Daran wrote: Jack Flesher wrote: And FWIW I could not detect a single iota of increased noise in any shadow region after the crop. I am not claiming it wasn't there, in fact I am certain it would be if I had a scientific way to measure it. I'm just claiming I could not visibly detect even a hint of noise anywhere even at 400% magnification as a practical point.
You are completely missing the point. There is a nice writeup with example images about how this works over at dpreview: https://www.dpreview.com/articles/2666934640/what-is-equivalence-and-why-should-i-care/
No. We're correcting the impression generated because somebody decided it became necessary to use the technical definition of "exposure" which is different than it's been used by photographers for the past hundred years; amount of light captured on a given unit area vs amount of light falling on the actual subject... It’s real life application of a given aperture used in a given exposure not changing because we cropped. We understand the theory, we don’t agree with how some people try to equate that theory to a zero net difference between f4.5 in a 400mm lens if we crop to a 560mm equivalent FoV, and f6.3 on a 560mm lens. The reality is the f4.5 lens “required camera exposure” remains 1 full stop faster than what is required from an f6.3 lens of any focal length!
Sep 21, 2026 at 10:40 AM
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