New Sigma APO 50-500mm F4.5-6.3 DG OS HSM. This is a 10x high zoom ratio ultra telephoto zoom lens incorporating Sigma's original Optical Stabilizer function. This lens covers a wide range of focal lengths from 50mm to 500mm ultra telephoto. The OS (Optical Stabilizer) function offers the use of shutter speeds approximately 4 stops slower than would otherwise be possible. Four SLD (Special Low Dispersion) glass elements provide excellent correction of color aberration. The Super Multi-Layer Coating reduces flare and ghost and ensures high image quality throughout the entire zoom range. This lens has a maximum magnification ratio of 1:3.1 (at the focal length of 200mm) making it ideal for close-up photography. This lens incorporates HSM (Hyper Sonic Motor), ensuring quiet and high speed AF as well as full-time manual focus capability. The addition of the optional 1.4x EX DG or 2x EX DG APO Tele Converters produce a 70-700mm F6.3-8 or a 100-1000mm F9-12.6 MF zoom lens respectively. This lens is equipped with a Petal-type hood to block out extraneous light. The filter size of this lens is 95mm and the lens is supplied with a step down ring enabling digital cameras with an APS-C size image sensor to use an 86mm filter. *For Nikon and Canon mounts, Optical Stabilizer (OS) function will not work with film SLR cameras except Nikon F6 and Canon EOS-1V.