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01-13-2019, 05:05 PM   #721
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Having looked into this when Falconeye was still around, he pointed out the best lenses are sharpest at 2.8, and he had a theoretical explanation. Lenses like the 31 are sharpest at ƒ4. Most lenses are sharpest at ƒ5.6. But you can almost predict how sharp a lens is by where it's sharpest. The DFA* 50 1.4 meets his criteria for expecting sharpness well beyond normal. I'd be interesting in knowing if there really is a lens limited only by diffraction somewhere, I've actually never heard of one.


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