To provide an imaging apparatus having high-speed focusing characteristic and providing high-quality image output as well in an area where a photographing area is wide.

This imaging apparatus is equipped with a plurality of photoelectric conversion parts, a control means capable of switching a first output mode in which the signals of two or more photoelectric conversion parts are added and read out the result of addition and a second output mode in which the signal of the photoelectric conversion part is independently read out, a storage means storing a first correction value to correct the non-uniformity of an output signal by the first output mode and a second correction value to correct the non-uniformity of an output signal by the second output mode, and a correction means performing correction to the output signal by the first output mode based on the first correction value and performing correction to the output signal by the second output mode based on the second correction value.