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by blattimwind 2999 days ago
This is longitudinal aberration; visible even in the center, so the test chart isn't actually in focus.
2 comments

No, that's chroma aberration(of which longitudinal is a type), the Canon 100/2 exhibits the exact same purple fringing on high contrast areas. I know because it's what I moved from when I got my 135L.

If that was out of focus you'd see a clean transition from black->grey on the edges and a lot more of the detail would be lost.

It is longitudinal aberration, but that just means that you can't actually get all colors in focus.

It can be nice for portraits but in general is a flaw.