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Hello,
It is a very interesting site, and I appreciate these "little"informations such as DOF, and so on. My question is this: it is roughly equivalent to expose at, say, f4 and 1/500 or f8 and 1/125. Now some people say that with a slow speed, the light wraps around the subject better than with a faster speed. Given that light travels around 300'000 km per second, do you really think the statement is correct or am I missing some effect ?