OK this is straight forward question from a guy who tries to understand everything behind blue/green screens etc.
After watching several documentaries, mostly about Star Wars and Star Trek I noticed one thing - ILM created (or popularized?) a new method of filming miniatures - filming them in multiple passes using their motion control camera system.
I know that they did like one pass with the unlit model, one pass with only the lights etc., however I have no clue WHY they did shoot it like this? Does the final optical composite look more “real”, more “3D”? Or is it simply because of some purely technical reason, e.g. minimize the “blue/green spill” problem?