Quote Originally Posted by Steve Axford View Post
If you have good focusing, I can't see why f4-5.6 would be such an impediment. Where would you use f2.8 for a 400mm? I don't do sports, but I do take wildlife and f2.8 gives you too little dof.
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Lance: perhaps you can chime in. I've never used a 400/2.8 but from my understanding, at this sort of FL you're always battling adequate shutter speeds and so the faster the better generally speaking but DOF is a lesser issue since if you can get close enough such that DOF becomes a big issue, then a shorter lens might suffice??