[Klaus]

I've to admit that I'm not totally sure what you are referring to here. Is it about the bluish hairs in the dead center?

If so, I sort of doubt that this is lens-related fringing.

Chromatic aberration can indeed appear in the form of purple/red/blue/cyan/green halos - but that's not close to the center (unless the lens has an issue).

It's probably just related to the reflective characteristics of these hairs.