The Sigma 150-600mm f/5-6.3 DG OS HSM is a Contemporary-series telephoto zoom characterized by its sophisticated optics and flexible handling. One FLD element and three SLD elements are used to reduce espandi... color fringing and chromatic aberrations throughout the zoom range and a Super Multi-Coating also helps to suppress flare and ghosting for improved contrast and color accuracy when working in strong lighting conditions. Balancing the optical design, this lens also features a Hyper Sonic Motor, which provides especially fast and quiet autofocus performance as well as full-time manual focus override.