So I've been shooting a bit of hockey in the past month or so, and just recently I've used 2 bodies, one with a 300 2.8 version I and one with a 70-200 2.8 version II.
So here's the question: Why is it that with the 300 the shots through the glass are very blurry, whereas the shots with the 70-200 are crystal clear? I try to get as close to the glass as possible, but for some reason the IQ with the 300 through the glass sucks in comparison with the 70-200. I even tried switching bodies, but it's the same (I have a 1D3 and 1D4). If I'm above the glass, the 300 is stellar. And the 300's focusing locks on, but the end result is horrible.