The samyang 50mm f12 as umc cs is a manual focus lens for mirrorless cameras with aps c sensor sizes the lens features a bright f12 aperture with impressive bokeh and incorporates nine lenses in seven groups with two glass aspherical lenses asp and ultra multi coating umc to deliver outstanding image quality this lens is great for portraiture travel and capturing the true atmosphere of a scene even in dimly lit environments without the need for flash or a tripod