I first learned about stereograms in 2001. Back then, the term was new to me and I had no idea that it was possible to see 3D shapes on a 2D screen with the naked eyes.
What are stereograms you ask?
A diagram or computer-generated image giving a three-dimensional representation of a solid object or surface
Wikipedia, as usual, has a nice article explaining stereograms.
After a long week of trying hard, researching and learning various techniques, I managed to see my first stereogram:
How to see stereograms?
In order to see this stereogram, try to gaze at the picture without focusing on any detail in particular. The goal is to be able to see the two visual aid markers at the bottom of the picture converging, each forming a double, then the doubles merge and form a third marker in between the two original markers. The moment you see three black marker squares instead of two, then the hidden 3D image will reveal itself.
There are two ways to see stereograms:
- Parallel eyes technique – You gaze past the 3D picture and then the 3D image will pop out from the screen.
- Crossed eyes technique – Your line of sight meets earlier than the 3D image and the 3D image will appear engraved deep inside the screen instead of popping out.
Parallel eyes technique
With the parallel eyes techniques, you gaze past the stereogram picture. Relax your eyes and let them wander. Slightly observe the visual aids. You will know that you are gazing properly if you observe the aids moving around and finally a 3rd visual aid shows in the middle.
Crossed eyes technique
With the crossed eyes technique you have more chance to see the stereograms. Grab a pencil or use your finger and use it to cross your eyes while looking at the stereogram. Move the stylus closer or further from your eyes as you cross them and observe if the 3rd visual marker starts to show. When the 3rd marker appears, you will see the stereogram deep down in the screen.
I mastered the crossed eyes faster, but of course, some 3D pictures / stereograms are designed to be shown using the parallel eye technique so they appear as designed.
Time to practice
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