To experience the ultimate in wide-angle photography, the EF 11-24mm f/4L USM brings L-series construction and optics to the wide zoom lens. With an expansive wide-angle range, this is an ideal lens for landscapes, interior shots, and unique perspectives on subjects close and far. Its amazing optical design features Super UD and UD lenses that correct chromatic aberration. Four aspheric lens elements help to minimize distortion from the center of the image to the periphery and throughout the zoom range. A Subwavelength Coating (SWC) and Air Sphere Coating (ASC) significantly reduce flare and ghosting, while a 9-blade circular aperture diaphragm creates beautiful, blurred backgrounds. For silent and fast AF, it features a rear focus system and ring USM, and can be manually focused even when in AF mode. The EF 11-24mm f/4L USM is durable and rugged due to its highly dust resistant design, so it is prepared for shooting in different environments. It also has fluorine coatings on the front and rear elements for reducing smears and fingerprints. With a compact design, the EF 11-24mm f/4L USM is a must-have lens for photographers that demand excellent performance for truly expressive images anywhere.