1. An image processing apparatus comprising: an obtaining unit which obtains an image signal output by image capturing; a separation unit which generates, from the image signal obtained by the obtaining unit, a plurality of image signals each having a different resolution, wherein the plurality of image signals include a first age signal and a second image signal having a rawer resolution than the first image signal; an image processing unit which applies predetermined image processing to each of the plurality of image signals generated by the separation unit; a generation unit which generates an image signal for saving using the first and second image signals to which the image processing unit have applied the predetermined image processing, and generates an image signal for display using the second image signal to which the image processing unit has applied the predetermined image processing and without using the first image signal.