Some more info:
I tested this with the simulator creating a 2x2 mosaic.
The problem also is evident here too. I've also had the same issue in real world use with bigger mosaics like this.

Mosaic tool settings:



Simulating CCD view in Stellarium using the RA/DEC from the mosaic jobs, there is a 30% overlap on horizontal panels when there should be no overlap. Vertical panels are correct.


Read More...