Very nice video Robert.
As far as experiments, I thought of one you might want to try (unless you thought of it already
).
Take 2 containers..Not very deep or big, maybe 1/2" deep and 5-6" in diameter. Inside these containers, put about 10 of those UV beads. Cover one with a piece of your overlay and the other with the piece you purchased.
Then set each of these in a room in your house, right next to each other, where you have other posters hanging. This way, it is the normal, everyday, indirect light your other posters are exposed to, vs direct sun, which even the best UV material wont protect against after time.
Let the beads sit and do their thing, and show how each set looks looks after a day or 2 (or longer if need be). (And have a third container, kept in total darkness, so you can use that set as the control). This would then be another clear way to see if both sets turned the same depth of color, of if one set remained lighter.
Jeff