1. An electronic still camera comprising: a photography mode selecting section allowing a photographer to select continuous photographing; an imaging section capturing an image of a subject; a photographic subject detecting section detecting a photographic subject based on a photographic image captured by the imaging section for every photograph; a non-delete area setting section setting a non-delete area including the detected photographic subject detected by the photographic subject detecting section; an area setting section dividing the photographic image into a plurality of blocks, and sorting blocks not being set as the non-delete area by the non-delete area setting section into an exclude area and a non-exclude area is an expansion to the non-delete area based on luminance information of each of the blocks not being set as the non-delete area; and a memory section storing an image inside the non-delete area and the non-exclude area as a photographic subject image.