JPH01197711A - Camera operation controller - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a camera operation control device, and is particularly aimed at making effective use of depth of field.

B. Conventional technology and its problems In conventional cameras, for example, the photographing lens is driven to the photographing distance calculated based on the H1'l distance information from the distance measuring circuit, that is, the photographing distance that focuses on the subject. It is carried out.

By the way, when the photographing lens is driven to an arbitrary photographing distance, the farthest point of the depth of field becomes infinity.

This shooting distance is called the hyperfocal distance. For example, Fig. 3(a)
As shown in , when the shooting distance a based on the distance measurement information is located farther than the hyperfocal distance aB, when the shooting lens is driven to the shooting distance a1, the farthest point d2 of the depth of field becomes greater than infinity. Therefore, the closest point d exists on the far side by Δd1 from the closest point cts of the depth of field when the photographic lens is driven to the hyperfocal distance. Therefore, when photographing is performed at the photographing distance a1, an object existing at a distance of Δd from the nearest point d becomes blurred compared to when photographing is performed at the hyperfocal distance a9, and the depth of field is not effectively utilized. Particularly when the brightness of the subject is high, the depth of field becomes deeper as the aperture is narrowed down, and there are many situations where effective utilization cannot be achieved.

An object of the present invention is to provide a camera operation control device that makes effective use of depth of field.

To explain with reference to FIG. 1, which is a means for solving the C0 problem and a diagram corresponding to complaints, the present invention has a distance information output means 101 that outputs distance information regarding the distance to the subject, and an aperture that outputs the set aperture value. A value output means 102, a focal length information output means 104 that outputs focal length information of the photographic lens 103, and a first calculation means that calculates a first photographing distance to focus on the subject based on the distance information. 105 and a driving means 106 for driving the photographing lens 103 for focusing. The above-mentioned problem is exacerbated by the set aperture value and focal length information, so that either the nearest point or the farthest point of the depth of field is a predetermined shooting distance M (for example, infinity or the closest point). a second calculation means 107 that calculates a second photographing distance such that;
Mode setting means 108 for setting depth of field priority mode
When the depth of field priority mode is set, if the first shooting distance is outside the depth of field, the shooting lens 103 is set to the first shooting distance.
The driving means 106 is controlled to drive to the first shooting distance.
If the photographing distance is within the depth of field, the driving means 106 drives the photographing lens 103 to the second photographing distance.
This problem can be solved by providing a control means 109 for controlling.

00 action control means 109 controls the first
If the first photographing distance calculated by the calculating means 105 is outside the depth of field at the second photographing distance calculated by the second calculating means 107, the photographing lens 1
03 to a first photographing distance, and when the first photographing distance is within the depth of field, the photographing lens 103 is driven to a second photographing distance. controlling means 106;

E. Embodiment An embodiment of the present invention will be described based on FIGS. 2 to 4.

In FIG. 2, a control circuit 1 is connected to a photometry circuit 2, a distance measurement circuit 3, and a lens information circuit 4 for a photographic lens. The photometry circuit 2 outputs brightness information regarding the brightness of the subject, and the distance measurement circuit 3 outputs distance measurement information regarding the distance to the subject. The lens information circuit 4 outputs information such as the focal length of the photographic lens.

Further, connected to the control circuit 1 are a lens drive circuit 5 that drives a photographing lens by a focusing motor, an exposure control circuit 6, and switches SWI and SW2 that are turned on in conjunction with the operation of a release button (not shown). switch S
WI is turned on when the release button is pressed halfway, and the switch SW is turned on.
2 turns on when pressed fully. The control circuit 1 includes a switch S
When WI is turned on, the above-mentioned photometry circuit 2. The distance measuring circuit 3 is activated and the switch SW2 is turned on to calculate the photographing distance a1 based on the distance measuring information from the distance measuring circuit 3.
The aperture value F etc. are calculated based on the brightness information from the photometry circuit 2. When the depth of field priority mode, which will be described later, is not set, the motor 7 is operated via the lens drive circuit 5.
The photographing lens is driven to the photographing distance a0, and the exposure control circuit 6 drives the aperture (not shown) to the aperture value F, and at the same time drives the shutter device to take a picture.

