1. An image pickup apparatus comprising: an image pickup device that shoots a subject to acquire image data on the subject; a focus lens; a controller that acquires a focusing condition of said focus lens for every position of said focus lens based on an output of said image pickup device, and controllably moves said focus lens to cause said image pickup device to perform automatic focusing, based on the acquired focusing condition; a face information detecting device that detects information on a face of the subject from the acquired image data; a distance estimating device that estimates a subject distance from said image pickup device to the subject based on the detected information on the face; and a depth-of-field calculating device that calculates a depth of field, wherein said controller performs a first detecting operation of determining a focusing condition of the focus lens by moving the focus lens over a predetermined range of movement of the focus lens when said face information detecting device does not detect the information on the face of the subject from the acquired image data, and performs a second detecting operation of determining a focusing condition of the focus lens by moving the focus lens over a narrower range of movement of the focus lens than the predetermined range of movement of the focus lens in accordance with the calculated depth of field, said narrower range including a position of the focus lens corresponding to the estimated subject distance, when said face information detecting device detects the information on the face of the subject from the acquired image data.