PURPOSE: To set the photographic sensitivity of even a long-sized film having no photographic sensitivity information, by detecting a film back being mounted and stopping the transmission of photogaphic sensitivity information from an automatic setting device to an exposure control circuit, and sending photographic sensitivity information from a manual photographic sensitivity setting device instead.
CONSTITUTION: When the film back 2 is attached to a camera 1, a control circuit shown in a figure is constituted. The camera 1 is provided with a light source 29, automatic film sensitivity setting device 30, exposure control circuit 31, shutter release film advance control circuit 32, and switches 26 and 27. When the film back 2 is mounted on the camera 1, the switch 26 is changed over to the side of a terminal (c), so the film sensitivity information is inputted through a variable resistor 13 provided to the film back 2 and while film sensitivity setting is not performed from the side of the film back 2, the switch 2 is off, disallowing shutter release through the shutter release film advance control circuit 32.
YONEDA OSAMU
OKABE NOBUO
