Again, Lowry didn't change the colors (I refuse to use the word "correct") - why do so many people think they had something to do with it ? - and they didn't scan it. They received the 1997 SE "negatives" scanned as a series of 1080p pictures.
Maybe this would be helpful ? http://web.archive.org/web/20140528152100/http://secrethistoryofstarwars.com/savingstarwars.html