Upon depression of a release button, pre-shooting is performed before regular shooting. In the pre-shooting, flash of a predetermined amount is emitted and exposure of an image sensor is performed. A shooting frame is divided into small areas. As to each of the small areas, subject brightness of pre-emission and subject brightness of non-emission are detected to calculate a difference between them. The small area having the maximum difference is selected as a main-subject area. The brightness of the non-emission of the selected small area, which is the brightness of an ambient light applied to the main subject, is set as reference brightness. A correction amount of the flash amount of the regular shooting corresponding to the reference brightness is derived with reference to an LUT. In the regular shooting, regular emission is performed during a regular-emission time corresponding to the collected flash amount.