JP2690954B2 - camera - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a camera that warns of a shooting failure.

[Conventional technology]

Generally, a camera measures the brightness of a subject before photographing, calculates an exposure value based on the brightness, and controls the aperture value according to the exposure value at the shutter speed. Then, if the exposure value calculated before shooting is outside the exposure range that can be taken by the camera, there is a camera that warns whether the exposure is likely to be over-exposure or under-exposure. Further, when the brightness of the subject is dark and the shutter speed is likely to be long, there is a high possibility of camera shake, and therefore some cameras warn the user to be careful of camera shake.

[Problems to be solved by the invention]

The most disturbing thing about taking a picture is that I don't know if I was able to take the picture correctly until I developed the film.

The conventional camera described above only issues a warning based on the state immediately before shooting, and does not give a warning regarding how the actual shooting was performed. Therefore, if the camera has some kind of failure, it will be a big failure. One of the biggest mistakes I make in photography is that I don't see the photo that I thought I had taken. In particular, no action can be taken when it is not exposed at all.

The present invention has been made to cope with the above-described circumstances, and its purpose is not to give a warning about a shooting result predicted from a state before shooting, but to judge during shooting whether the shooting operation has been performed correctly. It is to provide a camera that issues a warning immediately after shooting when the shooting operation is not performed correctly.

Another object of the present invention is to provide a camera that determines whether or not the actual exposure amount on the film surface is within a permissible range determined according to film sensitivity with respect to a predetermined exposure value. Is.

[Means for solving the problem]

The camera of the present invention comprises means for calculating an appropriate exposure amount on the film surface based on subject brightness and sensitivity of the film loaded, means for measuring the exposure amount on the film surface during exposure, and the appropriate exposure value. The first comparing means for comparing the amount of light and the measured exposure amount after exposure and outputting a judgment signal if the difference between the two is not within a predetermined allowable range; and a first for displaying information according to the judgment signal. Second display means, means for measuring the camera shake amount during exposure, the measured shake amount and a predetermined value are compared after the exposure, and a second comparison signal is output if the measured shake amount is equal to or greater than the predetermined value. Means and second display means different from the first display means for outputting information according to the determination signal are provided. Further, the predetermined allowable range is different depending on the film sensitivity.

[Action]

According to the present invention, when taking a photograph according to the proper exposure amount calculated in advance, the actual exposure amount to the film surface is measured during the exposure, and the difference between the measured value and the proper exposure amount is within the allowable range. If not, a warning will be issued and
By measuring the shake amount applied to the camera during exposure, and when the measured value is equal to or larger than a predetermined value, a warning can be issued to know immediately after the shooting whether or not the shooting was actually performed appropriately.

Further, according to the present invention, by setting the allowable range according to the film sensitivity, it is possible to more accurately determine whether or not an appropriate exposure amount is actually given to the film.

〔Example〕

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

 FIG. 1 is a perspective view of the first embodiment as viewed from the front.

On the front side, a photographing lens 1, a finder objective lens 2,
Auto-focus (AF) LED projection lens 3, AF LED
The light receiving lens 4 and the strobe 6 are provided. Part of the taking lens 1 is a light receiving lens 5 for measuring the brightness of the subject.
Is provided.

An LCD panel 7 serving as an external display unit and a release button 8 are provided on the upper surface.

FIG. 2 is a perspective view of the first embodiment as seen from the back side, and is a view in a state where the back cover 9 is open.

A cartridge chamber 10 is provided on the left side, and a pin 11 for detecting the presence or absence of a cartridge (film cartridge) is projected in the cartridge chamber 10. The pin 11 is retracted when the cartridge is inserted, and the presence or absence of the cartridge can be detected by changing the protruding state of the pin 11 into an electric signal by a switch (not shown).

A finder eyepiece lens 12 is provided on the back surface. A film feeding check gear 13 is provided in the film feeding path between the cartridge chamber 10 and the winding spool 15.
The gear 13 is rotated by the perforation hole of the film, and every time the gear 13 feeds eight teeth, an electric signal indicating that one film has been fed is generated. This makes it possible to check whether the film is fed correctly.

