Here's an interesting article on how micro 4/3rds lenses compare with full frame equivalents. In particular, it focuses on the comparison of depth of field, and argues that focal length is invariant (which I agree with) and that it's field of view which changes depending on the crop factor. There's also some discussion on aperture equivalence.
http://admiringlight.com/blog/full-frame-equivalence-and-why-it-doesnt-matter/
I think it is not comparison. But another attempt to talk with mentally challenged (aka idiots) about same things that are most important for internet hamsters. I mean aperture, "true" focal length, etc.
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