DarkFather said:Why the choice to make the chamber so dark?
A number of reasons really.
The original set was blanket lit which highlights that it's largely made up of bits of other older sets and makes even a large space look smaller.
I'm also thinking that any alterations will need a bit of shadow to hide the join and if you are to have a nice open roof bleaching the set in light will detract from that.
My main reason was the element from The Black Hole was dark and I wanted to illustrate an idea without access to 3D modeling skills and it wouldn't work as an illustration if the bottom half was bright white and the top was dark and slightly red.
It's just a mock-up people with better skills and equipment may be able to take the general idea and match it closer to the orignal lighting scheme but I never bought into the Rebels all having white ship interiors and the Imperials all having dark set up.
The control centre in ANH was dark and it added movement and drama to those scenes by having the lights and displays in motion, the white briefing room in ROTJ just looks like a boring set filled with bits and bobs from elsewhere (more Star Trek TNG than Star Wars).