A photometric element for measuring the reflected light from the film surface is arranged in the dark box, and a light receiving lens 14 is provided on the front surface thereof.
A compact and lightweight semiconductor acceleration sensor that detects horizontal and vertical accelerations and detects the amount of shake applied to the camera.
16,17 are built into the main body.

 FIG. 3 is a sectional view of the first embodiment.

A light-receiving lens 14 for measuring reflected light (exposure amount on the film surface) from the film surface 18 and a photometric element 14 'such as a photodiode are provided at the bottom of the camera. Light receiving lens 5
After that, a photometric element 5'for photometrically measuring the brightness of the subject is provided to determine the exposure value. At the position of the diaphragm of the taking lens 1, a normally-closed vario type shutter 19 is arranged.

 FIG. 4 is a display example of the LCD panel 7 above the camera.

Mark 20 indicates the number of shots. Mark 21,22,23
Is a display unit for a warning when the shooting is not performed correctly. When the shooting was not done correctly, these marks 2
1,22,23 blinks. The mark 21 indicates that the film was not fed correctly, the mark 22 indicates that the exposure amount on the film surface was not correct, that is, when the exposure was over or under, and the mark 23 indicates that the shutter was operating. When the amount of shake applied to the camera during the period is larger than a certain amount, each flashes to warn.

 FIG. 5 is a display example of the display section in the finder.

An AF target frame 25 is provided in the center of the field frame 24, and under the field frame 24, an OK mark indicating that the shooting was correctly performed and a green LED 26 are on the left side, indicating that the shooting was not performed correctly. The NG mark shown and the red LED 27 are provided on the right side. After shooting, one of the LEDs 26 and 27 lights for a certain period of time.

 FIG. 6 is a block diagram of the entire electric circuit of the camera.

The sequence switch group 28 includes a release switch,
Detects sequence information for the entire camera. The cartridge presence / absence monitor 29 detects the presence / absence of a cartridge based on the protruding state of the pin 11. The film feed monitor 30 counts the signals from the gear 13. The film surface exposure amount monitor 31 integrates the output of the photometric element 14 'during photographing to monitor the exposure amount that actually reaches the film surface. The AE photometric circuit 32 uses the output of the photometric element 5'to meter the brightness of the subject before exposure. The camera shake amount monitor 33 is a semiconductor acceleration sensor 16, 17
The output of is used to monitor the camera shake amount during shooting. The autofocus control circuit 34 performs distance measurement using an AE sensor and controls the lens position based on this distance measurement information. The exposure control circuit 35 controls the shutter aperture and shutter speed based on the output of the AE photometry circuit 32. The winding control circuit 36 controls the information of the sequence switch group 28 and the film feeding monitor 30.
The film winding motor is controlled using the information of. LCD
The display unit 37 drives the external display panel 7. The in-finder display unit 38 drives the in-fine LEDs 26 and 27. The buzzer display section 39 produces a warning sound when displaying a warning or the like. The various circuits described above are comprehensively controlled by the CPU 40.

The operation of the first embodiment will be described with reference to the flow chart shown in FIG.

When the film is loaded and the back cover is closed in step 1, the film is fed by 3 frames in step 2 in an idle manner.

In step 3, it is determined whether the winding is performed properly. If it is not correct, the winding is tried again in step 4, and it is judged again in step 5 whether or not the winding is completed.

If the film is not wound properly due to some trouble, an abnormal film feeding mark 21 is displayed on the LCD display panel 7 above the camera in step 6, and the operation is stopped in step 7.

Normally, the jump feed in step 2 is performed correctly, so
After step 3, the relays are in a waiting state. In this state, shooting is performed from the start.

When the shutter is released in step 8, step 9
The state of the sequence switch group is determined by. If any of the switches is abnormal, the operation is stopped in step 7.

