Canon
EF 800mm f5.6L IS USM
Super telephoto lens
Despite the long 800mm focal length, a magnesium alloy construction makes this lens lighter then the 600mm f/4L lens, weighing less than 4.5kg.
The 800mm f/5.6 shares the same lightweight, weather-resistant construction as Canon's other IS super telephoto lenses, as well as their improved control layout, improved weight distribution, and mechanical manual focus. The IS Image Stabiliser mechanism allows the use of shutter speeds up to 4 times slower with no perceptible increase in image blur.
For optimum visual performance, the lens incorporates four types of special optical elements: aspherical elements to correct spherical aberrations, and refracting Fluorite, UD and Super UD (ultra-low dispersion) elements to eliminate chromatic aberrations.
This is not a lens for the feint-hearted, but if you're hoping to capture superlative images on assignment, the 800mm f/5.6 will bring you so close to the action, you'll feel like you can touch it.