Covering a versatile wide-angle range, the EF-S 10-22mm f/3.5-4.5 USM is designed for Canon EF-S-mount APS-C DSLRs, and provides a 16-35.2mm equivalent focal length range to suit working in a wide array of shooting conditions. Benefitting the flexible zoom range is a sophisticated optical design, which includes one Super-UD element and three aspherical elements to control chromatic and spherical aberrations, and a Super Spectra coating has been applied to limit flare and ghosting for improved contrast. Additionally, this lens sports a ring-type USM for quick and quiet autofocus performance and full-time manual focus override, and an internal focus design also quickens focusing speeds and maintains the overall lens length during operation. Wide-angle zoom is designed for APS-C-format Canon EF-S-mount DSLRs and provides a 16-35.2mm equivalent focal length range.One Super-Ultra-Low Dispersion glass element noticeably reduces color fringing and chromatic aberrations for high clarity and color fidelity.Three aspherical elements limit distortion and spherical aberration in order to realize greater sharpness and accurate rendering.Super Spectra coating has been applied to individual elements to minimize ghosting and flare for greater contrast and color neutrality when working in strong lighting conditions.A ring-type Ultrasonic Motor (USM), along with an internal focusing design, is employed to deliver fast, precise, and quiet autofocus performance as well as full-time manual focus override.Rounded six-blade diaphragm contributes to a pleasing out of focus quality that benefits the use of shallow depth of field and selective focus
