[here's a very abbreviated version of the story]
At the time computer animation wasn't part of ILM proper. They we're an advanced unit working on future projects. (to put things in perspective, they had just created the concept and initial implementation of alpha channels) So ILM had the contract to do the FX for ST2, and at first the computer division was not expected to help out. But they we're asked to help envision the computer interface design, and after reviewing what shots still needed to be done, decided that they would like to give the Genisis Effect a try. (The animation is 1,621 frames - 67 1/2 seconds) They had hired a guy (Loren) recently who had done fractal landscapes and camera work. (the computer allowed for a more dynamic fly through, not as easy to accomplish with models) Another member of the team (Reeves) invented particle animation, which became another important compositional element in the Genesis Effect. Motion Blur was also refined as a process and implemented in the FXs. All this work was being done on VAX computers. Also keep in mind there was no way to output the final animation, since laser printers didn't exist. Instead they filmed each frame (off a monitor) with a 35mm camera. Frames to render, took between 5 minutes to 5 hours. The mountains took a month of full-time rendering. (i think work on the sequence started in late 81 and was finished in April 82)
Most likely if it wasn't for the Genesis Effect proof of concept the computer generated shot in RotJ (Death Star/Endor) would have been done in a different way.
there's tons more in the chapter but that's the basics, great book, worth getting. Don't believe me read the reviews by Ben Burtt and Alvy Ray Smith (Co-Founder of Pixar) amazon.com Droidmaker page
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