1. An image capturing apparatus comprising: an image sensor in which a plurality of pixels are arranged two-dimensionally; and at least one processor; and a memory storing instructions which cause the at least one processor to perform operations of a control unit, wherein: the control unit is configured to control a band gap of the pixels of the image sensor, and wherein the control unit, in a case where defective pixel detection processing is performed on the image sensor, controls the band gap so as to be smaller than in a case where normal image capture is performed.