The Canon CN-E 50mm T1.3 L F Cine Lens is an EF-mount standard-width lens for Canon's C-series cinema cameras, for full-frame EOS DSLRs, and for any video-capable cameras that accept EF-mount lenses. Intended for the working professional, the EF Cinema Prime CN-E50mm T1.3 L F lens has markings on angled surfaces on both sides of the barrel, making it easy to read focus and aperture settings from behind or from either side of the camera. Focus markings can even be switched from standard labeling to metric. The control rings are engineered to maintain the proper amount of resistance with consistent operating torque. The aperture is a fast 1.3 and lets you get superior shots in low light. The diaphragm is made up of 11-blades that can produce impressive bokeh and beautiful circular highlights. The diaphragm ring is stepless, super-smooth and totally manual. The lens is based on Canon's EF 50mm f/1.2L and is optimized for cine-use with upgraded optics and coating and a completely redesigned mechanical construction. The lens features sharp optics capable of supporting even 4K recording quality.