To take a photograph in a sepia tone when luminance is high and to automatically switch it to ordinary color photographing when the luminance is low by providing a resin plate in which a photochromic element becoming brown when the luminance is high and becoming colorless when the luminance is low is mixed in an optical path of a photographing lens.

By properly mixing a photochromic element and a dyestuff, developed color and density are made different by the change of luminance. Then, a filter 14 is formed from a resin plate or a glass plate in which the photochromic element becoming brown when the luminance is high and decolorizing and becoming colorless when the luminance is low is mixed. A filter 14 made of the resin plate or the like in which the photochromic element is mixed is attached to an armor member 13 and provided in front of a photographing lens 11. Therefore, when the luminance is high, the filter 14 becomes the brown filter so that a photograph in a sepia tone is taken and when the luminance is low, the filter becomes colorless so that the ordinary color photographing is automatically performed.