That's only partly true I think. Unlike the days they were still manufactured, most SLR bodies are now perceived as little more than a light box to hang a lens on, with prices to match. Although I own a variety of focal length lenses, 90% of shooting is taken care of by a wide and a standard, and as I said in the original post, 50mm has come to dominate. It's normal for me to dedicate two camera manufacturer's bodies to different lengths, for example a 24mm Canon FD and a 50mm Nikon. It also depends on what the subject is and how much value I attach to a lens financially, or personally. If I know a camera is in for what most people consider abuse (lying on a beach, being dropped or banged on solid objects, balanced on a rock, etc) a Nikkormat and a pre-AI lens is what I'd typically grab. If I need point and shoot characteristics, one of the A-series Canons, probably an AV-1 is what I'd use.
Originally Posted by jjphoto
I agree with what you say about 50mm lenses being more equal IQ wise than most other focal lengths. I usually test mine on a DSLR body at 100% magnification which picks out any discrepancies, especially in the corners, but at a couple of stops down there's little to separate most. Interestingly, I find shooting on movie to be a great way of defining the character of a lens, as the moving image resolves the look of a lens in a way stills rarely do. It's also a good way of seeing whether any lens defects translate into aberrations in use, as flare can be seen increasing, or not, with each subsequent frame.