Insanity by Consensus.

c86:

Dangerous Days: Making Blade Runner, 2007

Last night I finally watched the definitive documentary on the making of Blade Runner, that along with The Shining is my favourite film of all time. With a runtime of 3 hours 34 minutes, I learnt so much about the rocky creation of the film, on set problems, and everything involved from its inception to completion and beyond. Seeing screen tests and lost scenes for the first time was a treat, as well as the extensive interviews with cast and crew

For me, one of the most interesting parts of the documentary centred on the design and art direction of the film, especially the involvement of Douglas Trumbull and Syd Mead. On a sad and slightly nostalgic note, the film was one of the last to employ special effects that were entirely created in-camera. Footage and explanation of this process were fascinating, including intricate model making, matte paintings and various visual tricks that were composited on film using a process of multiple exposures. The epic opening scene of Hades, the futuristic Los Angeles, involved a forced perspective set and up to 9 multiple passes of film exposure

Douglas Trumbull explains more about these Blade Runner effect sequences on his website:

Hades Landscape
Spinner Vehicles
The Bradbury Building / Blimp