a black level correcting device includes : an a / d converting section converting a result of subtracting a feedback signal from an input pixel signal into a pixel value to be output ; and a feedback controlling section generating the feedback signal and having a holding section , a feedback gain adjusting section , etc . the holding section clamps a maintaining level to the level of the feedback signal while pixel signals of ob pixels are output , and maintains and outputs the maintaining level while pixel signals of valid pixels are output . the feedback gain adjusting section multiplies the feedback signal by clamp accelerating gain in synchronization with starting readout of the pixel signals from the ob pixels . accordingly , clamp time of the holding section is shortened , enabling stabilization of the maintaining level at a convergence level before starting readout of the pixel signals from the valid pixels . consequently , a sag can be reduced .