Well, I finally got it fixed. The alignment of the 20 frames was indeed performed using Nebulosity3. What I learned is: 1 + 2 + 3 + 4 = Finished But.... 1 + 4 + 3 + 2 does not always come out that way. What I am saying is.... It is NOT just what you do, but more importantly, the order in which you do it.... Whew! I have GOT to make some notes on this for future reference ! If you would like to see Comet ISON with a "stable" background... http://www.az-douglass.net/astronomy/DMD-ISON.htm David M. Douglass dmdouglass@xxxxxxxxxxxxxxx (secondary) david@xxxxxxxxxxxxxxx (main) Cell (602) 908-9092 -- See message header for info on list archives or unsubscribing, and please send personal replies to the author, not the list.