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Thinking of purchasing a used 500mm 4.5 non-IS to replace my 400mm 5.6. It would be used only on a tripod inside of a portable blind. My thinking is that it will do OK without the IS due to the blind keeping the wind off. Any downsides? I'm starting ...
On image tests my 400mm L 5.6 is performing significantly less sharp than my new 100-400mm lense. The only think I can think of that would have damaged the 400 was condensaton in the body from temperature changes. Shots are all tribod and cable trigg...