wrote about Revealing Watermarks:
Many thanks for the response and info. I get it now. I knew it was possible– a few years ago I began a mini project and I encountered this very issue (a part of a watermark hidden by ink of text). Although slightly different, I knew it was possible to do a separation in antique art, re the paint layers, and I had discussed it also with someone using PXRF (scanning) on pottery — but what you describe is pretty straight forward – I will have to get your book! …update: I just ordered it. Probably I can be more engaged in my queries when I have the book in hand. Looking forward to that,
Stay well, and really glad you have this up and running. I have been very dedicated to the concept of authenticating in codicology, and this will make a difference I feel.