I used to have a FD 500mm f/4.5 which is nice but not as well corrected as modern glass. I got it for $750 which, too, is a bargain. > as long as you don't min

I used to have a FD 500mm f/4.5 which is nice but not as well corrected as modern glass. I got it for $750 which, too, is a bargain. > as long as you don't mind manual focus Given that the primary use case of large aperture telephoto lenses is sports and wildlife, fast autofocus is a killer feature. Moreover, modern computer optimization has managed to vastly lighten the weight and improve the weight distribution of the lens, not to mention impeccable image quality, which is why for many the $6000 is more than justified.