartridge 10a
Alternatively, the trimming information may be recorded on a storage medium such as a memory card detachable from the camera. These pieces of trimming information are read in the process of printing the film, and are stretched according to the trimming information to obtain a photograph equivalent to zooming.

 Next, the operation will be described according to the actual shooting procedure.

(I) When the trimming ratio designation dial 2 is set to 35 mm (normal flash photography); the screen provided for printing in this case is the screen 12 shown in FIG.
It is a vertical dimension y ₁ in a. Main switch 8 of electronic flash device 8
When a is turned on, the discrimination arithmetic circuit 1 determines that flash photography is performed at the trimming ratio 1. 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. This front curtain will open in the locus of a curve L ₁ of FIG. 3 (a). FIG. 3 (a) shows a running timing chart of the shutter, in which the horizontal axis represents the elapsed time and the vertical axis represents the screen 12a.
Represents the change of the shutter slit edge in the short side direction. The synchro switch 5a is turned on at the timing of the point P2 after the front curtain has passed the point P1 where the screen 12a ends to open the screen 12a, the synchro circuit 7 is triggered and a light emission start signal is supplied to the electronic flash device 8, and the light emission tube is fired. I do. Emission characteristics showing a luminous energy to the light emitting elapsed time shown by the solid line L ₃ in FIG. 3 (b). When the emission energy exceeds the peak, the rear curtain control magnet is driven by a signal from the shutter control circuit 6. As a result, the trailing curtain is shown in FIG.
Of the curve L2. The emission energy is almost zero before the rear curtain starts closing the screen 12a. Therefore, the light emission of the electronic flash device 8 is completed while the screen 12a is completely open, so that uniform exposure can be performed.

As described above, when the front curtain is driven along the curve L ₁ and the rear curtain is driven as the curve L ₂ , the shutter speed is indicated by X ₁ in FIG. 3A. FIG As can be seen from, moving the rear curtain so the shutter speed is shorter than X ₁ to early (e.g. curve
And L as in _20), the rear curtain While emission does not end the screen 1
2a, which causes exposure unevenness. The shutter speed X ₁ is tuned shutter speed. Therefore, in this embodiment, when the P mode or the A mode is selected by the exposure mode selector 3, the discriminant operation circuit 1 and the shutter speed _1, which are determined according to the brightness of the subject, are set so as not to be shorter than X1.
The shutter speed is controlled by the shutter control circuit 6. on the other hand,
When S mode or M mode is selected, is controlled to be slower shutter speed than the tuning shutter speed by shifting the shutter speed to X ₁ if set faster shutter speed than X ₁ at a shutter speed dial .

In such flash photography, the recording device 9 records the trimming information with the trimming ratio 1 in the margin of the film 10 as a bar code display 11 as shown in FIG. 2, for example.
If the trimming ratio is 1, nothing may be recorded. The above photographing is the normal flash photographing.

(II) When the trimming ratio designation dial 2 is set to 70 mm (flash trim shooting); the trimming ratio in this case is 2, and the screen used for trim printing is indicated by reference numeral 12b in FIG. with respect to the longitudinal dimension y ₁ of a longitudinal dimension _{y 2 (= y 1/2} ). In this case, as shown by curve L ₂₀ of FIG. 3 (a), as the travel of the rear curtain is started at a faster time than the time indicated by the curve L ₂ in the trimming ratio 1, curtain rear shutter control circuit 6 Control the control magnet. That is, when the trailing curtain starts covering the screen area 12b to be subjected to the trim print, the timing of the start of the trailing curtain is advanced to such an extent that the light emission is almost completed, thereby setting the shutter speed to X ₁ when the trimming ratio is _1. Faster than X ₂ (<X ₁ ).

Thus, the 70mm photography as a trimming ratio 2, limits P, and tuning shutter speed in the A both modes at X _2,
S, in M both modes, the shutter control circuit 6 so as to forcibly shifted in X ₂ and fast shutter speed is set than X ₂ limits the shutter speed.

At the time of this photographing, the 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 the flash trim shooting.

When printing the flash-trimmed film as described above, the trimming ratio 2
Reading trimming information of the screen vertical dimension if only the printing area 12b is y _2, no zooming photographic the exposure unevenness is obtained.

Even if the specified dial 2 was set to the trimming ratio 1.4,3 in the 50,105, when similarly flash photographing trimming ratio 1 and described above faster tuning shutter speed X ₂ than the tuning shutter speed X ₁ of the (normal flash photography) Are set according to the respective trimming ratios. More trimming ratio greater tuning shutter speed X ₂ is faster of course to be set.

In the above description, when the P and A modes are selected by the exposure mode selector 3, the shutter speeds lower than the synchronized shutter speeds X ₁ and X ₂ at each trimming ratio can be freely used, but from the viewpoint of preventing camera shake. the shutter speed may be fixed to the X ₁ or X _2.

Although the vertical traveling shutter was used, the horizontal dimension of the screen becomes shorter in accordance with the trimming ratio even with the lateral traveling shutter.
The tuning shutter speed at the time of trim shooting is changed according to the trimming ratio as compared with the normal flash shooting, whereby the tuning shutter speed at the time of trim shooting can be increased.

Furthermore, in determining the tuning shutter speeds X ₁ and X ₂ , the rear curtain starts closing the screen provided for printing after the emission energy of the arc tube has disappeared. Just start closing the screen inside. Furthermore, the electronic flash device 8 may be either an external type or a built-in type. In the external type, the synchronizing circuit 7 may be provided on either the electronic flash device side or the camera side.

G. Effects of the Invention According to the present invention, the rear curtain start time is advanced and the synchronized shutter speed can be shifted to the high speed side during flash trim shooting in which the trimming ratio is greater than 1 as compared with normal flash shooting with a trimming ratio of 1. For this reason, daytime synchro photography can be performed on a higher luminance side. In addition, the influence of light other than the electronic flash device can be eliminated, that is, photographing mainly using the light of the flash device can be performed, and the original color of the light emitted from the flash device can be obtained, so that a photograph having a preferable color tone can be obtained. Further, the degree of freedom of the combination of the aperture value and the shutter speed is expanded, and it is possible to respond to a wider photographing intention.

[Brief description of the drawings]

1 to 3 illustrate an embodiment, FIG. 1 is a block diagram showing the overall configuration, and FIG. 2 shows screens on a film provided for printing during normal shooting and trim shooting, respectively. FIG. 3 is a diagram illustrating characteristics of a shutter travel locus and light emission energy. 1: Judgment operation circuit 2: Trimming ratio designation dial 3: Exposure mode selector 4: Shutter speed setting dial 5: Focal plane shutter 5a: Synchro contact, 6: Shutter control circuit 7: Synchro circuit, 8: Electronic flash device 9: Recording Equipment, 10: Film

Claims (1)

(57) [Claims] 1. A trim-equipped camera with a focal plane shutter capable of recording information relating to a change in the angle of view on an information storage medium and performing photographing. A trim-capable camera equipped with a control means for starting the rear curtain at a timing earlier than the timing.