Hand-Painting Glass Gobos

by Michael Eddy
For Buglisi Dance Theatre’s Moss, Taylor wanted to create an environment that was varied and natural and had that idea of a forest. He found his hand-painted slides to be perfect solution for his design intention.
For Buglisi Dance Theatre’s Moss, Taylor wanted to create an environment that was varied and natural and had that idea of a forest. He found his hand-painted slides to be perfect solution for his design intention.

Lighting Designer Clifton Taylor has been producing his own hand-painted glass gobos now for over 20 years. In fact, it was the introduction of the ETC Source Four ellipsoidal, with its dichroic glass reflector that pulls a large amount of the heat energy out the back of the unit, when he first put paintbrush to glass gobo. “It certainly wasn’t possible before Source Fours were ubiquitous,” notes the LD. Recently, Taylor created nine glass gobos to use in his backlight system for the dance piece Moss produced by Buglisi Dance Theatre. He recently walked SD through his process. 

I have the glass blanks cut to the same size as the gobo holder itself so the glass slide can go right into the gobo slot without a holder and have enough glass on the outside of the unit to pull it out. I go to a local glass distributor, GrayGlass in New York—but any good glass provider would work— for quarter of an inch thick, cold-rolled, clear Pyrex. They also finish the edges for me. The cold-rolled part is important because that process puts little, tiny ridges that are not visible in the glass that allow the paint to bind to the glass. I tried the hot-rolled first, which is smooth like window glass, but the paint would slide off. I usually order the glass blanks about 100 at a time so I always have some in my studio in case inspiration strikes. 

With glass slides, the nice thing is that you can paint on both sides. My process is that I figure out what the mask is first and paint that in black on one side. In the case of Moss, I painted the entire surface black and then scratched away the parts that I wanted light to come through. That’s the other great thing about glass; you can take a razor blade to it and scrape things away. If you make a mistake, you can just scrape it off and do it again. 
Taylor first paints the black mask and then scrapes off where the color will be painted.

Once the mask layer is all dried, I do my color work on the other side. I use Reprolux paint from A. Haussmann Theaterbedarf GmbH in Germany that’s made for glass and high heat projections. [www.ahaussmann.com/en/] It comes in about 20 different colors, in very small vials, and it does tend to be expensive, but it lasts forever. Some of my vials of paint are quite old! Reprolux works a little like watercolor paint in that you can blur or blend it; you can work it while its wet. You can also put down a clear coat and that can act as a medium in a way and then add color to it. The colors are quite rich, but you can dilute them if you want paler colors, but you can also mix it, which I’ve done. It’s the same rules as watercolor in that it’s subtractive mixing. You do have to work quickly though and you should of course do all this painting with very good ventilation.
The color is painted on the opposite side of the slide than the mask.

When the color paint is all dry, I will turn back over to the black, mask side, and go over the black parts with a silver marker. I want to make most of the places that are black silver so that they reflect heat and light. I always make sure that the silver side goes towards the lamp when putting them into the units. 

When the gobo is done, I carefully clean them of fingerprint oil and dust to keep the glass as cool as possible at all times. I then wrap them in paper and label which unit they are for and mark which side goes towards the lens. I also ask that the crew wear gloves when handling them because just like you don’t want to touch a lamp; the same rules apply—you want to keep the slides clean.

When the slides are put in during load-in, I have them sit for 15-minutes at 50%. I do that, not to bake the paint, but to see if the glass is going to crack. Especially if the colors are very dark blues, greens, and purples. They can crack; even Pyrex will crack. They will burn out in a tungsten Source Force over time, but I’ve found with the silvering reflecting some of the heat away, or if the mask isn’t the full frame, they tend to last a lot longer.

I'm really looking forward to trying this process with an LED ellipsoidal, like the ETC Source Four LED Series 2 Lustrs, since the heat concern will be greatly reduced. I think there’s going to be a renaissance with this idea because of the LED source, like in the Lustrs, I’ll be able to do much darker and deeper colors. I’m very excited about the possibilities as a designer.