JPH02143233A - Programmed automatic exposure device - Google Patents

Abstract

PURPOSE:To obtain a soft focus effect by calculating plural depths of focus from plural distance data obtained from plural points of an object and performing correction so that the shutter speed and aperture value can be shifted slightly from one side of the depth of focus. CONSTITUTION:When the always-open contact 1a of a soft focus button is closed through the 1st pushing operation, exposure operations are made during exposure time Tb with aperture data Fb followed by exposure operations of exposure time Ta with aperture data Fa. In this case, a main object to be photographed is sharply focused at the set position of a photographing lens, but a soft focus effect is obtained by the aperture data Fa which become out-of- depth of focus. Therefore, the soft focus effect can be obtained by only slightly changing the program logic for control without changing the parts for auto- focus.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a program automatic exposure device, and more particularly to a program automatic exposure device that can produce a soft focus effect for a plurality of subjects at different photographing distances.

[Prior Art and Problems to be Solved by the Invention] As disclosed in Japanese Patent Application No. 61-81512, a conventional program automatic exposure device has two methods for reliably focusing on two subjects located near and far. The depth of field element, the aperture value element which is the determining element of the depth of field, and the shutter speed (opening time element) determined by the aperture value are calculated to obtain the optimum combination of elements.

However, although the programmed automatic exposure device described above can achieve highly accurate focus, it is not possible to obtain a soft focus effect on the subject at the desired position.In order to obtain a soft focus effect, the lens must be driven again while the shutter is open. It is necessary to use a soft focus effect or use a soft focus filter. If the lens is to be driven again, the shutter drive and lens drive must be provided independently, which complicates the apparatus and makes it impossible to obtain a partial soft focus effect.

[Object of the Invention] The programmed automatic exposure device according to the present invention is based on the above-mentioned points, and is obtained from a plurality of points on the subject. ! A program that calculates multiple depths of focus from a number of distance data, and corrects the shutter speed and aperture value of the multiple calculated depths of focus so that they are slightly different from one of the depths of focus, resulting in a soft focus effect. The purpose is to provide an automatic exposure device.

[Means for Solving the Problems] To achieve the above object, the programmed automatic exposure i device according to the present invention is a programmed automatic exposure device that determines the exposure amount by matching the shutter speed and aperture value according to the brightness of the subject. a depth of focus calculation means for calculating the depth of focus based on distance data of the subject; and a first calculation means for calculating a first aperture value that is outside the range of the depth of focus calculated by the depth of focus calculation means; a second calculation means that calculates a second aperture value according to the brightness of the subject based on the first aperture value; and exposure control that performs a series of exposure operations using the first and second aperture values. It is equipped with means.

[Embodiment] A first embodiment of the program automatic exposure device according to the present invention is described below.
This will be explained according to the diagram.

As shown in Fig. 1, the program automatic exposure device includes a soft focus button 1, a control integrated circuit LSI (hereinafter simply LS
It is written as I. ), a motor drive circuit 13, an aperture and shutter drive motor 14, and a shutter 15.

The LSI has bins P1 to P7 and an output boat BUS,
Far distance, close-up distance detection circuit 4, autofocus circuit 4
a, object brightness detection circuit 5, first depth of focus calculation circuit 6,
Second depth of focus calculation circuit 7, first shutter speed/aperture value combination calculation circuit 8, second shutter speed/aperture value combination calculation circuit 9, combination data storage circuit IO, soft focus calculation circuit 11, exposure It is composed of a control IC 12.

The soft focus button 1 is composed of a non-locking button, and the normally open contact 1a or I is opened by the first and second button operations.
b is closed and sends a reference potential point to bin P1 or P2 of the LSI. Also, in the 31st locking operation, both the constant links ala and 1b are closed, and the bins P1 and P of S I are closed.
The reference potential point is sent to 2.

