How to Make a Spinning Optical Illusion

If you spin a rainbow umbrella, it will appear white.

Optical illusions prove that not all things are as they appear. Illusions occur when the brain fills in gaps in received visual information according to expected patterns that do not always match reality. This unreliability of the eye is what makes the seemingly solid images encountered daily in print, movies and on television and computer screens possible. Illusions need not be confined to technology or skilled artists, however. Anyone can trick the eyes by making a moving, spinning illusion in his own home using only basic materials and the colors of the rainbow.

Things You'll Need

• Color printer
• 2 sharpened pencils
• Scissors
• Cardboard
• Glue

Instructions

1. Print out (or make for yourself) a blue and yellow color wheel and a rainbow color wheel.

2. Cut the wheels out.

3. Trace the circumference of the wheels on to the piece of cardboard, using the pencil.

4. Glue the paper wheels onto the cardboard circles. The cardboard will aid the illusions by giving the color wheels stability while they spin.

5. Pierce the wheels through the center with the pencils and move the wheels up to around the eraser area to see the illusion most clearly.

6. Hold one of the pencils between your palms and move your hands in opposing horizontal directions to make the pencils spin between your palms. The rainbow wheel will appear white while spinning and the blue and yellow wheel will appear to contain many other colors such as red and green as it spins.

Tips & Warnings

• The blue and yellow illusion will work with a wheel of any two other contrasting colors, even black and white.

References

• Illusion-Optical: Blue and Yellow Spinning Wheel Optical Illusion
• Big Shot Camera: Spin a Color Wheel and See White

Resources

• Rainbow Wheel
• Black and White Wheel