Canon EF 800mm f/5.6L IS USM US$13,999

Canon unveiled this L Series lens in June 2008. The magnesium lens barrel contains several fluorite lenses and an extra-low dispersion (ED) lens, driven by the USM-propelled internal focusing system. This lens is compatible with Canon EF extenders.

This is also the most expensive lens in the current Canon catalogue, though still much cheaper than Nikon's NIKKOR 800mm f/5.6. Nonetheless, for most people, Canon's 400mm f/2.8 IS or 600mm f/4 IS would be the more flexible option since much of the 800mm's work could be realized by an extender. There is no way of reducing the focal length on the 800mm.