Star Wars: Rogue One - 10 Major Reveals From The Celebration Europe Panel
A couple of hours before Rogue One, ILM hosted a panel called Star Wars Archaeology that looked at the process of developing the visual look of Star Wars. Needless to say, it was fascinating. Along with talks on the practical effects in The Phantom Menace (there's more models in that film than any other Star Wars movie) and the development of The Force Awakens, there was a presentation by John Knoll on recreating the style of A New Hope for Rogue One.
A big part of the speech was how he painstaking replicated the wire model of the Death Star plans line for line so they could be included in the film. It seems obvious that there'd be present, but it's exciting confirmation all the same. The process wasn't easy though; the original had been lost, so he had to work off a sample from a designer video. The result, however, is amazing (he half-wanted to use it for the trailer).