I am an amateur photographer who shoots high school sports for our local high school. I wanted a fixed aperture lens but found it limited my distance. I bought it hoping to get some of that distance back. There is no sacrifice in quality when using this lens. You really need an f2.8 lens, and you also need to be aware that it adds an aperture, so the best you can do with this teleconverter is f4. Still really worth it in my opinion.
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