The EF-S 17-55mm f/2.8 IS USM from Canon pairs the 27.2-88mm equivalent focal length range with a bright f/2.8 constant maximum aperture. Benefitting this design is a sophisticated optical layout, which includes both Ultra-Low Dispersion glass and aspherical elements to significantly reduce chromatic and spherical aberrations for improved clarity and sharpness throughout the zoom range. this 17-55mm is also characterized by its advanced three stop-effective Image Stabilizer system to minimize the appearance of camera shake. Three aspherical elements minimize spherical aberrations and distortions for improved sharpness and accurate rendering. An Optical Image Stabilizer helps to minimize the appearance of camera shake by up to three shutter speed stops to better enable working in low-light conditions and with slower shutter speeds.
Canon EF-S 17-55mm F/2.8 IS USM Specs