I know most people wouldn't think of this but couldn't you use a low power telescope or a travel telescope for a really nice, cheap, long telephoto lens. My friend he's into astronomy and he bought this 1300mm travel telescope for $250!! I came with the t-tube thingy so we only had to get a t-ring for and olympis mount (i own om-1 and an om-2) so I connected them and put in some velvia film in the camera. It was ammasing!!! It was really nice quality!! Even though it vinyeted or whatever you didn't really care. It was an Orion, Apex Maksutov-Cassgrain 102mm travel telescope. You only had to spend an extra 10 bucks for the t-ring for the mount of you camera you using on it. I was as good or better quality as my lenses!!! Once i get enough money im going to go out there and buy one insted of buying a $10,000 lens with the same focal length. Oh and also it was only about 8 or 10 inches long and only 5 inches in width!!