An image pickup system includes an image pickup device including an image pickup section, a first amplifier circuit capable of amplifying a video signal for each field, and a communication circuit configured to acquire a set gain of the first amplifier circuit, a second amplifier circuit configured to amplify the video signal outputted from the image pickup device, and a processor. According to a result of a detection indicating that the video signal is not amplified by the set gain in the first amplifier circuit, a correction gain to be set in the second amplifier circuit is calculated.