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The Sigma 800mm f5.6 EX HSM APO ultratelephoto lens incorporates two extraordinary low dispersion (ELD) glass elements, which help reduce chromatic aberration to the minimum limit. With a fast f5.6 aperture, this apochromatic lens also incorporates an internal focusing system to give you fast, responsive autofocus speed. The ultraquiet hyper-sonic motor (HSM) lets you shoot pictures without disturbing your subjects. Polarizing filters are extremely easy to use with this lens because of its rotary filter holder, located in the rear part of the lens barrel. The optic materials are lead- and arsenic-free ecological glass. This model is dedicated to Canon AF SLR cameras.

The Sigma Super Telephoto 800mm f/5.6 EX DG APO HSM Autofocus Lens for Canon EOS is a large aperture 800mm lens that explores the visual effects of a super telephoto to the limit. When it comes to nature and sports photography, often there is just no substitute for pure focal length. Wildlife is notoriously averse to close approach and in sporting events the photographer is often restricted to areas at some distance from the action. In other cases of surveillance or dangerous situations, a longer distance shot is much preferred. In this situation, the Sigma 800 lens is the perfect answer. Two ELD (Extraordinary Low Dispersion) glass elements provide optimum color correction and sharpness throughout the entire zoom range. A new multi-layer lens coating technology and lens design formula reduces flare and ghosting. Rear insertion 46mm filters with provision for easy rotation of polarizing filters. Compatible with the Sigma’s APO dedicated Tele converter 1.4x & 2x to provide additional focal length as a 1120mm F8 MF or 1600mm F11MF lens respectively.Features: Designed for use with full frame digital SLR cameras. May also be used with smaller APS-C size sensors with a corresponding effective increase in focal length to about 1200 with most camerasHSM (Hyper-Sonic Motor) ensures a quiet & high-speed auto focusJust over 20 inches long & weighs approximately 10.4poundsInner focusing system which enables responsive & fast auto focus speed & overall length does not change during focusing.Soft case, lens hood, circular PL filter are included. It is equipped with fixed tripod socket.