A thoroughly modern design that's optimized for select Canon EOS digital SLRs. Its angle of view is equivalent to a 96mm lens on a 35mm camera, with a floating optical system that can focus down to full life-size (1:1) magnification. Inner focusing, driven by a silent and powerful ring-type USM, means the lens' overall length never changes during focus. This lens is a wonderful multi-purpose lens that's equally at home shooting macro shots, portraits or available-light photos. Like all Canon EF-S Lenses, its use is restricted to the EOS 20D, 30D, 40D EOS Digital Rebel and EOS Digital Rebel XT cameras(as of September 2007).