Olympus M.Zuiko Digital ED 8mm f1.8 Fisheye PRO Lens 17 elements in 15 groups reduces aberrations, 3 Super ED lenses, 2 ED lenses diminish peripheral chromatic aberrations 180 degree angle of view ZERO lens coating effectively minimizes ghosting and flaring Silent auto focus for Movie-Still compatibility Minimum working distance of 2.5cm from the end of the lens