When I browse through some of the postings about lenses, I find that there seems to be a liking toward the 85mm prime. I've heard they make great portrait lenses giving their short telephoto length so one can get close but not right in the subjects face. With that and the fact that the 1ds() and 5d() are full frame cameras, does one still get an 85mm for the APS-C format cameras or does one get the 50mm? With the crop factor of 1.6 on the APS-C, that 85mm now becomes a 135mm (give or take) and the 50 becomes a 80mm. I realize that this could all be subjective, but I am sure there are several schools of thought regarding this perspective. For me, since I have both types of formats in my 1ds and 20d, I would probably own one of each just so I was covered either way. Currently I do not own any primes except for my Nikon film cameras. Thoughts? Comments?