http://www.nikonchat.com/nikkor-80-400mm-review-2/
Sigma 120-400mm OS vs VR Nikkor 80-400mm?
I have read very few comments on these two lenses to reach a final decision. I know that the Nikkor is obviously better, but is it worth the price difference? I do bird watching, but no action or sports photography.
They are both observation lenses decent bird. The relatively Nikon AF show not to be much of a problem since the observation of birds is almost always at or near infinity. You can also check 50 500 or 150 to 500 sigma lens, those are the ones you see more with the bird-watching on a budget.
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