The far-wave object distance detection circuit 4 manually inputs the object distance signal IL output from the non-circuit 2 and outputs the far-wave object distance to the first focal depth calculation circuit 6 and the second S-point depth calculation circuit 7, respectively. Employment signal F 1. , outputs a slow wave photographic signal NL. The autofocus circuit 4a receives a subject distance signal IL and a subject brightness signal TB manually inputted from the distance measuring circuit 2, and sends a focus signal FOU to a microcomputer CPU (hereinafter simply referred to as CP (J)). The diaphragm aperture diameter data FF corresponding to FOU is sent to the eleventh negative point depth calculation circuit 6 and the second focal depth calculation circuit 7.

The first depth of focus calculation circuit 6 and the second depth of focus calculation circuit 'j3
7, the fast wave object distance signal FL, the slow wave object signal N17 and the aperture diameter data FF are manually input, and the depth data F
Z and NZ are input to the first shutter speed/aperture value combination calculation circuit 8
and is sent to the second shutter speed/aperture value combination calculation circuit 10.

The subject brightness calculation circuit 5 is ij,! I distance circuit 2 to LSI
The fast-wave object brightness signal BV+ and the lip-smacking object brightness signal BV2 are divided from the object brightness signal IB input through the bin P3, and the first object brightness signal output circuit 5a and the second object brightness signal output circuit 5b The fast wave photographic subject brightness signal BV+ and the lip-smacking subject brightness signal BV2 are sent to the first shutter speed/aperture value combination calculation circuit 8 and the second shutter speed/aperture value combination calculation circuit '189. .

A first shutter speed/aperture value combination calculation circuit 8 and a second shutter speed/aperture value combination calculation circuit 9 output a fast wave object distance signal FL, a fast wave object brightness signal B V The wave photographic object signal NL and the lip-smacking photographic object luminance signal BV2 are respectively inputted, and publication data FD, . is calculated and sent to the combined data storage circuit 10. Note that the first depth of focus calculation circuit 6 and the second depth of focus calculation circuit 7 convert the normal depth data FZ and NZ into the first shutter speed/aperture when the normally open contacts of the soft focus button are not both closed. It is sent to the value combination calculation circuit 8 and the second shutter speed/aperture value combination calculation circuit 9. The film sensitivity ISO set by the film sensitivity setting mechanism 3 is manually input to the CPU via the LSI bins P4 to P7 and the film sensitivity interface 3a, and each circuit is controlled by the CPU control lines C@ to C8. Therefore, in calculating the aperture value, the film sensitivity 150 set by the film sensitivity q constant mechanism 3 is referred to.

When the reference potential point is connected to the bin P1 or P2 of the LSI, the publication data FDll or ND, , 1 is calculated to have a soft focus. LSI bottle P
FD when both 1 and P2 are connected to the base 4 focal points
, and ND have soft focus.

[Soft focus calculation circuit] 1 is a scabbard alignment data recording circuit] Calculates aperture aperture diameter data Fb, Fa, exposure time Tb, Ta from depth data FD, ND0 stored in 0 and aperture aperture diameter data FF to control exposure. Send to IC12.

Exposure control ICI2 uses manual aperture aperture data Fa,
Output capo based on Fb and exposure time Ta, Tb) BUS
The motor drive circuit 13 is controlled via. The motor drive circuit 13 operates the shutter blade 15 of the shutter by the aperture and shutter drive motor 14 under the control of the exposure control IC 12.
5b, a series of aperture diameters Fa, Fb and exposure time Ta
, Tb.

Note that the focusing operation is performed using the focus signal F sent from the CPU.
Pre-caulking is performed by a focusing mechanism (not shown) by OU.

Further, the output of the exposure control IC 12 is transmitted to the shutter blade 15a.
, 15b and a signal for operating an aperture blade (not shown);
It is possible to operate an aperture control means using a liquid crystal or the like instead of the aperture blades.

[Function of the Invention] When the soft focus button 1 remains normal and the reference potential point of the movable contact [C] is not connected to the contacts 1a and 1b, the exposure operation is performed with normal cart focus.

