Packed with the latest technology from sigma and smaller than its predecessor the sigma 70 200mm f28 ex dg os hsm lens is the second generation of the large aperture 70 200mm f28 telephoto zoom the lens now incorporates optical stabilisation os which helps achieve blur free shots even at maximum zoom and its fast f28 aperture is extremely useful in low light or when shooting fast moving subjects where a higher shutter speed demands maximum light gathering the hsm hyper sonic motor