If there is no abnormality, the subject brightness is measured in step 10,
The exposure value is determined in consideration of the film sensitivity. Next, in step 11, the distance is measured using the AF sensor, and the taking lens 1 is extended to a predetermined position. As soon as the lens is extended to the correct position, the shutter is opened in step 12 to start exposure. In the case of a lens shutter type camera, in step 10, the exposure value is calculated, and then the aperture diameter of the shutter and the shutter speed are determined.

Simultaneously with the start of exposure, the film surface exposure amount monitor 31 starts operating in step 13, and the camera shake amount monitor 33 starts operating in step 14.

When the exposure is completed in step 15, the film surface exposure amount monitor 31 and the camera shake amount monitor 33 also stop their operations and store the measured values in their respective circuits. Immediately after the end of exposure, it is determined based on these measured values whether or not the current photographing is correctly performed.

First, in step 16, it is determined whether or not the correct exposure amount is applied to the film surface. The criterion for this determination is the exposure value calculated and determined in step 10. The predetermined exposure value and the exposure value measured by the film surface exposure amount monitor 31 are compared, and it is evaluated whether or not they match. Here, since some error can be tolerated, if the difference between the two is within an allowable range, it is determined to be normal. This tolerance may vary depending on the film type. For example, in the case of a negative film, correction can be made at the time of printing, so if the difference between the two is within ± 1 EV, it is determined to be normal. In the case of reversal film, if the difference between the two is within ± 0.3 EV, it is judged as abnormal. The switching of the allowable range may be performed automatically or manually.

If the exposure amount is not normal, the exposure abnormality mark 22 on the LCD panel 7 is blinked in step 17 to display a warning. In step 21, the NG red LED 27 is turned on in the viewfinder, and in step 22, the warning buzzer sounds. As a result, the photographer can be warned to take another image because the exposure amount on the film surface was not appropriate. Then, in step 23, one frame is wound for the next shooting. After this, in step 3, the completion of winding is checked.

If it is determined in step 16 that the exposure amount on the film surface is normal, the camera shake amount during film exposure is also determined in step 18 in the same manner. The reference value for this determination is a preset set value. This set value is compared with the shake amount measured by the camera shake amount monitor 33 to evaluate whether or not the measured shake amount is less than or equal to the set value. even here,
It is necessary to have an allowable range at the time of evaluation, but if the allowable range is taken into consideration when deciding the set value, a simple comparison may be made.

If the camera shake is not normal, go to step 19
The camera shake mark 23 on the panel 7 is blinked to display a warning. Then, as in the case of the abnormal exposure amount, the NG red LED 27 is turned on in the viewfinder in step 21, the warning buzzer is sounded in step 22, and the process proceeds to step 23.

If the camera shake amount is also normal, the green LED 26 for OK is turned on in the founder in step 20, and the process proceeds to step 23 to wind the film for the next shooting.

As described above, according to the first embodiment, the film surface exposure amount is monitored during shooting, compared with the exposure amount determined before shooting, and the result is warned, so that the shutter can be opened surely. Immediately after shooting, it can be determined whether the film surface has been properly exposed. Therefore, in the case of unexposed light, it is possible to prevent this by reimaging immediately. Further, by detecting the camera shake amount during exposure and issuing a warning of the result of comparison with a predetermined amount, it is possible to know immediately after shooting whether or not shooting has been performed without camera shake. If the amount of camera shake is large, take a picture again while paying attention to camera shake.
In this way, it is possible to know immediately after the shooting whether or not the current shooting has been performed correctly, it is possible to eliminate the fear of not knowing until the development, and it is possible to prevent the shooting failure.

Next, a second embodiment will be described. The same parts as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. The perspective view seen from the front is the same as FIG.

FIG. 8 is a view corresponding to FIG. 2 of the first embodiment and is a perspective view seen from the back surface. In addition to the configuration of the first embodiment,
In the Patrone room 10, DX touching the Patrone's DX code
A cord contact group 50 is provided.

