May I suggest a Forum (or sub-forum) dedicated to Paper Negatives?
The subject is not easily researched on APUG.
Searching for "paper negatives" yields far to many posts referring to film negatives.
I recently initiated a post on the subject, and it's catchig quite a bit of interest:
Gandolfi referred to a thread on the LF forum which has lots of good information:
Paper negatives are Pure Analog, and APUG ought to be the first place one should look for information...