Compare FWHM and eccentricity between center and periphery?

[RadOD]

Subframe selector allows comparison of FWHM/eccentricity between images, but is there a way to map their values within an image?   I am adjusting a field flattener spacing and I'm wondering if there is an objective way to do it.

[RickS]

The FWHMEccentricity script can produce maps showing this.

[RadOD]

Thanks!

This is fascinating!  This is sort of what I was expecting:


But this is not! I don't know what to make of it yet...