| 摘要 |
PURPOSE:To control an aperture value for flash photography by a selected aperture value, by selecting uniformly an opening-aperture-side value when the brightness of a subject is high and a small-aperture-side value as the brightness of a subject decreases alternatively. CONSTITUTION:Titled controller consists of a subject brightness photometric circuit 1, a comparing circuit 2 which compares its output with a reference value, an aperture value signal output circuit 3 which outputs two kinds of aperture value, a selecting circuit 4 which outputs one of two kinds of aperture signal to an aperture control part CA and an aperture value display part DPA according to the output of the comparator 2, a flash light amount control circuit 5 which outputs a flash lighting stop signal, etc. For this purpose, a decision on the brightness level of a subject is made, an aperture value corresponding to it is selected, and an aperture for flash photography is controlled on the basis of the aperture value, so a focus adjustment and an adjustment to a proper aperture opening to the quantity of flash light are made automatically to eliminate the need for a photographer's judgment of the aperture value, so that flash photography is performed through simple operation. |
