Lay the screen on a newspaper-covered surface. Pour emulsion on the screen and spread it in a thin even layer to cover the entire surface with a squeegee.
Flip the screen over and apply emulsion evenly to the other side. Allow it to dry for two hours away from direct light.
Cut a 2-inch hole in the middle of a disposable tin pie plate using a utility knife.
Prepare the light. The bulb should be placed through the hole in the pie plate and into a plain corded socket with no shade. Hold the socket upside down and don't plug it in until the bulb and pie tin are in place. Hang the cord so that the bulb is suspended about 12 inches over the burning surface.
Place a piece of black felt the same size or larger than your screen on the surface. Lay the screen on top, followed by the transparency, then the sheet of glass.
Turn on the lightbulb and allow it to expose the screen for 45 to 90 minutes, depending on the size of your screen. For a 10 inch-by-14-inch screen, 45 minutes is long enough.
Rinse the screen under cool running water to remove the emulsion, leaving you with the image burned on the screen.