JPH09325380A - Photographing device provided with ae locking function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable photographing with a suitable exposure, even if objects having the same composition are continuously photographed or different composition or an object is photographed by releasing a fixed exposure, when the angle of a lens with the object is out of a prescribed angle range. SOLUTION: When a release SW 18 is depressed, a CPU 20 supplies a control signal to a diaphragm 27, to make an aperture a stored stop value and then, to a shutter mechanism 28, to execute control so that a shutter curtain is opened only for a stored shutter speed time. Simultaneously, angle data from an angle sensor 10 at this time is stored in a memory 21. The angle and exposure data are released and returned to initial stage states, when an AE locking SW 17 is depressed again or the direction of a camera 1 is moved by >=5 deg. for instance from the direction at the releasing time. When the release SW 18 is depressed regardless of the fact that the angle and exposure data are not released, exposure with the same exposure data is attained many times, to execute photographing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvement of a photographing device such as a still camera, a video camera, a digital camera having an AE lock function.

[0002]

2. Description of the Related Art For example, a still camera (hereinafter, simply referred to as a "camera" including a video camera, a digital camera and the like) equipped with a conventional automatic exposure device of the related art is used to photograph an object in backlight. Then, the subject will appear dark due to the brightness of the background. Therefore, under such shooting conditions, various correction methods such as exposure correction and division metering and computer calculation are used, but this is only an estimation and lacks accuracy, so accurate exposure is required. In case of partial metering and AE lock (Auto E
xposure Lock: Abbreviation of automatic exposure lock) is often used.

In this method, as shown in FIG. 6, when it is desired to photograph a subject P, which is a person, in a bright background BG due to backlight, with the composition shown in FIG. As described above, the angle of the lens of the camera is changed, the subject P is placed in the center of the photometry range S, the exposure is measured, and the AE lock button is pressed. Then, as shown in FIG. Set the same composition and shoot again. By performing such an operation, the exposure of the main subject can be adjusted in any composition.

[0004]

However, such an active AE lock is released once a picture is taken, or is released by pressing the AE lock button again, and the automatic exposure is restored. For this reason, in the former case, even if you try to shoot several frames with the same composition in succession, different exposures will result in different exposures. In the latter case, you accidentally forget to release the AE lock button and shoot a completely different subject. If you do, there is a problem that the automatic exposure does not work, so you will be taken with an exposure that is not the proper exposure.

Therefore, in the present invention, the fixed exposure is released only when the exposure is fixed to the subject, the image is taken, and the movement of the camera is detected using the angle sensor, and when the AE lock button is pressed again. It is an object of the present invention to provide a camera capable of shooting with an appropriate exposure, even when shooting a subject having the same composition or shooting different compositions or subjects successively, by configuring as described above.

[0006]

Therefore, one embodiment of a camera with an AE lock function of the present invention is to provide a photographing means, an automatic exposure means, an exposure fixing means for fixing the exposure by the automatic exposure means, and a lens. Angle detecting means for detecting an angle with respect to the subject, and exposure releasing means for releasing the exposure fixed by the exposure fixing means when the angle of the lens with respect to the subject deviates from a predetermined angle range. Then, the said subject is solved.

Therefore, while the subject is continuously photographed with the same composition, it is possible to continue photographing with the same locked exposure, and when the camera is moved to photograph another subject, the previously locked exposure is automatically released. can do.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of an image pickup apparatus with an AE lock function according to the present invention will be described below with reference to FIGS. FIG. 1 is a conceptual external front view of a still camera with an AE lock function according to the present invention, FIG. 2 is a configuration diagram of the still camera with an AE lock function shown in FIG. 1, and FIG. 3 is an AE shown in FIG. FIG. 4 is a flow chart for explaining the operation of the still camera with a lock function, FIG. 4 is a configuration diagram for explaining the function of the angle detection means when the present invention is applied to a camera that can use an interchangeable lens, and FIG. FIG. 5 is a configuration diagram of an angle detecting means of an embodiment which can be used when the photographing apparatus with the AE lock function of the present invention is applied to a video camera.

1 and 2, reference numeral 1 indicates a camera with an AE lock function according to the present invention. This camera 1 has a main body 2 with a normal photographing function, for example, a lens 3 such as an interchangeable lens, a photometric device (13, 14, 15, etc.), a release switch (SW) 18, a finder 26, an aperture mechanism 27,
In addition to the shutter mechanism 28 and the like, the angle sensor 10 and the AE lock switch (SW) 17, which are angle detecting means, are provided.

