| 摘要 |
PURPOSE:To utilize more effectively exposure range data on a film cartridge as the alarm control of a camera by performing alarm display when an exposure control factor calculated by exposure arithmetic exceeds a controllable limit signal. CONSTITUTION:A subtracting circuit SU1 calculates an exposure time Tva1 by; inputting a photometric output Bv-Avo+Sv and a set stop-down stage number signal Av-Avo where Bv, Avo, Sv, and Av are subject brightness, an open-aperture value, film sesitivity, and the set aperture value. Terminals J11 and J12 of a data output block DO are connected to a decoder DE, which outputs a plus-side range signal EH and a minus-side range signal EL. A constant voltage source EC outputs a signal Tvc for a long-side limit exposure time with which no camera blur occurs. Consequently, when Tva1 is outputted while Tvc-EL> Tva1, the output of an AND circuit AN2 goes up to ''High'' and a camera blur alarm circuit DH generates an alarm. |
