ProFit now supports free, fixed, and follow fitting for multiple images, meaning it usefully supports multiband (different filter) image. These images can potentially have different PSFs, offsets, position angles and pixel scales, but it does take a bit of thinking on the users side in such complicated scenarios (flexible doesn’t mean simple). Update from the usual place:
Keen users might also want to update their Rfits and Rwcs packages from my GitHub (asgr), since these now support a wider range of WCS (effectively everything in wcslib, including distortion fields etc).
Slightly related, if people are keen to join ProFit related efforts with Euclid, then please get in touch. I’m 100% sure what the institution politics of involving more people might be (I’ll have to check), but assuming various entities are supportive it would be good to get some help since it is a pretty big data processing task. If you already happen to be at a Euclid affiliated institute, then that will no doubt help.