To provide a photographing device which when photographing a moving image using a lens for photographing a still image by an illuminator for photographing a moving image and a single-lens reflex camera, properly controls exposure while saving a change of a diaphragm which is not for photographing a moving image originally.

The photographing device comprises: a gain control device with respect to an imaging element and output of the same; a photographic optical system and a diaphragm control device provided with a diaphragm mechanism; and an illuminator for photographing a moving image. In exposure control when photographing a moving image, gain control is performed with precedence over diaphragm control, and use of the illuminator under low luminance is given precedence over the diaphragm control and started after the start of the gain control, thereby properly controlling the exposure.