No idea about that, but a suggestion for an easy fix you could make, and one that I made to my own personal version of ESB that I watch is use dynamic brightness adjustment when luke is underneath the walker (and the shot of the tow cable hitting the bottom) and make it darker under there since no light should really be hitting it, at least not to that extent. Then when Luke ignites his lightsaber boost the contrast so that the core of the saber is white but the rest of the shot is still dark and looks kind of "glowey".