The 18-200mm f/3.5-6.3 DC Macro OS HSM Lens For Sigma Digital Cameras from Sigma is an all-in-one lens covering an 11x zoom from wide-angle to telephoto, with a 35mm equivalent focal length of 29-320mm. An optical stabilizer (OS) system is built into the lens, which reduces the appearance of camera shake. This can be especially helpful when shooting at long focal lengths or up-close macro shots. OS also allows you to use slightly longer shutter speeds, making it possible to shoot hand-held in low-light conditions. The built-in Hyper Sonic Motor delivers quick and quiet autofocus.,,The 18-200mm's optical design incorporates double-sided aspherical lenses which enable this extended super-zoom lens to be housed in a compact and lightweight construction. Special Low Dispersion (SLD) glass, correct chromatic aberrations, and Super Multi-Layer Coating reduces flare and ghosting, to provide sharp, high contrast images even in backlit conditions.