Darth Lars said:
The blue tint of the set also reflects the general mood in the movie when Luke enters the throne room. Everything the Rebels are doing at this point is going bad: on Endor, in the space battle and on the Death Star.
Subtle lighting im all for. But the 'in your face' colouring of the SE's destroys the scene almost as much as the general mood on Hoth in the DVD's.