JPH049831A - Camera - Google Patents

Abstract

PURPOSE:To allow a beginner to execute photographing with the optimum sensitivity by displaying how many times of sensitization or desensitization is proper under a state that photometry is executed. CONSTITUTION:A photometry circuit 7 executes the photometry of a field to be photographed and sends the output of the photometry to a microcomputer 1 under the control of the computer 1. By the computer 1, the sent output of the photometry is A/D-converted an used for setting an exposure condition. That means, when a photographer sets it by using the switch sense circuit 4 of a film and executes the photometry, the computer 1 calculates and decides a stop value and a shutter speed value. Then, the calculated and decided shutter speed value and a focal distance received by lens communication are compared and the proper sensitization or desensitization multiple which makes a shutter speed higher within a half step than 1/(focal distance) is calculated. Then, it is displayed on a display member. Thus, even the beginner executes the photographing by the optimum sensitivity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a camera that has a built-in exposure meter and is capable of recognizing the focal length of a lens.

[Prior Art] When loading film into a camera, photographers judge by their intuition which film sensitivity is best.

Therefore, the present inventor proposed displaying a sensitivity of 130, which is determined to be optimal in the situation in which photometry is performed.

[Problems to be Solved by the Invention] However, it is not always the case that the photographer has a film with the displayed optimal ISO sensitivity at the shooting location. Furthermore, depending on the price of the film or the ease of obtaining the film, there may be cases where a particular film is desired to be used.

[Means (and effects) for solving the problem] Therefore, a means for determining the aperture value and shutter speed by incorporating an exposure meter, a means for recognizing the focal length of the lens, and a display means are provided. The situation in which light metering was performed using the light metering value measured by the built-in exposure meter, the focal length of the attached lens, the combination of aperture and shutter speed depending on the brightness, and the sensitivity of the photographic film. rsoWA of the film planned to be used.
To display how many times the sensitization and sensitivity should be optimally performed, and to enable the setting of the photographic film sensitivity to be reset after confirmation.

Embodiment FIG. 1 is an electrical control block diagram of a camera embodying the present invention. 1 is a microcomputer that controls the movement of each part of the camera. Reference numeral 2 denotes a lens control circuit that drives and controls a focus adjustment motor and an aperture blade control motor of a photographing lens (not shown). The lens 11J control circuit 2 performs serial communication via DBUS while receiving the LCOM signal from the microcomputer 1. Receives motor drive information through serial communication, and controls the motor based on that information. At the same time, various information about the lens (focal length, etc.) is sent to the microcomputer 1 via serial communication.

Reference numeral 3 denotes a liquid crystal display circuit, which drives a liquid crystal display (not shown) for informing the photographer of various photographic information of the camera, such as shutter speed, aperture value, 130 sensitivity, number of films, etc. While the liquid crystal display circuit 3 receives the DPCOM signal from the microcomputer 1, the DBU
Serial communication is performed via S. Display data is received and received through serial communication, and the liquid crystal display is driven according to the data. Reference numeral 4 designates a switch sense circuit, which is a circuit that reads the status of the Meda switch used by the photographer to set each photography condition and the status of the switch indicating the status of the camera and sends it to the microcomputer 1. While receiving the SWCOM signal, the DBU
Microcomputer-1 by serial communication via S
Send switch data to.

Reference numeral 5 denotes a strobe light emission dimming control circuit, which controls the generation of strobe light and the light emission stop function by TTL dimming.

While receiving the STCOM signal, the strobe light emission dimming control circuit 5 serially communicates with the microcomputer 1 via DBUS to receive data related to strobe control and performs various controls.

Reference numeral 6 is a focus detection circuit, which is a unit consisting of a line sensor for performing AF using the existing phase difference detection method and a circuit for reading out its accumulation.
Control is performed by

Reference numeral 7 denotes a photometry circuit, which performs photometry of the object field and sends a photometry output to the microcomputer under the control of the microcomputer 1. The microcomputer 1 A/D converts the sent photometric output and uses it to set exposure conditions.

