Lucas wanted a row of elevators in the Death Star and McQuarrie made them
indicidual tubes along one of the walls of the many deep canyons in the Death
Star.
There are a variety of robots, mutations, and oddball characters here, as
throughout the film, filling out the concept that the nature of a galactic
civilization was that they adapted in a variety of modes to the various
environments.
The large spaces may have helped air circulation, but McQuarrie also speculates
on the need for psychological space on such a space station.
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(Last updated at: 980414)