Thanks to all who replied on the Historical Puzzle question, I'm going to keep trying to refine location and time and perhaps establish a local horizon for the time of the sighting, then we'll run it all again. If anyone would like the entire text of Willis' escape, let me know off-list and I'll have it all ready in the next couple of weeks. It's for the WWI air-war list I run. Patrick, you don't need images shot simultaneously, just let some time pass between exposures. The earth's orbital motion as well as lunar orbital motion ensures that your second exposure is from a location thousands of miles from the first. I've done this for a couple of lunar eclipses, but with the moon it's hard to get a lot of stars recorded without over-exposing the lunar surface into just a bright blob. I echo Joe's comments on Hale-Bopp. Many of my shots display a startling 3D effect. And BTW, they are indistinguishable from simultaneous shots taken at different geographical locations. Reverse them left-for-right and it looks like the stars are in front of the comet! You don't need Photoshop. Any imaging program that allows precise re-sizing of images will work just fine. You can rotate them to register by cutting one out with scissors if your program won't let you rotate one digitally. __________________________________ Do you Yahoo!? Read only the mail you want - Yahoo! Mail SpamGuard. http://promotions.yahoo.com/new_mail