Camera having automatic and manual exposure-time determination

摘要

A camera which is capable of automatically determining exposure time and which is also capable of providing for manual determination of exposure time either in a manual-mechanical range of exposure times or in a mechanical-electrical range of exposure times. The automatic exposure-time determining structure includes an electromagnet which is energized when the shutter is opened and which is deenergized to bring about closing of the shutter so as to terminate an exposure. In the electrical circuitry which is connected to this electromagnet there are a pair of parallel-connected switches one of which is an automatic switch for providing for energizing of the electromagnet whenever the shutter has opened to start an exposure while the other switch is a manual switch for preventing energizing of the electromagnet only in the manual-mechanical range of exposures so that electrical energy is not needlessly consumed and the operations are not interfered with by energizing of the electromagnet during operations with manual determination of exposure in the manual-mechanical exposure time range. However, during automatic determination of exposure or during manual determination in the mechanical-electrical range the mechanical switch has no influence on the electromagnet.