1. An apparatus for setting an exposure time, the apparatus comprising: a section setting module which sets plural luminance sections based on a determined luminance distribution of an input image; an image division module which divides the input image into two or more regions; a region classification module which classifies the regions into the luminance sections based on respective analyses of luminance of each of the regions identifying which of the luminance sections each region should be classified into; and an exposure-time setting module which sets an exposure time for each of the regions with reference to a target luminance value of each respective region, the target luminance value being set based on the results of the classification performed by the region classification module, wherein the exposure time is set to obtain plural images with different exposure times, the plural images being synthesized.