Every once in a while I get a wild hair and want to swap out lenses. This year it's worse than usual. I have been using my 20-35L almost exclusively on a 30D and have pretty much well fallen in love with the lens. I also got a 55-250 IS that is surprisingly good. What this has meant is that my Sigma 50 and Canon 85 1.8 have been sitting around collecting dust. I also have a 17-35L that just sits around too. I was thinking about consolidating this year by selling the 17-35, 50 1.4 and 85 1.8 and buying a 24-70L. I also have a 5Dc which this focal length would be perfect for.
Maybe I am getting lazy in my old age but I don't want to be constantly swapping out lenses anymore. The 20-35 is great and I know I will get stellar results. Will the 24-70 deliver as well as the 20-35 is the big question? Is the 24-70 a back breaker of the lens that is just too big to carry around comfortably. Will the image quality come close to that of the 50 or 85 at f2.8? I'm just not sure on any of these things.
.

