Originally posted by Marc Sabatella Either you *need* f/2.8 and are willing to sacrifice 100mm at the long end, spend twice as much money, and carry around a lens three times heavier to get it, or else you're better off with the 55-300.
The 60-250/4 doens't even give you f/2.8, although it does give you great image quality and f/4 wihich is also worth something to some people - but it's nowhere *near* $500, so it wouldn't be in contention.
The more I think about it, the more I think I'll be disappointed if I don't go with the f2.8, particularly for the astrophotography side of things. I really don't think I will get away with anything less for that.
It seems there are a few different versions of the Sigma 70-200mm's - I have yet to work out which is best, but I have come to the conclusion that the macro version isn't really what I'm after. I really want to have a sharp image even at 200mm and as wide as possible.
The gap between 55 - 70 won't be too much of an issue, I don't think.