1. An image processing, apparatus comprising: a controller configured to select either of a first tracking system that tracks a subject by moving an optical unit in a direction different from an optical axis, or a second tracking system that tracks the subject electronically such that the subject is within a vicinity of the center of a captured image, as a tracking system used for tracking the subject so that the subject is kept within a predetermined angle of the captured image, wherein the controller selects the second tracking system as the tracking system used at a start of the tracking of the subject when the subject is positioned within a captured field angle, a zoom position is at a wide side, and a motion vector is less than a predetermined amount.