Spanning a wide-angle to telephoto range, the EF-S 17-85mm f/4-5.6 IS USM from Canon is a 27.2-136mm-equivalent zoom designed for EF-S-mount DSLRs. This reach is complemented by an optical design featuring one dual-sided aspherical element, which helps to minimize distortion and spherical aberrations in order to realize greater sharpness and clarity. A Super Spectra coating has also been applied that reduces flare and ghosting for improved contrast and color accuracy. The lens also features an Optical Image Stabilizer, which minimizes the appearance of camera shake by three stops to better enable shooting handheld in difficult lighting conditions. Additionally, a ring-type Ultrasonic Motor is featured, too, which affords quick, quiet autofocus performance along with full-time manual focus override.