Mike Johnston said: > > I've been looking around lately for telephoto lenses 500mm or longer. With > > some modern computer design, glasses, and coatings, I was hoping to at least > > find decent but small aperture fixed lenses pretty cheap. Will I find that > > all the truly long telephotos either cost $5000, are mirror lenses, or are > > turkeys? > > > This is one of the huge advantages of digital IMHO. For instance, a 300mm > f/2.8 on a Canon D60 is the equivalent of a 480mm f/2.8 on 35mm. You get the > "teleconverter" factor without the f-stop penalty. > > A 400mm lens becomes a 640mm. Even a lowly, inexpensive 200mm becomes a > 320mm. Not too shabby.
Actually, I've been doing that with cropping! A little fox starts to look grainy on 1600 film when enlarged to 8x10 equivalent, but it still looks nicer. I've even been wondering at what point I'd come out ahead if I use a shorter lens with wider aperture and slower film. For instance, 500mm f/8 800ASA versus 200mm f/4 200ASA, or 135mm f/2.8 100ASA?
