Yeah, that didn’t work…

Eighty four images representing four and a half hours of exposure on the target. In this case NGC2244, the Rosette Nebula. It takes a few minutes to setup the software to align all of the images, then it takes about half an hour for the software to digest everything and produce a result. At the end of this you get to see if the effort worked. Sometimes it does not.

Complicating the issue is that a number of the sub-frames are taken at different exposures. Finding the correct stars in the these different exposures gives the software fits.

Misaligned Rosette
The result when the alignment routines fail to align all 84 images of the Rosette Nebula.