Title:
MOVIE CAMERA
Document Type and Number:
Japanese Patent JPS5415742
Kind Code:
A
Abstract:
A motor driving the shutter of a motion-picture camera is intermittently energizable under the control of two time-constant networks triggering respective pulse generators of the one-shot type, the first time-constant network including a photoresistor to measure an exposure interval dependent upon luminous intensity, the second time-constant network being adjustable to establish a selected recurrence period. With the shutter arrested in an unblocking position at the start of an operating cycle, which coincides with the beginning of an exposure interval, a pulse from the first generator releases the shutter for movement into a blocking position until a pulse from the second generator restarts the cycle by letting the shutter return to its unblocking position. If, however, illumination is so low that the exposure interval outlasts the preset recurrence period, the shutter remains open until the first pulse generator signals the end of the exposure interval whereupon the cycle is immediately restarted; this latter condition, involving the lengthening of a cycle, can be indicated to the user by a light signal.
Inventors:
FURANTSU DEERIHI
Application Number:
JP4309078A
Publication Date:
February 05, 1979
Filing Date:
April 12, 1978
Export Citation:
Assignee:
BOLEX INT SA
International Classes:
G03B7/083; G03B7/085; G03B15/08; G03B19/18; (IPC1-7): G03B7/08; G03B19/18