Particularly suited for the demands of photojournalism, this high-performance, ultra-wideangle lens is the perfect complement to Nikon's Professional Digital SLR D1. [The lens's effective coverage is equivalent to using a 21mm on 35mm (135) film format.] Extra-low Dispersion (ED) glass and aspherical lens elements deliver superior optical performance. Key Features Hybrid aspherical lens elements and ED glass elements for high-resolution and high-contrast images. RF (rear focus) system for superior optical performance. Rectilinear design provides streight-line subject rendition. Built-in flower type lens hood.