When the normally open contact 1a is closed by the first push operation of the focus button 1, the exposure operation is performed for the exposure time Tb using the aperture diameter data Fb, and then the aperture diameter data is At Fa, the exposure operation is performed for the exposure time TaO. In this case, the main subject to be photographed is sharply focused at the set position of the photographic lens, but the soft focus effect is changed by the aperture diameter data F a that is outside the depth of focus ft.

On the other hand, if the main subject is close and you want the distant background to be in soft focus, change the shooting lens to a close-range lens.
q is determined, the aperture aperture data Fb and the exposure time Tb are O-opened, and the normally open contact 1b is closed by the second bushing operation so as to perform the exposure operation with the aperture aperture data Fc and the exposure time Tc. If you set this in advance, the third
The exposure characteristics shown by the dotted line in the figure are obtained. Soft focus button 1: 3rd button operation changes aperture aperture diameter data Fa, F
If b and exposure times Ta and Tb are both outside the depth of field, the entire image will be in soft focus.

The number of autofocus circuits 4a is not limited to one, and autofocus circuits 1a and 4bf2 may be provided in front of each of the first depth of focus calculation circuit 6 and the second depth of focus calculation circuit 7, and a subject distance detection circuit yδ4. , autofocus circuit 4a, object brightness detection circuit 5, first and second depth of focus calculation circuits 6.7, first and second shutter speed/aperture value combination calculation direction "l'38.9, silk matching data selection circuit 11 may be formed by program logic.

In the above embodiment, the subject brightness signal IB is manually input from the ill'l distance circuit 2 to the subject brightness detection circuit 5, and the fast-adjustment subject brightness signal B V + and the slow-wave subject brightness signal BV2 are detected. An optical circuit may also be provided. Also, 1llll
The fast-wave subject brightness signal ((■1) and slow-wave subject brightness signal BV2 output from the optical circuit are directly input to a single shutter speed/aperture value combination calculation circuit and serially processed to correspond to both distance and near. a first depth of focus calculation circuit, a second ju-point depth calculation circuit, a first shutter speed/aperture value combination calculation circuit, a second shutter combination data storage circuit, a first object brightness signal output circuit, and a second object brightness signal output circuit. In other words, the present invention includes the case where the first and second circuits are the same.

Note that the first and second shutter speed/aperture value combination calculation circuits 8 and 9 in the above embodiment may be first and second aperture (1α calculation circuits) that calculate only the first and second aperture values.

[Effects of the Invention] The program automatic exposure PitT' according to the present invention is a program automatic exposure device 1 that determines the exposure amount by adjusting the shutter speed and aperture value according to the brightness of the subject.
a depth of focus calculation means for calculating a depth of focus based on distance data of the subject; a first calculation means for calculating a first aperture value that is outside the range of the depth of focus calculated by the depth of focus calculation means; a second calculation means that calculates a second aperture f+tI according to the brightness of the subject based on the aperture value of; and an exposure control means that performs a series of exposure operations using the first and second aperture values. Because of this structure, a soft focus effect can be achieved by simply changing the control program logic slightly, without changing conventional autofocus components.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the program automatic exposure device according to the present invention, and FIGS. 2 and 3 are operational diagrams of the program automatic exposure device according to the present invention. 6...First depth of focus calculation circuit 7...
-Second depth of focus calculation circuit 8...First shutter speed/aperture value adjustment calculation circuit 9...Second shutter speed/aperture value adjustment calculation circuit

Claims (1)

[Claims] A program automatic exposure device that determines the exposure amount by a combination of a shutter speed and an aperture value depending on the brightness of a subject, a depth of focus calculation means for calculating a depth of focus based on distance data of the subject, and a depth of focus calculation means for calculating a depth of focus using the depth of focus calculation means. a first calculation means for calculating a first aperture value that is outside the range of the depth of focus; and a second calculation means for calculating a second aperture value corresponding to the brightness of the subject based on the first aperture value. A program automatic exposure device comprising: a calculation means; and an exposure control means for performing a series of exposure operations at the first and second aperture values.