ChrisBlaze wrote in post #2151031
so is the panning feature on the IS lens good for sports?
Honestly, I don't know as I don't own the 70-200. I have read and seen some test shots of panning on the IS that looks pretty good, but it's much better if some of the seasoned posters can enlighten you on that subject matter. 2.8 apeture is plenty fast for sports. If you look at the sidelines, those that shoot for a living all use 2.8 apeture lenses at football games. Anything faster would make focusing a nightmare since everyone is constantly on the move and the shallow DOF will not be able to keep things in focus long enough (as always, there's exceptions). If the lens is primarily for games and you can shoot from the sidelines with a steady tripod, IS is not necessary. If you do mostly hand-held, then it can be invaluable. So upon further reflection, I suppose 2.8 would be a good choice. 
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