Rokinon's MF 14mm F2.8 SERIES II Full Frame Ultra Wide Angle Lens for Nikon features weather sealing, an aperture de-click switch for smooth and silent operation during video, a rubberized micro pattern focusing grip, and a nine blade circular aperture for greater bokeh. In addition, the focusing control action has been modified with a smoother, perfectly damped long throw for precise follow focus when shooting video. Astrophotographers will also enjoy the 14mm's distinctive focus lock feature to maintain precise focus at infinity during long exposures.