Broaden your perspective with the Canon EF 16-35mm ultra-wide-angle zoom lens. Specifically designed for improved edge-to-edge image quality that meets the strict requirements of professional and high-end amateur photographers alike, the lens lets you bring more area into focus while providing greater depth of field. The lens features three high-precision aspherical lens elements--ground, replica, and GMo--that produce even better image quality than the original Canon EF 16-35mm USM lens. The circular aperture, meanwhile, produces a beautiful and natural background blur when shooting at wider apertures. Other details include internal focusing, a ring-type ultra-sonic monitor (USM), and new AF algorithms for fast and quiet autofocusing.