Canon EF 800mm f/5.6L IS USM

This is the longest telephoto lens among Canon's lineup, and a terrific choice for any long-distance application-outdoor sports, wildlife, news photojournalism, and so on. It's actually lighter than Canon's EF 600mm f/4L IS lens, weighing just under 10 lbs. It uses a refined optical design, with two fluorite lens elements, one UD element, and one Super-UD-glass element, for outstanding correction of color fringing and superb contrast and sharpness. This super-telephoto lens uses magnesium-alloy barrel construction to enhance its light weight, and has weather-resistant gaskets throughout for use in harsh conditions. It's compatible with both the EF 1.4x II and 2x II tele extenders for even more reach: EOS cameras with 45 AF points will continue to provide autofocus at the center AF point when the lens is used with the 1.4x extender. Finally, it's image stabilized, providing up to 4 stops of correction for camera shake. This makes it even more practical in many situations.

The EF 800mm f/5.6L IS USM is a professional L series lens released June 2008. This lens is constructed with a magnesium alloy body and mount and with plastic extremities and switches. Features of this lens are: a wide rubber focus ring that is damped, a focus distance window, the ability to limit the focus range, a focus-preset mechanism, an image stabilizer that is effective up to four stops and is tripod sensing, an AF stop switch, and weather sealing. A maximum aperture of f/5.6 gives this lens the ability to create depth of field effects. The optical construction of this lens contains two fluorite lens elements, and "Super UD" (Ultra low dispersion) and UD Lens elements. This lens uses an inner focusing system powered by a ring type USM motor. This lens is compatible with the Canon Extender EF teleconverters.