[dylan604]

One type of archival process that avoids petabytes of data is to scan the original film, process it however deemed appropriate, and then record the finished digital files back to film negative. They will even go to the lengths of separating the digital files into their RGB channels, and then record each channel to B&W film negative. This allows for much greater information to be preserved per channel. It also makes restoring this archive interesting. All 3 negatives must be scanned, and then aligned in post.

I used to work for a company that had a 16-bit film recorder that did this. The recorder was very finicky to environmental conditions especially related to humidity.