In the camera 1 of this embodiment, as shown in FIG. 2, a central processing unit (CPU) 20 for calculating automatic exposure, calculating an angle of the camera 1 and making various judgments is mainly configured. And, on the input side of this CPU 20,
Camera angle (lens angle) of the state immediately before the subject
Angle sensor 1 to measure the current camera angle to
0, an A / D converter 11 for converting an analog signal into a digital signal, which is connected to the output side thereof, and a light receiving element 13 for measuring the brightness of the object P via a line 12, and an output side thereof. The connected photometric circuit 14 and A / D converter 15 are connected via a line 16, and the push button switches AE lock SW 17 and release SW 18 are connected, and the output side of the CPU 20 is connected via a line 22. The display circuit 25 for displaying “AEL” and the finder 26 connected to the output side thereof are
A diaphragm mechanism 27 that receives a control signal from the CPU 20 via a line 23 to adjust the aperture value, and also receives a control signal from the CPU 20 via a line 24 to adjust the shutter speed to open and close the shutter curtain. The mechanism 28 is connected, and the memory 21 for storing the exposure data and the angle or for inputting the stored data to the CPU 20 is connected to the other input / output terminal of the CPU 20. The camera 1 is configured. A gyroscope can be cited as an example of the angle sensor 10.

Next, the operation of the camera 1 will be described with reference to the flow chart shown in FIG. First, when the power source (not shown) of the camera 1 is turned on, the above-mentioned configuration circuit enters the "start" state in FIG. 3, and the CPU 20 sets the shutter speed according to the brightness of the subject P and the exposure mode set by the light receiving element 13. And the aperture value are calculated. If the brightness of the subject P changes at this time, the CPU 20 continues to calculate a value suitable for it at any time (step ST
1).

Once the AE lock SW 17 is pressed (step ST2), the CPU 20 stores the exposure data (shutter speed and aperture value) at that time in the memory 21, and at the same time supplies a signal to the display circuit 25 to cause the finder 2 to operate.
Make the “AEL” mark blink on 6 (step ST
3). In step ST2, when the AE lock SW 17 is not pressed, the CPU 20 continues to calculate a value suitable for the brightness of the subject P at any time. For the value of the exposure data measured by the CPU 20, press the AE lock SW 17 again (step ST
4) It is held in the memory 21 until the AE lock is released. In step ST4, press the AE lock SW17,
When the AE lock is released, the value of the exposure data held in the memory 21 is erased, the mode of the camera 1 returns to the exposure mode of step ST1, and the brightness of the subject is newly measured.

When the release SW 18 is pressed (step ST5), the CPU 20 supplies a control signal to the diaphragm mechanism 27 so that the diaphragm has the stored diaphragm value, and then supplies a control signal to the shutter mechanism 28 to store it. Control is performed so that the shutter curtain opens only for the time of the specified shutter speed (step ST6).

At the same time, the angle data from the angle sensor 10 at this time is stored in the memory 21. The angle data and the exposure data are released and returned to the initial state (step ST8) when the AE lock SW 17 is pressed again (step ST7) or when the direction of the camera 1 moves more than 5 ° from the time of release. If the release SW 18 is pressed before this is released (step ST9), the control from step ST7 onward is performed, and exposure can be performed with the same exposure data any number of times (step ST1).
0). In this state, the value by the angle sensor 10 is not updated.

As is apparent from the above description, the camera 1 of the present invention takes a picture after fixing the exposure to the object P and detects the movement of the camera 1 using the angle sensor 10, and the case where the camera P is forced. The fixed exposure can be released only when it is released. Therefore, it is possible to continuously shoot the subject having the same composition, and by repeating the above-described operation, it is possible to shoot with a proper exposure even when shooting a different composition or subject.

The present invention can be applied to a camera that can use various interchangeable lenses having different focal lengths. The longer the focal length of the lens (telephoto),
Even if you move by the same angle, the amount of change in composition will increase, so
The release angle 5 ° of the angle sensor 10 is changed according to the focal length of the lens.

For example, an arbitrary constant A / focal length (mm)
[°] When the arbitrary constant A is set to 500, (1) when using an interchangeable lens with a focal length of 25 mm: 20 ° (2) when using an interchangeable lens with a focal length of 50 mm: 10 ° (3) interchangeable with a focal length of 100 mm When using a lens: 5 ° (4) When using an interchangeable lens having a focal length of 200 mm: The release angle is changed to 2.5 °.

