Capture excellent photos with the Electronic Flash EF 500 DG from Sigma. It is designed to work with both AF 35 mm SLR and Digital SLR cameras. The projection angle of the flashlight is set automatically to match the lens' focal length ranging from 28 mm wide-angle to 105 mm medium-telephoto. It incorporates a built-in diffuser that expands the angle of illumination down to that of 17 mm lens. In addition, it enables full automatic flash photography by TTL automatic flash exposure control. For b