DEW1.5. Dueling Beams of Light
The computer-based color explorations allow millions of colors to be viewed efficiently, but do you really believe it? Make and mix your own beams of colored light to see what happens.
Materials
- Two overhead projectors, or two slide projectors, or one of each
If using overhead projectors, two sheets of thick paper or cardboard with cut out slightly smaller than filters If using slide projectors, two slide holders for filters - Filters
Pack of color filters (at least 6 colors – red, green, blue, yellow, magenta, and cyan) from a distributor of science education materials. You may also order filters from lighting companies that sell colored gels for theater productions – see source of equipment.
| Color | Rosco Filter |
|---|---|
| Red | Deep Salmon #42 |
| Green | Standard Green #2004 |
| Blue | Light Sky Blue #67 |
| Yellow | CalColor90 Cyan #4390 |
| Magenta | Light Straw #11 |
| Cyan | Calcolor90 Magenta #4760 |
Make your own filters using petri dishes, food color, and food dye.
What To Do
Darken room.
Turn on both projectors, put filters in place to color each beam, and merge beams.
Challenge 1: Find two color filters in which the merged beams of filtered light produce yellow.
Challenge 2: Stack these two colors over one beam of light (turn off second projector) and see what color is produced.
Challenge 3: Find two color filters in which the merged beams of filtered light produce your favorite color.
Challenge 4: Find two color filters that produce your favorite color by stacking the filters over one light beam.
Movies created by Marion Tomusiak,
Museum of Science, Boston: