As promised, here’s a little insight into my wet matting technique. Propylene glycol allows the glasspaint to remain wet (“open”) for much longer than a traditional mix, so I can create graduated shadows while the paint is still wet. I can also leave some areas of the glass completely clear to maintain the sparkle. Watch me apply and manipulate a wet matter in real time in this two minute video Glass Painting at the Easel Part 1 and brush back the dry matte to remove highlights in Glasspainting at the Easel Part 2 (2.5 mins).
I am painting glass that has been previously painted, fired and fixed onto clear glass easel plates with a mixture of beeswax and rosin (how this is done). Working at the easel with my painted glass up against natural light (not on a light table) allows me to manipulate the transparency/opacity of each piece, add final shadows, and see the window as a whole.