Now that was an excellent read, quite astounding.

Please post to HN front page and re-post as updates occur!

BBC archivists also figured out how to recover colour information from black-and-white film.

https://www.youtube.com/watch?v=CjK-b4x9ZmQ

This is a great read about the restoration of a lost archive, but it is worth noting that in this case the source material was similar to what is being converted and destroyed now: analogue video tape recordings from a low-resolution source material. The source was recorded in PAL/NTSC/SECAM and the conversion process can be completely lossless and still end up with a copy that has every bit of information that was on the original.

In the case of the Morecambe and Wise recordings, this was video to film (with an additional step to try to lose information in the first conversion so that the scan lines were less visible) so the interesting technique here was simply in restoring a degraded source. Unlike scans of film negatives, there is no way a new process or technique is going to dig out information that the original low-fidelity recording system was simply unable to capture.

It's not uncommon to see vital documentary footage that was crudely digitized twenty or more years ago, to a resolution that was less than standard TV resolution at the time. It looked okay on TV then, but looks horrible now, and the originals are lost forever (since that was the point of digitization, to save rent money in the long run.)