1. A camera system, comprising: an imaging optical system configured to form an optical image of a subject; an imaging component configured to convert the optical image into an image signal and successively acquiring images of the subject based on a photography condition; a display component having first and second display regions that allow a plurality of the images acquired by the imaging component to be displayed side by side; a condition adjustment component configured to adjust the photography condition to a first photography condition in a first period; and a display control component configured to control the display component to display at least part of a first image acquired by the imaging component under the first photography condition as a reference image in the first display region and to display at least part of a second image acquired by the imaging component at a different timing from that of the first image as a comparative image in the second display region, wherein the display control component is arranged to enlarge a part of the reference image in the first display region more than another portion of the reference image, and is arranged to enlarge a part of the comparative image in the second display region more than another portion of the comparative image, wherein the positional relationship of the part of the reference image with respect to the first image is the same as the positional relationship of the part of the comparative image with respect to the second image.