Zoetrope Kit

Have you ever wondered how your favorite cartoons are made? Each cartoon is actually thousands of individual pictures turned into a moving story. The process of making cartoons relates to three different scientific concepts called Persistence of Vision, Phi Phenomenon and Stroboscopic Effect. These concepts work together to trick your eyes into thinking those individual pictures are continuous! In this project we will work to make a series of drawings look like a movie!

Persistence of vision refers to the length of time the retina retains an image. The retina is the “screen” at the back of our eyes which is sensitive to light. If we see a light flash every tenth of a second or less, we perceive it as continuous.

Phi phenomenon is a result of our brains trying to make meaning from what we see. When we see different images close together our brains quickly try to figure out how they relate to each other. The phi phenomenon is an optical illusion that tricks our  eyes into seeing continuous motion between separate images that are moving faster than 1/10th of a second.

Stroboscopic effect is a visual phenomenon that occurs when a moving image is disrupted by flashing light.

The slits in the black paper create a stroboscopic effect by inserting flashes of light between the images you’ve drawn. This, combined with our spinning pan, creates the optical illusion of a continuous moving image by cycling through those still images at a rate faster than 1/10th of a second. This is persistence of vision and the phi phenomenon at work.

We’ve  got lots more cool and fun experiments that show all of these concepts in action. For example, flip books, thaumatropes and other experiments. Check out our Rosie Riveters website to find them!