Image pickup system, image pickup apparatus and sensitivity control method for correcting sensitivity of an image pickup apparatus using an electron multiplying-charge coupled device

An image pickup apparatus for outputting an image signal comprising:

• an electron multiplying charge coupled device for obtaining an electric signal by performing a photoelectric conversion on an incident light and carrying out an electron multiplication on the electric signal at an electron multiplication factor to generate a multiplied electric signal to be converted into the image signal;
• a memory unit for storing a correction coefficient acquired from outside the image pickup apparatus based on the image signal output from the image pickup apparatus;
• a sensitivity setting unit for setting a sensitivity value for the image signal;
• and
• a control unit for controlling the electron multiplying-charge coupled device based on a value obtained by multiplying the sensitivity value by the correction coefficient stored in the memory unit.

A sensitivity control method comprising:

• measuring electron multiplication properties of an image signal output from an electron multiplication image pickup apparatus;
• setting a sensitivity value for the image signal;
• correcting the sensitivity value by multiplying the sensitivity value by a correction coefficient calculated outside the electron multiplication image pickup apparatus based on the measured electron multiplication properties of the image signal;
• and
• controlling the electron multiplication image pickup apparatus based on the corrected sensitivity value.