Further, the control circuit 1 is connected to a switch SW3 and a display circuit 8 for setting a depth of field priority mode as described later. The switch SW3 is turned on in conjunction with the operation of a depth of field priority mode setting button (not shown), and the control circuit 1
When the depth of field priority mode is set by turning on the switch SW3, a message to that effect is displayed in the viewfinder via the display circuit 8. When the depth of field priority mode is set, the control circuit 1 calculates the closest point of the depth of field when the photographing lens is driven to the hyperfocal distance as and the hyperfocal distance a5, as described below.

FIGS. 3(a) and 3(b) are diagrams showing a comparison between the depth of field at the photographing distance determined based on distance measurement information and the depth of field at the hyperfocal distance, respectively. Now, the aperture value calculated based on the brightness information from the photometry circuit 2 is F, and the focal length of the photographing lens obtained from the lens information circuit 4 is f.
, the allowable circle of confusion diameter is E, then the shooting distance calculated based on the distance measurement information from the distance measurement circuit 3, that is, the recent depth of field when the shooting lens is at the shooting distance a1 that focuses on the subject. The point d and the farthest point d2 are each expressed as follows. That is, the depth of field is between d and d2, and when photographing is performed at the photographing distance aL, the subject existing between d and -62 is clearly photographed.

Here, the permissible diameter of the circle of confusion is the diameter of the maximum blur that is not recognized as blur by the human eye.

The hyperfocal distance a9 is the distance at which the farthest point of the depth of field becomes infinity when the photographic lens is driven here, and is found by setting d to ω in the second equation above. . In other words, the hyperfocal distance aB is as=f”/ (F ・E) (3)
It is determined by By substituting this equation into the first equation, the nearest point ds can be obtained.

When the depth of field priority mode is set, the control circuit 1 compares the shooting distance a calculated based on the distance measurement information from the distance measurement circuit 3 and the nearest point dat calculated from the above-mentioned formula 4. However, if at>dsi, the photographing lens is driven to the hyperfocal distance as.

In the configuration of the above embodiment, the distance measuring circuit 3 serves as the distance information output means 101, the photometry circuit 2 and the control circuit 1 serve as the aperture value output means 102, the lens drive circuit 5 and the motor 5 serve as the drive means 106, and the switch SW3 The control circuit 1 operates the mode setting means 108, the control means 1 operates the focal length information output means 104, the first . Second calculation means 105, 107 and control means 109 are respectively configured.

Next, the control procedure performed within the control circuit 1 will be explained with reference to the flowchart shown in FIG.

In FIG. 4, when the half-press switch SWI is turned on, this program is started, and first, in step S1, brightness information from the photometry circuit 2 and photometry information from the distance measurement circuit 3 are read, and at the same time, in step S2, the brightness information from the lens information circuit 4 is read. Read the focal length f of the photographic lens. Then step S
3, it is determined whether the depth of field priority mode is set depending on whether the switch SW3 is turned on.

If the determination is negative, the process proceeds to step S5, and if the determination is affirmative, the display circuit 8 displays in the finder in step S4 that the depth of field priority mode is set, and the process proceeds to step S5.

In step S5, it is determined whether or not the full-press switch SW2 is on. If the determination is affirmative, the process proceeds to step S6, and if the determination is negative, it is determined in step 815 whether the half-press switch SWI is on. If step S15 is affirmed, the process returns to step S5, and if negative, the process is terminated.

