Definitely agree on the optics of the 80-400. Not equal to the 600/f4 but definitely at least as good as most of the alternatives, and the ones that are better aren't that much better until one gets into the megabuck range. I'm a little surprised at your 300/f4 + TC-14eII results, but otherwise this is about what I'd expect. I don't think the TC-20eIII matches up too well with the 70-200's, at least not compared to how it matches with the big expensive primes.
_____ Brian... a bicoastal Nikonian and Team Member
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