Courses: P4, P14
White light is reflected off a soap film and projected onto the wall. As the film thins the colors change and the bands get wider, until the film bursts.
Setup:
Ideally make the soap solution an appropriate density so that it bursts (dramatically) after one or two minutes -- about the same density as what one would use for washing dishes. Dawn dish detergent is ideal, and it should be mixed with glycerin and water (try 1 Dawn : 1 glycerin : 12 water). The solution needs to be room temperature before the lid goes on or it will fog up the glass walls of the container (but it is easiest to mix up if the water is warm)! Fill high enough that the wire loop can be completely submerged, but low enough that when raised it will be completely out of the solution.
Use the Polaroid projector, and the large spyglass to focus the pattern onto a white surface. Shield as much of the stray light as possible so as not to blind the audience.
