Lessons Learned.

 The first thing that I realised was that the best size for this work was in fact to use the smallest circular plate. The medium sized one was O.K., but I didn't even use the biggest one as it was just too big at 9cm across.

 Then I learned that double sided sticky tape does not hold a piece of gel onto Perspex, it just falls off. How I can attach the gel to a backing is going to be a series of experiments.

Finally I found that each plate had to have more than one imprint on it for the best effect, as in the middle image here. It was fun trying it all out, but I have a way to go before getting prints that I can use.