Canon has an EF 1200mm f/5.6L USM "available" on request. Legend has it there are only ten in the world and Sports Illustrated magazine owns two of them! If you have to ask the price you can't afford it! http://www.usa.canon.com/consumer/co...p;modelid=8178
Canon 2000mm F/11 mirror lens
Reflex-Nikkor 2000mm f/11 mirror lens
While these lenses were in the catalogs, they were usually special order items and were neither cheap or common! These were about the limit in photographic lenses as it became cheaper to attach your camera to an astronomical telescope.