Reflex Lenses Reflex-Nikkors employ the same magnification technology as powerful mirror-reflex telescopes. This makes them ideal for creating dramatic frame-filling photographs of far-off subjects. And because reflex lenses essentially fold the light path, they're smaller and lighter than conventional lenses with equivalent focal lengths. Ideal for photographing shy or dangerous animals. Powerful frame-filling 20X magnification. Outstanding picture quality. Very compact and light for its long focal length. Accepts 39mm bayonet filters. Built-in lens hood.