As someone who has been identifying some modern stamps, I have started a project to obtain images of look alike stamps as an identifier. These would likely be posted to the PNC3 web site since they have similar like posts.
I plan to have high quality images in visible light (close ups for year dates, micro printing. color varieties), long wave, and short wave. I have been acquiring blocks (especially plate since I can correlate to Durland) since tagging is often clearer when you see more than one stamp. I may even try capturing gum differences.
An
ebay seller TBR stamps has done something similar for some stamps.

I am looking for advice on what to capture since I would not like to go back and redo a lot.
Thanks, Al