The Canon EF-S 10-22mm f/3.5-4.5 USM Ultra-Wide Zoom Lens provides ultra wide-angle coverage to the EOS 20D, 30D, 40D, 50D and Digital Rebel SLRs. Equivalent to a 16-35mm zoom, it offers excellent performance and optics designed from the ground-up for digital SLR use. Three Aspherical lens elements, plus a Super-UD element, assure image quality. Its ring-type USM means fast and silent AF along with full-time manual focus. It focuses as close as 9.5 inches.