JPH06180465A - Camera capable of varying aspect ratio - Google Patents

Abstract

PURPOSE:To obtain a printed photograph with high image quality even when enlarging magnification is increased in accordance with the switching of an aspect ratio. CONSTITUTION:A desired frame is selected by operating an operation lever 8. Based on a signal from a frame switch 8a, a program by which an allowable circle of confusion can be given to the printed photograph according to the size of the selected frame is selected from a program ROM 33. Since the sensitivity of a film is inputted to a CPU 10 from a DX code reading part 34 and photometry data is inputted to the CPU 10 from a photodetector 30, a program shutter 48 is driven based on the data and the AE program.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable aspect-ratio camera for designating an aspect ratio of a print photograph.

[0002]

2. Description of the Related Art Among recent 35 mm full size compact cameras, like the "Cardia Travel Mini" (trade name) sold by the applicant, it is possible to take pictures with a screen size that can receive a panoramic print service. There is something like this. In such a camera, the exposure range "24 mm x 36 mm" which is usually equivalent to 35 mm full size
Although the image is taken at (aspect ratio 1.5), when the intended panorama print is intended, the mask plates that regulate the exposure range are inserted above and below the aperture, and "13 mm x 36 mm" is displayed.
It is possible to shoot in a horizontally long exposure range (aspect ratio of about 2.8). Then, the negative photographed at this size is enlarged and printed at about twice the normal service print at the time of printing to make a landscape panorama print.

In a camera having such a function, a frame is displayed on the viewfinder so that the range to be printed can be known at the time of shooting. Therefore, if the setting information is recorded magnetically or optically on the film corresponding to such a frame display and this information is read at the time of printing, the mask plate can be omitted and the photographing screen itself. Even if the size is "24 mm x 36 mm", the same panoramic print photograph can be obtained by trimming so as to leave a range of "13 mm x 36 mm" and performing enlargement printing.

Recently, in addition to normal print and panoramic print, for example, HDTV size print (aspect ratio of about 1.8) and cinemascope size print (aspect ratio of about 2.3) have different aspect ratios. A camera having an aspect ratio designation function for designating several kinds of print sizes has been proposed.

[0005]

By the way, when the aspect ratio is changed by the above camera and, for example, panoramic photography is performed, the exposure area on the negative is about 1/2,
Moreover, since the size of the print photograph is about 2 times, the enlargement ratio is about 4 times. Therefore, as compared with a photograph printed from a full size of 35 mm, the out-of-focus portion is enlarged and the image quality of the entire screen is deteriorated.

The present invention has been made in view of the above circumstances, and provides a variable aspect ratio camera that prevents deterioration in image quality of a print photograph due to an increase in enlargement magnification accompanying switching of the aspect ratio.

[0007]

In order to achieve the above object, in the aspect ratio variable camera according to claim 1, a permissible circle of confusion corresponding to the enlargement magnification which changes with the switching of the aspect ratio is given to the print photograph. Further, it is provided with aperture value changing means for changing the photographing aperture, and shutter speed changing means for changing the shutter speed so that the subject is properly exposed corresponding to the photographing diaphragm. Also,
The variable aspect ratio camera according to claim 2 changes the program of the automatic exposure means in conjunction with the operation of switching the aspect ratio, and prints a permissible circle of confusion corresponding to the enlargement magnification changed with the switching of the aspect ratio. It was designed to be given to. As a result, the out-of-focus range is reduced, and a high-quality printed photograph can be obtained even if the enlargement ratio is increased.

[0008]

EXAMPLE FIG. 2 showing the appearance of an example of the present invention,
A zoom lens 2 is provided in the center of the front surface of the camera body 1, a photometric window 3 is provided above it, a viewfinder 4 is provided above it, distance measuring windows 5a and 5b are provided at the upper left portion, and upper right portions are provided. A strobe light emitting section 6 is provided. Further, a shutter release button 7 and a slide type operation lever 8 for switching the aspect ratio are provided on the upper surface of the camera body 2. Further, a zoom lever 9 for switching the focal length of the taking lens 2 is provided on the back surface.

The frames that can be switched by the operating lever 8 are L, H, C and P shown in Table 1 below.
It is a kind.

[0010]

[Table 1]

High-definition is a high-definition television, and it is advantageous that an image shot on this size screen does not need to be trimmed when it is converted into an electronic image such as an electronic still image.

FIG. 1 schematically shows the electrical construction of the camera. The operation of the camera is controlled by the CPU 10, and operation signals for half-pressing and full-pressing the release button 7 are input via the release switch 7a. The movement of the operation lever 8 and the zoom lever 9 is performed by the frame switch 8a,
It is detected by the zoom switch 9a. The zoom motor 13 is driven via the motor driver 12 by the signal from the zoom switch 9a, and the zoom lens 2 and the finder optical system 14 are zoomed.

