JPH05215961A - Automatic photographing device for camera - Google Patents

Abstract

PURPOSE:To execute photographing at prescribed timing even if an object is not in depth of field by permitting release when a range-finding value is in a range set in advance, wider than depth of focus centering on the distance of an object. CONSTITUTION:A CPU 7 controls a range finder 3, to repeat a range-finding action, and judges whether the obtained latest range-finding value D satisfies the conditions of an equation, or not. At this time, alpha and beta are values which are greater than half of the depth of focus of a photographic optical system 4, and stored in a RAM 6 in advance. When it is judged that the measurement value D is in the range, the CPU 7 allows the range-finder 3 to take the range- finding action, again. Thus, the final distance is measured. In other words, the CPU 7 controls the photographic optical system, in accordance with the latest range-finding value obtained by range-finding, to adjust a focal distance. When the adjustment of the focal distance is completed, automatic photographing is executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera automatic photographing device suitable for use in a camera having a focus lock function.

[0002]

2. Description of the Related Art A camera having a focus lock function is capable of focus-locking a pseudo subject, and then pointing the camera at the original subject and taking a picture in the locked state of the original subject. When it is in the possible position, the release is automatically performed. Such a technique is disclosed in, for example,
No. 4095.

Further, for example, in Japanese Unexamined Patent Publication No. 3-212635 or Japanese Unexamined Patent Publication No. 3-213838, a release operation is performed when a distance measurement value at the start of a sequence in an auto self mode and a distance measurement value thereafter change. It is suggested to start.

[0004]

However, of the above-mentioned devices, in the former case, if the subject is not within the depth of field at the set distance, the image cannot be focused because it cannot be focused. As a result, there was a risk of missing a photo opportunity.

Further, in the latter case, there is a problem that the release operation is started at a timing different from the intention of the photographer, for example, when a passerby crosses in front of the original subject.

The present invention has been made in view of such a situation, and it is possible to surely perform photographing at a predetermined timing even when the subject is not within the depth of field at a preset distance. It is something to do.

[0007]

An automatic photographing apparatus for a camera according to the present invention comprises a switch 2 as a setting means for setting a subject distance for photographing, and a distance measuring means for repeating a distance measuring operation after setting the subject distance. Distance measuring device 3, a photographing optical system 4 as a photographing means for adjusting the focus in accordance with the distance measuring result of the distance measuring device 3, and the distance measured by the distance measuring device 3 with the object distance as the center. It is characterized in that it is provided with a CPU 7 as a control means for permitting a release when a value in a predetermined range wider than the depth of focus is reached.

The distance measuring device 3 measures the distance again when the distance measured value falls within a predetermined range, and the photographing optical system 4 adjusts the focus in accordance with the latest distance measuring result. You can

[0009]

In the automatic photographing device of the camera having the above structure,
The distance measurement value is wider than the depth of focus, centered on the subject distance,
The release is permitted when the value is within a predetermined range set in advance. Therefore, even when the subject is slightly away from the preset subject distance, it is possible to surely perform shooting at a predetermined timing.

[0010]

2 is a perspective view showing the construction of an embodiment of a camera to which the present invention is applied. A photographing optical system 4 including a photographing lens is mounted on the front surface of the camera body 10. Further, a distance measuring device 3 for measuring the distance to the subject is provided above it. On the right side of the upper surface of the main body 10, a release button 1 that is operated when releasing is provided, and on the left side thereof, a mode selection button 2 is provided. The mode selection button 2 is operated when the self mode or the catch-in focus mode is set.

FIG. 1 shows an embodiment of the electrical construction of an automatic image pickup apparatus for a camera according to the present invention. CPU7 is RO
The shooting operation is controlled according to a program stored in advance in M5. Switches 1f and 1h
Are turned on when the release button 1 is pressed halfway or fully. The RAM 6 is configured to store data obtained as a result of distance measurement by the distance measuring device 3 and other data as needed.

Next, the operation will be described with reference to the flowchart of FIG. When the catch-in focus mode is set by operating the mode selection button 2, the processing shown in the flowchart of FIG. 3 is executed. First step S1
At, a predetermined distance is set. This distance is set as follows. For example, when the release button 1 is pressed halfway down and the switch 1f is turned on, the CPU 7 controls the distance measuring device 3 to measure the distance to the object to which the camera is directed at that time. The distance measurement value L of the distance measurement device 3 at the timing when the release button 1 is released and the switch 1f is turned off is stored in the RAM 6. That is, the focus is locked by pointing the camera toward the temporary subject and pressing the release button 1 halfway.

