1. An imaging apparatus comprising: a plurality of imaging units that take subject images from different viewpoints; a vibration detection unit that detects each vibration of the imaging units; and a vibration correction unit that corrects the vibration of the subject image taken by each imaging unit based on the vibration of each imaging unit detected by the vibration detection unit, the imaging apparatus comprising: a size determination unit that determines a cut-out size for cutting out an image for output from an image acquired from each of the plurality of imaging units, the size determination unit determining the cut-out size with a predetermined aspect ratio common to a plurality of images acquired from each of the plurality of imaging units based on a possible area in a minimum size among sizes of possible areas around an initial optical axis center included in areas common to prescribed imaging areas based on the initial optical axis center before each vibration correction by the plurality of imaging units and imaging areas after each vibration correction by the plurality of imaging units; and a cut-out unit that cuts out the image for output from each of the plurality of images in the common cut-out size determined by the size determination unit based on the initial optical axis center before each vibration correction by the plurality of imaging units.