Thanks for all the info. I am using only a bulb blower, but I wonder what 3M transparent tape you are using. I only know the sticky tape that uses some glue, but I don’t think that’s what you are talking about. Is it something electrostatic?
If you have the opportunity to test with infrared light source, I would really be interested in the results, since used with a scanner this technology is a miracle. It would really be great if it could be adapted to a camera “scanning” workflow as well. But I did not find information on how much the defocusing due to different spectrum is a practical issue or a myth, and if such a technique would lead to some reasonable results. But since I have no test setup, I did not have an opportunity for tests yet.