Essentially, one element of black magic was this...

http://www.photoacute.com/studio/

http://www.photoacute.com/studio/examples/mac_hdd/index.html

But obviously on a far larger scale i.e dealing with tens of thousands of frames.

Black magic took five or six transfers of the same frame and software was used to pick and choose the best elements of each frame and recompose them to create the best possible frame.

This is but one element, de-noising, image and detail preservation are still very much emerging technologies and I'm quite adept at restoration work.

I could even throw in the non-SE'd blu-ray frames just to give alittle more purchase to the frames available to work from.