Resource needed: a typical smartphone with a camera
Class Time: 20 minutes
When you look at things in the real world, you have more depth perception and can tell which things are closer and which things are farther away. Taking pictures with a camera changes the real-world experience from three-dimensional to two-dimensional and can result in some humorous juxtapositions.
Students can quickly create an illusion by doing this:
Get out your smartphones
Get into small groups
Find any smallish objects (6 inches or so), such as a soda can, a key chain or a textbook.
Find a flat stretch of floor.
One person lies down on the ground. This person on the ground holds their phone and is ready to take a picture. First, they put a small item on the ground in front of the phone (about 2 feet away).
Then, the student (or students) standing in front of the student lying down with the smartphone move backward on the sidewalk or floor until they are smaller, in relative size, than the object in front of the camera.
Take a photo.
The pictures that result from this activity are fun. They will create an interesting example of relative size and how easily the eye can be tricked.