Canon EF 11-24mm f/4L USM Lens L-series ultra-wide zoom lens with an impressive 11mm starting focal length Focal Length & Maximum Aperture: 1124mm f/4, Closest Focusing Distance : 11 in. / 0.28m New optical design and the use of one Super UD element and one UD lens element Subwavelength Coating (SWC) and Air Sphere Coating (ASC), Inner focusing, ring USM, a high-speed CPU and optimized AF algorithms Full-time manual focus allows manual focus adjustment while in AF Mode