Thanks REJSHARP,
I suspect this will only every be a “toy” application, however it’s useful in building my experience for more serious matters. Thanks for your reply and your points are excellent. I intend to get some flat sheet PTFE and use it to make a jig to introduce repeatability. I have a background that includes quality management so Gauge Reliability and repeatability (gauge R&R) is something I understand. I thought I would share the scans to date just for giggles. Two show a useful spectrum. One is the rear of the note which is mostly white so it’s a measure of the paper. The queen’s head is mostly purple ink with an embedded watermark. Both of these would seem a reasonable basis for a model. The third spectrum is over the holograms-hehehe. Not exactly repeatable….
Have you been up to anything interesting with yours?