In step S6, the photographing distance (first photographing distance) al at which the subject is focused is calculated based on the read distance measurement information. Next, in step S7, the brightness information from the photometric circuit 2 is read again, and in step S8, the aperture value F is calculated from this brightness information, and the process proceeds to step S9. In step S9, it is determined whether the depth of field priority mode is set,
If the determination is negative, the process proceeds to step 316, and if the determination is affirmative, the process proceeds to step SIO. In step SIO, a hyperfocal distance (second photographing distance) a3 is calculated from the third equation based on the focal length f of the photographing lens read in step S2 and the aperture value F calculated in step S8, and
From this hyperfocal distance aB, the nearest point ds is
1 and proceeds to step 811.

In step Sll, it is determined whether the photographing distance a0 calculated in step S6 is located farther than the nearest point dsi calculated in step S10, that is, whether or not a>ds□, If a negative determination is made, step S16
In step S16, the photographing distance a calculated in step S6 is determined by the motor 7 via the lens drive circuit 5.
Then, in step S13, the diaphragm and shutter device are driven through the exposure control port 'tPt6 to take a picture.Then, in step 814, the film is wound by one frame, and the process is completed.

Moreover, if step Sll is affirmed, that is, ill
! If the photographing distance a1 based on l distance information is located farther than the nearest point ds at the hyperfocal distance a3, step S
12, the photographing lens is driven to the hyperfocal distance a3 calculated in step S10, and then in step S13. S
At step 14, photographing and film winding are performed.

According to the above procedure, when the depth of field priority mode is set, the shooting distance a1 based on the ranging information is farther than the nearest point d8x of the depth of field when the shooting lens is driven to the hyperfocal distance a3. If it exists.

The photographing lens is driven to the hyperfocal distance a9 and photographing is performed. Therefore, as shown in FIG. 3(a'), when the photographing distance a1 is located farther than the hyperfocal distance as, the illustration shows the case where the photographing lens is driven to the photographing distance a1 and photographing is performed. A subject that is closer by Δd4 is clearly photographed. In addition, as shown in Fig. 3(b), the shooting distance a is tNE between the hyperfocal distance a3 and the closest point of the depth of field.
In this case, an object that is further away by Δd2 in the figure is clearly photographed compared to the case where the photographing lens is driven one time at the photographing distance a.

-Modification- Furthermore, as shown in FIG. 5, after the processing in steps 81 to S10, in step S21 the photographing distance a0 is
It is determined whether the distance is farther than 3, that is, a □) a 3. If negative, the photographing lens is driven to the photographing distance a in step 316, and if affirmative, step SL is performed.
In step 2, the photographing lens may be driven to the hyperfocal distance a3 to take photographs.

In the above, the hyperfocal distance a3 obtained when the farthest point of the depth of field is set to infinity is set, and when the depth of field priority mode is set, the shooting path m a 1 based on distance measurement information is If the object is located further away than the nearest point of the depth of field, the photographing lens is driven to the hyperfocal distance to take the photograph.
For example, as shown in Fig. 6 (n) and (b), when setting the shooting distance aH obtained when the nearest point of the depth of field is the closest point (N), and setting the depth of field priority mode, , if the photographing distance a□ based on the distance measurement information is closer than the farthest point dT of the depth of field at the photographing distance aNx, the photographing lens is driven to this photographing distance a)4. Photographing may also be performed.

According to this, as shown in FIG. 6(a), the shooting path '11
If 1 a x is closer than the photographing distance a)4, the object located further away by Δd in the figure will be clear compared to when the photographic lens is driven to the photographing distance a. Being photographed. Further, as shown in FIG. 6(b), when the photographing distance a1 exists between the photographing distance aN and the farthest point of the depth of field.

Compared to the case where the photographing lens is driven to the photographing distance a1 and the photograph is taken, the object which is closer by Δd in the figure is clearly photographed.

In addition, the specific shooting pressure that can be obtained when either the nearest point or the farthest point of the depth of field is set to a specific shooting distance within the range from the closest point to infinity is set, and the shooting path Ma
1 exists behind the nearest point of the depth of field and in front of the farthest point, the photographing lens may be driven to a specific photographing distance.

