We know shutter, had you listened to slow door? The flyer that we see slow door film today ~ (the picture comes from Oriental IC)? The shutter speed that slow door points to camera namely moves 1/30 second - 1/60 second. | | | (the picture comes from Oriental IC)Use slow fast shutter moves at the same time camera is a kind more require a skill film gimmick, say normally shake for " pat " or " is chased after pat " . (the picture comes from Oriental IC)