Reference numeral 8 denotes a shutter control circuit that controls the movement of the front and rear curtains of the shutter (not shown) according to control signals from the microcomputer 1. 9 is a feeding circuit and microcomputer-1
A feed motor (not shown) is controlled in accordance with control signals from the camera to feed, wind, and rewind the film.

SWl is linked to the camera's release button.
When the microcomputer 1 recognizes that I has been turned on, it starts the exposure operation.

The X contact turns ON at the timing when the front curtain of the shutter completes its travel.
, serves to notify the strobe light emission control circuit 5 of the timing of strobe light emission.

Next, the flow of this embodiment will be explained step by step with reference to FIG.

A) First, the photographer sets the sensitivity of the film he or she intends to use using the switch sense circuit 4 in FIG. (You may set it manually, but you may also use a means to read the DX.) 6 B) Point the camera at the subject, decide on framing and zooming, and perform photometry.

C) Using the photometric values measured in B), calculate and determine the aperture value and shutter speed value according to the program diagram of program AE.

D) Compare the calculated and determined shutter speed value with the focal length received through lens communication, and calculate the appropriate sensitization/desensitization multiple so that the shutter speed is within 1/2 of the focal length. .

E) Display the appropriate sensitization/desensitization multiple calculated in D) on the display member.

F) Manually determine whether or not to perform the sensitization/desensitization shown in E) using the switch sense path 4 in FIG.

G) If the photographer decides to use normal sensitization/desensitization in F) and manually inputs the switch sense circuit, the appropriate sensitization/desensitization multiple determined in D) will be applied to the sensitivity set in A). Set the ISO sensitivity multiplied by .

F) If the photographer decides not to use appropriate sensitization/desensitization in F) and manually inputs the switch sensing circuit, set the ISO sensitivity value set in A) as the shooting sensitivity.

Next, an example of calculating the appropriate sensitization/desensitization multiple in D) will be explained using FIG.

Let us assume that the photographer's planned film sensitivity is 15O100.

Furthermore, the photographing focal length is 200 mm. Program A
The diagram of E is shown in Figure 3, and the program diagram showing ζ is 4.
It is a 5° line diagram, and for EU12 or higher, when the brightness increases by one step, the aperture is closed down and the shutter speed is set to high speed.

Assume that the photographer points the lens at the aging subject and measures the light, and as a result, 17125 of 55.6 is calculated.

Here, if you increase the sensitivity by 1, the shutter speed will be 1/180.
Therefore, it does not exceed 1/200 of 1/focal length. Therefore, considering the double sensitivity, the shutter speed is calculated to be 1/250, which is within a means of exceeding 1/200 of the focal length. Therefore, the optimal sensitization factor here is 2.
It will be doubled.

Here, the IJ for the focal length, which is used as the criterion for determining the optimal sensitization multiple, is the generally said camera shake limit. It is desired that it be 1/200 or more.

[Effects of the Invention] By using the above embodiments, even beginners can take pictures with optimal sensitivity. Further, even if the photographer is unable to carry out sensitization/desensitization photography, a rough estimate can be easily obtained.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the camera, and FIG. 2 is a flowchart showing the operation of the microcomputer shown in FIG. 1. FIG. 3 is an explanatory diagram explaining the embodiment. 1...Microcomputer 2...Lens control circuit 3...Liquid crystal display circuit Figure 1 Camera Q-Follow, Figure 7

Claims (1)

[Scope of Claims] A camera having a built-in exposure meter, a means for determining an aperture value and a shutter speed based on the values of the exposure meter, a means for recognizing a focal length of a lens, and a display means, comprising: the built-in exposure meter; Depending on the photometered value, the focal length of the lens attached, the combination of aperture and shutter speed depending on the brightness, and the sensitivity of the photographic film, it is determined how many times the sensitivity is increased or decreased in the photometering situation. A camera characterized by displaying whether the feeling is appropriate.