Hi Ray,
I haven't been too concerned with the noise levels of the individual panels.
The noise levels with the fewest number of subs are already so low that I have decided to use all subs.The main problem is differences in the sky background between the panels.
So I had to normalize the panels.
The script linear-fit is unfortunately not suitable for this.
So searched the net and then came across the script DNA linear fit.
Using this script I was able to normalize the panels so that all panels have the same median.
Then use mosaic by coordinates.
Works much better than image registration.
However, all panels must have a plate solve. This is not a problem with the script imagesolver.
You can find the dna-lineair fit script here:
DNA Linear Fit | PixInsight Forum
or here:
PixInsight DNA Linear Fit - Chaotic Nebula
Best regards,
Mike