1. An image capture apparatus comprising: a focus detection unit that detects a plurality of focus evaluation values by moving a focus lens within a driving range, the plurality of focus evaluation values indicating in-focus positions of a plurality of focus detection areas; a distance computation unit that computes subject distances of a plurality of subject areas included in a captured image based on the plurality of focus evaluation values; and a change detection unit that detects whether or not the captured image has changed, wherein when the change detection unit has detected a change in the captured image, the distance computation unit re-computes the subject distances of the plurality of subject areas by re-moving the focus lens, the driving range of the focus lens for re-computing the subject distances of the plurality of subject areas is determined in accordance with distribution of previously-computed subject distances of the plurality of subject areas, and the driving range of the focus lens for re-computing the subject distances of the plurality of subject areas includes in-focus positions corresponding to the previously-computed subject distances of the plurality of subject areas.