Blog

Are you ready for a little nostalgic trip back to the 90s? Back then, there were these mysterious images that seemed, at first glance, to consist only of wild patterns. But for those who found the right angle, a hidden 3D motif could be discovered. We’re talking about autostereograms – let’s take a closer look together! (Pun intended) 👀

What Are Autostereograms?

Autostereograms are special two-dimensional (2D) images with repeating patterns that contain a hidden three-dimensional (3D) motif beneath the surface. The 2D designs often appear as random patterns or color blobs at first glance. Only when the correct technique is applied can one recognize the hidden 3D images.

The History Behind Autostereograms

The technique of autostereograms is based on the principles of stereoscopy, which originated in the 19th century. In 1838, Sir Charles Wheatstone invented the stereoscope, a device that displayed two slightly different images in such a way that a sense of depth was created when viewed. Stereoscopy was used for spatial representation in cartography and for scientific purposes.

The Beginnings of Autostereograms: Random Dot Stereograms

In the 1970s, the first random dot stereograms emerged, which are considered the direct predecessors of autostereograms. These images consisted of randomly arranged points and created a hidden 3D image that could be viewed without a stereoscope. Those who relaxed their gaze correctly could perceive spatial structures within these random patterns.

Single Image Random Dot Stereograms (SIRDS)

In 1979, Christopher Tyler and Maureen Clarke developed the Single Image Random Dot Stereogram (SIRDS). Unlike classic random dot pairs, SIRDS were designed as a single image and functioned without a stereoscopic device. Through a special calculation of difference stripes next to a reference stripe, a pattern was created that generated a 3D image when viewed with a relaxed gaze.

Single Image Stereograms (SIS)

In the 1980s, the technique evolved further by replacing random dot patterns with actual image content. This method, known as Single Image Stereogram (SIS), showcased hidden 3D motifs within realistic images. This technique was popularized in the early 1990s by the Magic Eye book series, published by Tom Baccei, allowing viewers to discover concealed 3D objects within lifelike image scenes.

Patterned Autostereograms

Also in the 1990s, the development progressed to patterned autostereograms. These autostereograms did not use random patterns but rather artfully repeated designs that hinted at the motif. These patterns revealed the hidden 3D objects and contributed to the popularity and success of the Magic Eye book series, making the genre known worldwide.

Side-by-Side Stereograms

In addition to autostereograms, there are side-by-side stereograms, also known as cross-view stereograms, which use a pair of images to create the depth effect. Viewers must cross their eyes when looking at these images to perceive the spatial effect.

There are many other types, combinations, and variations of stereograms, but those mentioned here are the most well-known. Ultimately, it is not so important for most viewers which technique is used. The main thing is that hidden motifs are waiting to be discovered in these images. Now let’s look at how to apply the optimal technique to bring these 3D images to life.

How to View Autostereograms

Once you’ve figured out the technique that works best for you, recognizing the 3D visualization in any image becomes quite easy, regardless of ambient light or other possible distractions.

1. The Setup: Find a quiet spot without distractions and with sufficient light.

2. Image Positioning: Hold the center of the image directly in front of your nose. It should be blurry.

3. Focusing: Try the Parallel View or the Cross View.

Parallel View: Try to look into the distance as if you are gazing at a point behind the image, as though looking through a glass pane. Relax your eyes and suppress the natural urge to bring the image into focus. This technique, known as Parallel View, helps promote the proper alignment of the image patterns.

Cross View: If you’re unable to recognize the 3D motif with Parallel View, try the Cross View technique. Hold the image as before in front of your nose and cross your eyes slightly so that your eyes overlap the patterns. Some autostereograms are better suited for this method, so experiment with both techniques to see which one helps you the most.

4. Slow Movement: Slowly move the image away from your face. Many find that blinking frequently during this process helps reveal the hidden 3D motif.

5. Appearance of the Motif: If done correctly, the 3D motif should gradually appear. It may take a few seconds for you to see the motif clearly.

6. View the Entire Image: Great! Once you perceive the hidden image and the depth, you can take in the whole 3D picture. The longer you look, the clearer the illusion will become. The farther you hold the image away, the deeper the perception will be.

Still Not Working? If you’ve been trying for a while and still can’t see it, try printing the images on a sheet of paper. Many people find it easier than viewing on a smartphone or computer screen. And if the example image doesn’t work, try another one – some images are easier to recognize than others.

Autostereogram Gallery

Now that you've mastered the technique, try to spot the 3D images in the following autostereograms. I created these using a free online stereogram builder, and the hidden images should be easy to identify. You’ll find the solution revealing each 3D motif below each image in the expandable section. If you’re having trouble seeing the image on screen, just click on it – you’ll be redirected to Google Drive, where you can download and print it for easier viewing.

Creating Your Own Autostereogram

If you want to create your own autostereogram, there are plenty of tools and methods available, and many don't require advanced knowledge. For instance, if you'd like to turn your own logo or a simple shape into an autostereogram, I've found an easy approach.

First, you can use 3D Slash to create a 3D object from your image and modify it as needed. Export the result as an OBJ file, then use ImageToSTL to align it properly and convert it to PNG format. Finally, upload the PNG to EasyStereogramBuilder, add a suitable background, and your custom autostereogram is ready!

This is a simple method, but if you're aiming for a more professional result, you can use advanced 3D software, such as 3D Studio Max or other CAD programs, to design a detailed 3D model. Once your model is constructed, you can export it as an STL file and convert it into a depth map. This approach allows for greater precision and complexity in your autostereogram designs, capturing finer details and adding a more dynamic sense of depth.

Closing Words

I hope you enjoyed this nostalgic trip! And if you weren’t familiar with autostereograms before, I hope this article has sparked a new interest in them.

Pro Tip: If you're looking for a gift or want to treat yourself, I highly recommend the Magic Eye books or the book Hidden Worlds by Thorsten Schmitt! (unpaid promotion)