The sectional view is the same as in FIG. LCD display panel is the fourth
It is the same as the figure without the camera shake mark 23.
The display section in the finder is the same as in FIG.

FIG. 9 is a block circuit diagram of a portion related to the determination of the film surface exposure amount in the control circuit. The other parts of the control circuit are the same as in the first embodiment.

The photometric element 14 'is connected to the integrating circuit 52, and the output of the integrating circuit 52 is input to the determination circuit 58. The AE photometric value from the AE photometric circuit 32 and the film speed information 60 and the latitude information 62 from the DX code contact group 50 are input to the determination circuit 58.
The output of the judgment circuit 58 is the "OK" mark LED26,
Connected to "NG" mark LED27.

FIG. 10 is a diagram showing details of the DX code printed on the side surface of the cartridge and the contact group 50 corresponding thereto. The contacts 71 and 77 are ground contacts, the contacts 72 to 76 indicate film sensitivity, and the contacts 81 and 82 indicate exposure latitude. EV is ± 1/2, ± 1, +2 depending on the film sensitivity.
~ 1, +3 ~ -1 is selected from four types. However, in an actual design, there is an error in the exposure amount determination circuit itself, so it may be better to give a slightly wider latitude.

 The operation of the second embodiment will be described.

When the shutter opens, the reflected light from the film surface is measured by the photometric element 14 ', and the condenser connected to the integrating circuit 52.
The photocurrent is integrated into 56 to obtain the exposure amount on the film surface. When the shutter is closed, the determination circuit 58 determines whether the exposure amount on the film surface is within the allowable range determined by the film sensitivity information and the latitude information. Judgment circuit 58
Lights one of the LEDs 26, 27 according to the judgment result,
A warning is displayed to indicate whether the shooting was successful or not.

The switch 54 connected to the integrating circuit 52 is for discharging and clearing the electric charge of the capacitor 56, and is kept on until just before the shutter is opened.

As described above, according to the second embodiment, the allowable range can be set according to the film sensitivity when determining the exposure amount on the film surface, so that the exposure amount can be determined more accurately.

〔The invention's effect〕

As described above, according to the present invention, it is determined whether or not the shooting operation is correctly performed during shooting, rather than issuing a warning about the shooting result predicted from the state before shooting, and the shooting operation is performed correctly. If not given, a warning is issued immediately after shooting, so that a camera is provided that enables the shooter to appropriately change shooting conditions according to the determination result.

[Brief description of the drawings]

FIG. 1 is a front perspective view of a first embodiment of a camera according to the present invention, FIG. 2 is a rear perspective view, FIG. 3 is a cross-sectional view, and FIG. 4 is a display example of an external display unit. 5, FIG. 5 is a diagram showing a display example of the display section in the finder, FIG. 6 is a block diagram of the control circuit, FIG. 7 is a flowchart showing the operation,
FIG. 8 is a perspective view of the second embodiment seen from the back side, FIG. 9 is a block diagram of a main part of the control circuit, and FIG. 10 is a diagram showing a DX code contact group. 14 '... Photometric element, 16,17 ... Acceleration sensor, 21, 22, 23
…… LCD warning mark, 26,27 …… Warning LED in viewfinder, 3
1 …… Film surface exposure monitor, 33 …… Camera shake monitor.

Claims (2)

(57) [Claims] 1. A means for calculating an appropriate exposure amount on a film surface based on subject brightness and a sensitivity of a film to be loaded, and a means for measuring an exposure amount on the film surface during exposure.
A first comparing means for comparing the proper exposure amount and the measured exposure amount after exposure and outputting a determination signal if the difference between the two is not within a predetermined allowable range, and information corresponding to the determination signal is displayed. A first display means for measuring the camera shake amount during exposure, comparing the measured shake amount with a predetermined value after the exposure, and outputting a determination signal that the measured shake amount is equal to or greater than the predetermined value. A camera comprising two comparing means and a second display means different from the first display means for outputting information according to the determination signal. 2. The camera according to claim 1, wherein the predetermined allowable range varies depending on film sensitivity.