In a camera in which the interchangeable lens 3A can be used, as shown in FIG. 4, when interchangeable lenses 3A having different focal lengths are attached to the main body 2, lens data such as the focal length is sent to the CPU 20. It is configured to be. Therefore, by using this function, if the release angle for each focal length when the interchangeable lens 3A is used is set in the CPU 20 in advance, even if a different interchangeable lens is used, the subject P in the backlight is properly exposed. Can be taken at.

FIG. 5 shows an AE lock release sensor 30 when the video camera is equipped with an AE lock release function. The sensor 30 includes a CCD 31 and a CCD 3
1. An A / D converter 32 for A / D converting the video signal taken in 1, a Y / C separator 33 for separating the A / D converted video signal into image data and color component data, and front / back separation It is composed of a motion detection circuit 34 including a memory 34A and a comparator 34B for comparing the image data.

Therefore, through the lens of the video camera, C
The image in the CD 31 is stored in the memory 34 as image data.
It is possible to detect the movement of the subject or the movement of the camera by comparing the image data before and after stored in A with the comparator 34B, and release the AE lock by the control signal 35 obtained at the output side thereof. Therefore, it can be seen that the AE lock can be released without the angle sensor 10 as described above. Further, since the AE lock release sensor 30 of the present embodiment can detect not only the movement angle of the camera but also the movement of the subject itself, the AE lock can be released even when the subject moves largely without moving the camera. You can

[0021]

As is apparent from the above description, the camera with the AE lock function of the present invention can keep shooting with the same locked exposure while the subject is continuously shot with the same composition. The previous locked exposure can be automatically released when you try to shoot another subject. Therefore, it is possible to prevent mistakes such as shooting the second and subsequent images with incorrect exposure such as automatic exposure under backlighting and shooting different subjects with the previous exposure, and to eliminate waste of film and magnetic tape. You can capture the target moment.

[Brief description of drawings]

FIG. 1 is a conceptual external front view of a still camera with an AE lock function of the present invention.

FIG. 2 is a configuration diagram of the still camera with the AE lock function shown in FIG.

FIG. 3 is a flowchart for explaining the operation of the still camera with the AE lock function shown in FIG.

FIG. 4 is a configuration diagram for explaining a function of angle detection means when the present invention is applied to a camera that can use an interchangeable lens.

FIG. 5 is a configuration diagram of an angle detecting means of an embodiment which can be used when the image pickup apparatus with the AE lock function of the present invention is applied to a video camera.

FIG. 6 is an explanatory diagram when a subject on a bright background due to backlight is photographed.

[Explanation of symbols]

1 ... Camera of the present invention with AE lock function, 2 ... Main body, 3
… Lens, 3A… Interchangeable lens, 10… Angle sensor, 1
DESCRIPTION OF SYMBOLS 1 ... A / D converter, 13 ... Light receiving element, 14 ... Photometric circuit, 15 ... A / D converter, 17 ... AE lock SW,
18 ... Release SW, 20 ... CPU, 21, 34A ... Memory, 25 ... Display circuit, 26 ... Finder, 27 ...
Aperture mechanism, 28 ... Shutter mechanism, 30 ... AE lock release sensor, 31 ... CCD, 32 ... A / D converter,
33 ... Y / C separator, 34 ... Motion detection circuit

Claims (3)

[Claims] 1. A photographing means, an automatic exposure means, an exposure fixing means for fixing the exposure by the automatic exposure means, an angle detection means for detecting an angle of the lens with respect to the subject, and an angle detection means with respect to the subject of the lens. An imaging device with an AE lock function, comprising: an exposure releasing means for releasing the exposure fixed by the exposure fixing means when the angle is out of a predetermined angle range. 2. The AE lock function according to claim 1, wherein the predetermined angle range of the lens of the angle detecting means with respect to the subject is automatically changed by exchanging lenses having different focal lengths. Imaging device. 3. A photographing means, an automatic exposure means, an exposure fixing means for fixing the exposure by the automatic exposure means, a movement detecting means for detecting relative movement between the lens and an object, and a lens by the movement detecting means. And an exposure releasing means for releasing the exposure fixed by the exposure fixing means when the relative movement of the subject before and after photographing deviates from a predetermined movement range. Imaging device.