A LUT is a lookup Table containing information about color, contrast, gamma, etc. Last Christmas, Team Negative 1 released a "Grindhouse" scan of an old 35mm print of Star Wars, The Empire Strikes Back in all of it's pre-Special Edition glory. The print is very dirty, and the colors are a little off (The end credits were green rather than blue!). An Original Trilogy .com Member, NeverarGreat, made some color corrections and saved the results as a LUT file, which you can download from here: http://originaltrilogy.com/topic/Team-Negative1-The-Empire-Strikes-Back-1980-35mm-Theatrical-Version-Release-Details-and-Updates/id/16108/page/47
In this video, we demonstrate how to apply that LUT to the Grindhouse Edition of ESB using Adobe After Effects, and improve the colors.