The Sigma 70-200mm f/2.8 APO EX DG OS HSM (Sigma part# 589-101 for Canon EF Mount DSLRs) is a large aperture telephoto zoom lens that now incorporates Sigma’s OS (Optical Stablization) anti-shake system. A 70-200mm focal length range lens with good light gathering capability is widely regarded as one of the most important tools for serious photographers to own (along with a standards lens and a mid-range zoom). It's exceptionally versatile as an all-around lens perfect for photojournalists, wedding photographers, portraits, landscapes, sports action and more. This version of the Sigma 70-200mm is well regarded for its outstanding image quality, reasonable weight and ease of operation.
Sigma has included two FLD (performance equivalent to fluorite glass) glass elements along with three SLD glass elements in a state of the art optical design that provides excellent correction of aberrations. Sigma's Super Multi-Layer lens coating also reduces flare ghosting and maximizes image contrast for top quality results like pros expect. The bright f/2.8 maximum aperture aperture is extremely useful and important in low light environments or when shooting fast moving situations where higher shutter speed require more light thru the lens; the rounded 9 blade diaphragm also helps create smooth attractive blur in the out of focus area of images. Even with glass and OS additions, Sigma has managed to make the lens more compact than its predecessor, measuring only 7.8 inches in length.
Auto Focusing performance is fast and responsive thanks to the lens' HSM (HyperSonic Motor) system with full time manual focus override. The minimum focusing distance is 55.1 inches throughout the entire zoom range and the maximum magnification ratio is 1:8 (unaugmented).
Available accessories include: petal style Lens Hood, APS-C format Hood Adapter (extends shade), 77mm filters, Sigma teleconverters.