Behind the photometric window 3 is a light receiving element 3 for photometry.
0 is placed. The metering window 3 has a deep depth of field,
For example, it is a lens of about F11 or F16, and the subject light incident from the photometric window 3 is always imaged on the light receiving element 30 regardless of the distance of the subject. As the light receiving element 30, for example, SPD (silicon photodiode) is used. The output from the light receiving element 30 is logarithmically compressed by the logarithmic compression amplifier 31, and then the A / D converter 3
It is A / D converted by 2 and input to the CPU 10.

When the frame type is selected by the frame switch 8a, the CPU 10 causes the program ROM 3 to operate.
Select a predetermined program diagram from 3. Program R
As shown in FIG. 3, there are three types of program diagrams stored in the OM 33, which are indicated by reference numerals A, B, and C. The program diagrams A, B and C are as shown in Table 2 below.
Based on the enlargement magnification ratio of each frame, it is determined that the permissible circle of confusion required for each print photograph can be obtained. Further, the open F value of the frame size corresponding to each of the permissible circles of confusion is the open F value of 35 mm full size being 3.
When it is set to 5, it becomes as shown in Table 2.

[0015]

[Table 2]

Here, the relationship among the enlargement magnification, the permissible circle of confusion, the depth of focus, and the F value will be briefly described. When making a print photo from each of the L, H, C, and P screen sizes shown in Table 1, if you decide to use paper of the same width as the paper currently used in full size and panorama size, The size enlargement ratio depends on the size of the paper in the longitudinal direction (horizontal size). The enlargement ratio of each size is 35mm compared to the full size.
As shown in Table 2, the reciprocal thereof is the ratio of the diameter of the circle of confusion on the film surface to obtain an image quality (circle of confusion on the printed surface) equivalent to 35 mm full size (vs. full size).

In FIG. 4, a: Allowable circle of confusion in the case of 35 mm full size Fa: Open F value Da: Depth of focus determined from Fa and a b (= c): Allowable circle of confusion when the enlargement magnification is large Db: Camera Depth of focus when the permissible circle of confusion is b with an open F value of F F: F value that satisfies the permissible circle of confusion c with the same depth of focus Fc: Da. Is the expression. (Focal depth) = (F value) × (allowable circle of confusion) (1) That is, in order to satisfy a certain allowable circle of confusion (b = c), the focus depth is set to Db without changing the F value. Alternatively, the F value may be set to Fc without changing the depth of focus. However, when the depth of focus is made shallow, the focusing accuracy may be practically insufficient due to problems such as the set point of autofocus. Even if there is no problem in focusing accuracy, a deeper depth of focus is desirable considering that most of the objects are three-dimensional objects. Therefore, in this embodiment,
The exposure control is performed according to the program diagram (see FIG. 3) in which the aperture and the shutter speed are combined so that the F value, that is, the aperture value, increases when the enlargement magnification increases. In addition, the sensitivity of the used film required for exposure control is captured D
The X code reading unit 34 is connected to the CPU 10.

When the CPU 10 receives the signal from the frame switch 8a, it drives the LCD driver 15 and operates the liquid crystal display plate 16 provided in the finder optical system 14. The finder optical system 14 is, for example, a Kepler-type real image finder, as shown in FIG.
A liquid crystal display plate 16 showing a field frame is provided on the incident surface side of a Porro prism 14c provided between the objective lens 14a and the eyepiece lens 14b. Further, reference numeral 1 shown in FIG.
Reference numeral 7 denotes an autofocus device, which is actuated by half-pressing the release button 7 to input a distance measurement signal to the CPU 10.

The liquid crystal display panel 16 includes segments 20, 2
1, 22, 23, and 24. These segments are transparent and opaque in the combinations shown in the table below in conjunction with the switching of frames.

[0020]

[Table 3]

The CPU 10 also includes an exposure frame switching device 3
8 is connected, and when the shutter release button 7 is pressed halfway after switching the field of view frame, as shown in FIG.
The exposure frame switching device 38 operates, and the exposure opening 40 switches to each screen size. The exposure frame 41 includes a pair of upper and lower side masks 42 and 43 which are movable in parallel with each other.
It is composed of a pair of left and right side masks 44 and 45. The upper and lower side masks 42, 43 have one end fixed to the endless belt 46, and move in the up and down direction by the rotation of the stepping motor 47 so as to approach or separate from each other. The left and right side masks 44 and 45 are also configured in the same manner, and approach or separate from each other in the left and right direction by a stepping motor (not shown).

As a result, L is 21.2 mm × 31 m
The opening size is m, and H is 21.2 mm x 37.7.
mm, C: 16.4 mm x 37.7 mm, P: 1
The opening size is 3.2 mm × 37.7 mm. In addition,
In addition to the movement of the masks 42 to 45 by the belt and the stepping motor, these masks may be moved in parallel by a solenoid, a link device, a rack and a pinion, or the like.

The operation of the camera thus configured will be described. When the camera is loaded with the film, the DX code provided on the surface of the cartridge is read by the DX code reading unit 34.
And the film sensitivity is input to the CPU 10. When the operation lever 8 is adjusted to, for example, the index L, the corresponding segments 22, 23, 24 of the liquid crystal display plate 16 become opaque and the photographing area can be confirmed by the viewfinder 4. At the same time, the CPU 10 causes the program ROM 3
Select program diagram A from 3.

