A simple test to see how diffraction limits the resolution of an image. Two identical images, shot on a tripod with the Sony NEX 5N and the 18-55 zooms lens. One is taken at f8 and the other at f32. There was no reason to tag the images since it’s immediately obvious which one suffers from diffraction.
For this particular combo, i try to stay at least at f8 or maximum f11, since at f16 and beyond, image quality really suffers (and by the way, I should clear my sensor soon, at f32 the spots are really annoying !!)
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