The Sigma APO 120-400mm f/4.5-5.6 DG OS HSM is a telephoto lens that incorporates Sigma’s original Optical Stabiliser (OS) offering the equivalent of using a shutter speed approximately 4 stops faster. Three Special Low Dispersion (SLD) glass elements provide excellent correction for chromatic aberration. The super multi-layer lens coating reduces flare and ghosting. The minimum focusing distance of 150cm throughout the entire zoom range and a maximum magnification of 1:4.2 make it useful for close-up photography. The Hyper Sonic Motor (HSM) ensures a quiet and high-speed AF while providing full-time manual focus override.