The user operates the shutter button 7 after confirming the zooming by zooming and the frame size of L preset by the user with the finder 4. When the shutter button 7 is pressed halfway down, the autofocus device 17 operates to focus the zoom lens 2, and at the same time, photometry is performed in a region corresponding to the type of frame selected in advance, that is, L. Is input to the CPU 10. Further, the exposure frame switching device 38 is activated to operate the exposure opening 4
0 is set to 35 mm full size.

When zooming by zooming and the frame size of L are confirmed by the viewfinder 4, and the release button 7 is fully pressed, the diaphragm and shutter speed are determined based on the film sensitivity, photometric data and program diagram A. A known program shutter 48 is driven by. At this time, if the subject brightness is low enough to cause a slow shutter, the strobe light emitting section 6 automatically emits strobe light toward the subject at the same time as the release button 7 is fully pressed. When the shooting is completed, the motor 19 is driven to feed one frame of film.

When all the frames are photographed by repeating the above operation, the film is rewound into the cartridge. The Patrone is taken out of the camera and then submitted to the DPE store. After the film has been developed, it is applied to an automatic printer. Since each frame of the film is exposed within a range corresponding to the type of frame, L, H, C, and P, this is automatically detected. As a result, the negative mask or the paper mask is moved, the print magnification is determined, and the print photograph having the aspect ratio selected by the photographer can be obtained.

As described above, the open F value, which is the setting factor of the exposure program corresponding to each frame size, is 3
Determined by the stretch ratio of the full size of 5 mm. In this embodiment, since the frame switching size is limited to four types, the enlargement magnification ratio with the 35 mm full size can be calculated in advance, and thereby each open F value can also be determined in advance. Therefore, each exposure program is recorded in the table memory, and the corresponding exposure program is selected from the table memory in conjunction with the switching of the frame size. However, the present invention is not limited to this, and each time the enlargement ratio at the time of printing is calculated based on the switched aspect ratio, thereby obtaining the enlargement ratio of 35 mm full size, and based on this, An open F value that gives a circle of confusion may be calculated.

Further, in the embodiment described above, the multi-program system in which one program corresponding to the selected aspect ratio is selected from a plurality of programs prepared in advance and the program shutter is driven is used. However, the shutter speed may be calculated corresponding to the diaphragm corresponding to the selected aspect ratio, and exposure may be performed at this diaphragm and shutter speed.

In the above embodiment, the exposure frame switching device 38 is used to switch the screen size for shooting, but in addition to this, all shooting is performed with one screen size and the trimming indicating the screen size is performed. The information may be recorded in the magnetic recording layer of the film, the IC memory of the cartridge, or the like, and the pseudo trimming photographing may be performed. In this case, the trimming information is read at the time of printing, and trimming printing is performed based on this. In addition, the present invention is not limited to the numerical value of the aspect ratio and the number of screens. Further, as described above, if the enlargement ratio is set while keeping the width size of the print photograph constant, it is possible to minimize the complexity of the print processing that occurs with the increase in the type of aspect ratio.

[0030]

As described above, according to the aspect ratio variable camera of the present invention, the permissible circle of confusion corresponding to the enlargement magnification changed in association with the aspect ratio switching operation is given to the print photograph. As a result, out-of-focus enhancement is eliminated, and even if the enlargement ratio is increased, it is possible to obtain a printed photograph with high image quality.

[Brief description of drawings]

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

FIG. 2 is a perspective view showing an appearance of a camera.

FIG. 3 is a program diagram according to the present invention.

FIG. 4 is an explanatory diagram showing a relationship between an allowable circle of confusion, a depth of focus, and an F value.

FIG. 5 is a perspective view showing a structure of a finder.

FIG. 6 is a perspective view showing a main part of an exposure frame switching device.

[Explanation of symbols]

 8 Operation lever 8a Frame switch 10 CPU 33 Program ROM

Claims (2)

[Claims] 1. In a variable aspect ratio camera equipped with an aspect ratio designating means for designating an aspect ratio of a trimming range at the time of printing, a permissible circle of confusion corresponding to an enlargement magnification which changes with switching of the aspect ratio is given to a print photograph. Variable aperture ratio changing means for changing the photographing aperture so that the subject has a proper exposure corresponding to the photographing diaphragm, and a shutter speed changing means for changing the shutter speed so that the subject has an appropriate exposure. camera. 2. A photometric means for photometrically measuring a subject brightness for determining an exposure amount of a film, an aspect ratio designating means for designating an aspect ratio of a trimming range at the time of printing, and a photometric data from the photometric means. In a variable aspect ratio camera equipped with a program type automatic exposure unit that automatically determines the combination of aperture and shutter speed, the program of the automatic exposure unit is changed in conjunction with the aspect ratio switching operation, and the aspect ratio is switched. A variable-aspect-ratio camera characterized in that a permissible circle of confusion corresponding to the enlargement magnification changed in accordance with the above is given to a print photograph.