Something doesn't sound right here. They should not have .JPG after them. If they are CR2 files, they should open in your Canon software no worries. Also, Deep Sky Stacker will open them when you load them to stack. If you saved them to your card and then transfered them to your PC, you may have corrupted them somehow or tried to save them as .JPG files and it has bunged them up some how. Are these Astro shots? Could you not capture them staright to your hard drive?
