What are stereograms?
A stereogram is an optical illusion of stereoscopic depth created from a flat, two-dimensional image or images. At first sight a stereogram looks like an abstract image made of repeatable patterns. But if you look at it in a special way, the hidden 3D picture will magically appear. What you will see is a relief object or objects wrapped with the pattern you can see in the 2D picture. Some stereograms don't have hidden images and consist of several objects placed in rows. When you perceive them, the objects will appear three dimensional, sometimes resting on different levels of depth. Not all stereograms are the same. There are different types and styles of stereograms.
A stereogram is a two-dimensional, computer-generated, graphic image that has a 3-D image hidden in it. This hidden image can only be seen when viewed from the proper perspective. A stereogram has two levels of reality. There is the surface level which often appears chaotic and disorganized with its variety of colors and patterns. There is also the deeper and hidden level of reality, the hidden image, that contains the real meaning of the stereogram. The hidden image is the "real" reality of the stereogram. Because stereo photo exist on these two levels, they can be used to teach lessons about the hidden dimensions of the everyday world in which we live. See if you can find the hidden images.
How to see the magic?
Hold the center of the printed image right up to your nose. It should be blurry. Focus as though you are looking through the image into the distance. Very slowly move the image away from your face until the two squares above the image turn into three squares. If you see four squares, move the image farther away from your face until you see three squares. If you see one or two squares, start over! In order to view the 3-D images, simply stare at the picture until the image starts to take shape.
When you clearly see three squares, hold the page still, and the hidden image will magically appear. Once you perceive the hidden image and depth, you can look around the entire 3D image. The longer you look, the clearer the illusion becomes. The farther away you hold the page, the deeper it becomes. Good Luck!