| 摘要 |
PROBLEM TO BE SOLVED: To correctly grasp lens diaphragm value information by storing the correlation of a control voltage with a lens diaphragm value, controlling a diaphragm means in the case of photographing to keep the output value of an image pickup unit constant, monitoring the control voltage of a diaphragm control means with a diaphragm detecting means and changing the parameter of signal processing when the diaphragm value departs from a prescribed range. SOLUTION: A diaphragm control circuit 17 controls an diaphragm mechanism 13 to keep the output of the image pickup unit 15 constant in the case of photographing by a video camera and the diaphragm detecting circuit 2 always monitors the control voltage of the circuit 17 while executing the control. Then the diaphragm value corresponding to the control voltage stored in a storage element 1 is read from the control voltage to be detected and the diaphragm value is transmitted to a camera control circuit 3. A camera control circuit 3 gives an indication to a signal processing circuit 16 to decrease shutter speed or to increase gain when the diaphragm value takes the min. value. When it becomes maximum, the change of the signal processing parameter is indicated to the camera control circuit 3.
|
