| 摘要 |
PURPOSE:To pickup appropriately images in accordance with illuminance of a subject by comparing a level of a video signal obtained by an image pickup system with a prescribed level and interlocking a stroboscopic device with an image pickup start switch additionally installed on a main body so as to emit and operate the stroboscopic device when the video signal level is below the level concerned. CONSTITUTION:A luminance signal Y is also supplied to an average detection circuit 25, where an average of the luminance signals Y can be obtained in accordance with a clamp pulse from a synchronizing signal generator 4. When the average output is below a reference voltage 27, an output of a voltage comparator 26 is switched from ''0'' to ''1'' level, which causes an AND gate 22 to be opened. Consequently, when an image pickup start switch 20 is turned on, a stroboscopic emitting is executed by a pulse of a pulse generator 21. On the other hand, the output of the comparator 26 is also supplied to analog switches 28 and 29. When the output of the comparator 26 is at ''0'' level, the switching contact points of said switches are switched to a side (d), and the gains of GCAs (gain adjustment amplifiers) 11 and 12 are set by a voltage adjusted by volumes 30 and 31.
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