Camera system including exposure mode data back and flash accessories

• US 4,935,766 A
• Filed: 03/24/1989
• Issued: 06/19/1990
• Est. Priority Date: 01/21/1985
• Status: Expired due to Term

• Current Assignee: Minolta Camera Kabushiki Kaisha
• Original Assignee: Minolta Camera Kabushiki Kaisha
• Inventors: Yoshida, Tadahiro, Nakai, Masaaki, Taniguchi, Nobuyuki, Omaki, Takanobu, Nakasa, Masayuki, Kikukawa, Yoshiiku, Kitaura, Mashio
• Primary Examiner(s): PERKEY, WILLIAM B
• Application Number:
  US07/328,551
• Time in Patent Office: 452 Days
• Field of Search: 354/412, 354/413, 354/442
• US Class Current: 396/166
• CPC Class Codes: G03B 7/091 Digital circuits

Abstract

A camera system including a camera body and a camera accessory attachable to the camera body, such as an interchangeable back lid, an interchangeable lens, a flash device and so on, is disclosed. In the system, a plurality of circuits provided in a plurality of camera accessories are controlled by a microcomputer provided in the camera body. Data transmission between the microcomputer and the circuits uses a serial data bus and synchronizing clock line connected therebetween. The circuit to receive the data sent from the microcomputer, or the circuit which should send the data to the microcomputer, are selected by the microcomputer through chip select lines provided between the microcomputer and each circuit. The camera system is capable of coordinating flash mode and a bracket exposure mode. When the bracket mode is set, an exposure value for obtaining a proper exposure condition, a value for obtaining an over exposure condition by a predetermined exposure amount, and a value for obtaining an under exposure condition by a predetermined amount are each calculated for serially exposing a plurality of frames. Serial exposure of the frames is interrupted when a flash photographing mode is discriminated.

Claims

1. An exposure control device of a camera, comprising:

means for setting a bracket mode;

means, when the bracket mode is set, for calculating a first exposure value for obtaining a proper exposure condition, a second exposure value for obtaining an over exposure condition by a predetermined exposure amount from the proper exposure condition, and a third exposure value for obtaining an under exposure condition by a predetermined exposure amount from the proper exposure condition;

means, when the bracket mode is set, for serially exposing a plurality of frames in accordance with the first, second, and third exposure values, respectively;

means for discriminating which mode is selected among a flash photographing mode in which an exposure will be performed using a flash light illumination, and a normal photographing mode in which an exposure will be performed without using a flash light illumination; and

means for controlling the exposing means to permit the exposure operation of the exposing means under the bracket mode when the normal photographing mode is discriminated by the discriminating means, and to interrupt the exposure operation of the exposing means under the bracket mode when the flash photographing mode is discriminated by the discriminating means.

2. An exposure control device as claimed in claim 1, wherein the calculating means includes means for determining a shifting amount, and means for calculating the second exposure value for obtaining an over exposure condition by the shifting amount from the proper exposure condition and the third exposure value for obtaining an under exposure condition by the shifting amount from the proper exposure condition.