I rented a rental photo for a day - the 2x native extender fits perfectly. The pictures are different from what I shot with my very good Sigma 2.8. That is, as he wrote "the nature of the image" - and also demanding of a person. Forget about the focus - it is accurate. I have 60D, so for someone who has a full frame and who is looking for a fix, this is probably the lens in the top three, after 16-35 2.8 and fifty dollars 1.2. But it's up to you! Take and test.
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