Patent attributes
In an electronic camera, an exposure amount S ( 1/2000 sec.), an exposure amount M ( 1/250 sec.) and an exposure amount L ( 1/30 sec.) are set in vertically synchronous signal timing directly before the fourth frame, the fifth frame, and the sixth frame. In the frame directly following that setting, exposure is performed corresponding to that exposure amount. The signal levels obtained from the three exposure amounts are compared in the eighth frame, and an added value α is added to the shutter time in which the signal level obtained is closest to the optimum signal level. This time is set in vertically synchronous signal timing directly before the ninth frame. In the ninth frame, exposure is performed corresponding to this setting. In the tenth frame, the signal is readout according to this exposure. In the eleventh frame, the signal calculation is performed. The processing is repeated in the same way thereafter and the optimum exposure amount is determined.
