I managed to produce a 2 frame mosaic of my recent STL6303 NGC 371 shot with an old STL11K shot of NGC 346. Although the images were from different cameras and one was a HaRGB with the other being a LRGB, photomerge seemed to do a pretty good job of stitching them together.
This is the link to the NGC 371 page:
http://members.pcug.org.au/~stevec/N...STL6303_RC.htm
This is a direct link to the mosaic:
http://members.pcug.org.au/~stevec/n...photomerge.jpg
Cheers
Steve