Abstract: An external sensor which may be detachably electrically connected to an electronic flash of the type having a flash duration control circuit for controlling the flash duration of a flash tube which flashes by discharging the electrical energy stored on a main capacitor, the external sensor including a light receiving unit which, in the automatic flash exposure mode, receives the light emitted from the flash and reflected back from a subject. In the automatic flash exposure mode in which the flash duration control circuit is activated in response to an interrupt signal from the light receiving unit, the external sensor selectively displays correct flash exposure data such as film speed, aperture and distance to a subject.

Abstract: A photographic flash device comprising a first mechanism for varying the angle of divergence of a flashed light and a second mechanism for varying the direction of the flashed light. The first variable mechanism is provided with a first body having a light source, a second body, a first slidable molding which has an optical panel to cover the front of the light source, a second slidable molding which surrounds the first slidable molding, and detent means which control slide movement of the first slidable molding and connects the first slidable molding with the first body. The second variable mechanism changes the direction of the flashed light from the light source by rotatably connecting the moldings to an additional body.