Alternatively, it goes without saying that a predetermined distance may be manually input instead of the focus lock.

When the distance is thus set, the CPU 7 then proceeds to step S2 to control the distance measuring device 3 to repeatedly execute the distance measuring operation. The CPU 7 determines in step S3 whether or not the latest distance measurement value D obtained as a result of distance measurement in step S2 satisfies the following condition. L−α ≦ D ≦ L + β where α and β are values larger than ½ of the depth of focus of the photographing optical system 4 and values stored in advance in the RAM 6, and should be set to 2 m, for example. You can This value may be fixed, or the operator may change it to any value as needed.

When the distance measurement value D obtained as a result of the distance measurement in step S2 is not within the above range, the CPU 7 returns to step S2 and repeats the distance measurement operation. When it is determined that the distance measurement value D is within the above range, the process proceeds to step S4, and the CPU 7 controls the distance measurement device 3 again to execute the distance measurement operation. As a result, the distance to the final subject is measured. Next, in step S5, shooting is performed. That is, the CPU 7 controls the photographing optical system 4 and controls the photographing optical system 4 in accordance with the latest distance measurement value obtained as a result of the distance measurement in step S4 to adjust the focus. Then, when the adjustment of the focus is completed, the photographing is automatically executed.

In the above description, when it is determined in step S3 that the distance measurement value D is within the predetermined range, the process immediately proceeds to step S4 to perform the final distance measurement. It is also possible to insert a step of waiting for a certain period of time so that the final distance measurement is performed at a timing when a predetermined time has elapsed after the distance measurement value D entered a predetermined range.

FIG. 4 is a diagram for explaining the above operation. That is, in step S1, the distance L from the film 11 built in the main body 10 to the subject 12 is set. This distance L is set using a temporary subject instead of the original subject. That is, for example, when the photographer wants to take a picture of himself against a certain background, the camera is installed on a stand, and the distance from that position to the position where he is supposed to be for shooting seems to be equal. A pseudo object located at a certain distance is found, the camera 10 is pointed at the pseudo object, and the focus of the pseudo object is locked. As a result, the distance L is set.

Next, the camera body 10 is turned to the direction in which it is desired to shoot. After that, the photographer himself moves to the position where the camera is turned, and faces the camera body 10. At this time, the distance between the camera body 10 and the subject 12 is a distance substantially corresponding to the distance L. Therefore, the camera body 1
When the distance D between 0 and the subject 12 is within the range regulated by L-α and L + β, the distance measuring operation is performed again,
Shooting is performed in correspondence with the distance measurement value.

When the focal depth of the photographing optical system 4 is δ,
In the conventional apparatus, the photographing is performed only when the subject 12 is within the range of L ± δ / 2, but in the present embodiment, α + β wider than δ.
When the subject 12 is within the range, the photographing is performed. That is, A (= α-δ / 2) or B exceeding the depth of focus δ
Imaging is executed even within the range of (= β−δ / 2). Then, since the final distance measurement is performed in step S4, the subject 1 is placed in this range A or B.
Even when 2 is located, out-of-focus blurring does not occur. Of course, if a passerby crosses outside the range of α + β, the release is not allowed, so that the release operation is prevented from being started at a timing not intended by the photographer.

[0020]

As described above, according to the automatic photographing apparatus for a camera of the present invention, the release is allowed when the distance measurement value becomes a value within a predetermined range wider than the depth of focus around the subject distance. Therefore, it is possible to reliably and automatically shoot a subject at a predetermined timing without missing a photo opportunity.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of an automatic image capturing apparatus for a camera of the present invention.

FIG. 2 is a perspective view showing a configuration of a camera.

FIG. 3 is a flowchart illustrating the operation of the embodiment of FIG.

FIG. 4 is a conceptual diagram illustrating an operation of the embodiment of FIG.

[Explanation of symbols]

 1 Release button 2 Mode selection button 3 Distance measuring device 4 Photographing optical system 5 ROM 6 RAM 7 CPU

Claims (2)

[Claims] 1. A setting means for setting a subject distance for photographing, a distance measuring means for repeatedly performing a distance measuring operation after setting the subject distance, and a focus adjustment corresponding to a distance measuring result of the distance measuring means. And a control means for permitting the release when the distance measurement value by the distance measurement means becomes a value that is wider than the depth of focus and is within a predetermined range centered on the subject distance. An automatic image capturing device for a camera. 2. The distance measuring means measures the distance again when the distance measuring value becomes a value within the predetermined range, and the adjusting means focuses on the result of the latest distance measuring. The automatic image capturing device for a camera according to claim 1, wherein