Dan380 i was reading your comment about the sigma lens, i just bought the sigma 135-400mm lens and had it out yesterday, i thought it was a good buy, as the price of the cannon 100-400 was just out of my budget, yeah with my sigma 70-300mm i was the same getting blurry shots but there was some good shots too, the ones i shot yesterday were in not too good weather situations but i thought they turned out not too bad.
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