1. An image processing device comprising: a motion vector detection portion that performs comparison of a substantially spherical photographic subject such that, among a plurality of captured images including the photographic subject, an image as a processing target and another image as a comparison target are compared using each of the plurality of captured images as the processing target, and which detects a motion vector of a whole three-dimensional spherical model with respect to the processing target; a motion compensation portion that performs motion compensation on the processing target, based on the motion vector of each of the plurality of captured images that is detected by the motion vector detection portion; and a synthesis portion that synthesizes each of the captured images that are obtained as a result of the motion compensation performed by the motion compensation portion.