50/1.4 vs 85 f1.8
I would always choose the 85/1.8 because:
a) it is a much better lense with only a marginally worse aperture
b) you can buy a 50/1.8 for so little money to cover that focal length, that it seems like a sin not to have one! The 50/1.8 is also so light, that you can always carry it along. Unless you really need to shoot at 1/4, why pay the extra over the 50/1.8?
c) I find that I nearly always want a longer focal length than 50, even on a 1.6 factor camera, unless I'm doing group photos or landscapes.
John



