Crop Factor, Low Light and Aperture with m4/3 lenses? Part 2

Started 6 months ago | Discussions thread
Just another Canon shooter
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Re: Crop Factor, Low Light and Aperture with m4/3 lenses? Part 2
In reply to Anders W, 6 months ago

Anders W wrote:

What I originally said in my first reply to noirdesir is the following:

"What is known based on the laws of optics is that if we take a lens design for a certain format, say a 50/1.8 for FF, and scale it down in all relevant dimensions so as to make 25/1.8 for MFT, the two lenses will deliver the same resolution if we measure per image diagonal (and the MFT lens twice as much as the FF lens if we measure per mm) at the same f-stop as long as resolution is limited by lens aberrations only."

This is trivially true because it is a statement about a non-existing situation. Similarly to the statement: "All 100-leg cows can fly".

As to diffraction, the larger format has an advantage when comparing at the same (rather than equivalent) f-stops. At equivalent f-stops, there is no difference at all, and the impact of diffraction is generally trifling at wide apertures.

At equivalent stops, the smaller format lens can NOT be a scaled down version version of the larger one. This is the relevant question, actually.

Here is a 100% crop of a shot I took yesterday, 135/2 on the 5D2. The guy was not staying still, of course. Default sharpening in LR.

And here is his pin, I did not even remove the CA:

Which of your f/1 lenses can do this?

 Just another Canon shooter's gear list:Just another Canon shooter's gear list
Canon EOS 5D Mark II Canon EF 15mm f/2.8 Fisheye Canon EF 35mm f/1.4L USM Canon EF 50mm f/1.2L USM Canon EF 135mm f/2.0L USM +4 more
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