F0 Effects of the Invention According to the present invention, when the depth of field priority mode is set, the first shooting distance based on distance measurement information is such that either the nearest point or the farthest point of the depth of field is infinity or If the object is within the depth of field at the second shooting distance, such as the closest distance, the photographing lens is driven to the second shooting distance to take a picture. The depth of field can be used more effectively than when shooting at a shooting distance of .

[Brief explanation of the drawing]

FIG. 1 is a complaint correspondence diagram. Figures 2 to 4 show an embodiment of the present invention, Figure 2 is an overall configuration diagram of the camera operation control device according to the present invention, and Figures 3 (a) and (b) are focused on the subject. Fig. 4 is a flowchart 1 showing the processing procedure, and Fig. 5 is a modification of the processing. flowchart,
FIGS. 6(a) and 6(b) are FIG. 3(a) showing a modified example. It is a figure corresponding to (b). 2: Photometer circuit 3: Distance measurement circuit 5: Lens! Pivoting circuit 7: Motor 101: Distance information output means 102: Aperture value output means 103: Photographic lens 104: Focal length information output means 105: First calculation means 106: Driving means 107: Second calculation means 108: Mode Setting means 109: Control means SWI to SW3: Switch patent applicant: Nippon Kogaku Kogyo Co., Ltd. Representative Patent Attorney Fuyu Nagai Noriyuki Figure 2

Claims (1)

[Scope of Claims] 1) Distance information output means that outputs distance information regarding the distance to the subject; Aperture value output means that outputs a set aperture value; and Focal length information output means that outputs focal length information of a photographic lens. and a camera operation control device comprising: a first calculating means for calculating a first photographing distance to focus on the subject based on the distance information; and a driving means for driving a photographing lens for focusing. a second calculation means for calculating a second photographing distance such that either the nearest point or the farthest point of the depth of field is a predetermined photographing distance, based on the set aperture value and the focal length information; and a mode setting means for setting a depth of field priority mode, and when the depth of field priority mode is set and the first photographing distance is outside the depth of field, the photographing lens is set to the depth of field. The driving means is controlled to drive the photographing lens to the first photographing distance, and when the first photographing distance is within the depth of field, the photographing lens is driven to the second photographing distance. 1. A camera operation control device comprising: a control means for controlling a drive means. 2) The second calculation means calculates the hyperfocal distance obtained when the farthest point of the depth of field is set to infinity, and the control means calculates the hyperfocal distance obtained when the farthest point of the depth of field is set to infinity, and the control means If the first photographing distance exists behind the closest point of depth, the photographing lens is driven to the second photographing distance, and the first photographing distance exists in front of the closest point. In this case, the photographing lens is driven to the first photographing distance.
The camera operation control device described in 2. 3) The second calculation means calculates, as the second photographing distance, a photographing distance obtained when the nearest point of the depth of field is the closest point, and the control means When the first photographing distance exists in front of the farthest point of the depth of field, the photographing lens is driven to the second photographing distance, and the first photographing distance exists behind the farthest point of the depth of field. 1
2. The camera operation control device according to claim 1, wherein the camera operation control device drives the photographing lens to the first photographing distance when the photographing distance exists. 4) The second calculation means calculates a specific shooting distance that is obtained when either the nearest point or the farthest point of the depth of field is set to a specific shooting distance within a range from the closest point to infinity. is calculated as the second photographing distance, and the control means determines that the first photographing distance exists behind the nearest point of the depth of field and in front of the farthest point of the depth of field. In this case, the photographing lens is driven to the second photographing distance, and the first photographing distance is located in front of the nearest point of the depth of field or behind the farthest point of the depth of field. 2. The camera operation control device according to claim 1, wherein the camera operation control device is configured to drive the photographing lens to the first photographing distance.