What's crossview? It's how to see actual 3D depth in an image. It's how to see the colour blellow (blue+yellow at the same time), it's how to send secret messages, and it's how to get really good at spot the difference.

How do I crossview?

Look at this image below, or open the imgur link. Look at the centre line and cross your eyes until you see three images. Focus on the central image and, with a little patience, the image will come into focus with actual 3D effects. You'll know when it starts working. Try to let it come naturally, your eyes know what to do. Also it helps to not have your mouse cursor on the images.

Link to image: https://imgur.com/jTfv2ns

If you've successfully managed to crossview the above image. Try these ones!

A lovely street with light effects

Link to image: https://i.imgur.com/7l4BF5N.jpg

A blellow rotating gem:

Link to image: https://gfycat.com/unfortunatesimplebullmastiff

Spot the difference! Areas that are fuzzy are not the same in both images.

Link to image: https://i.redd.it/sza9l0c2e9k11.png

Find the secret message!

Link to image: https://i.redd.it/jyhbyiuiz5m21.jpg

If you consider yourself a crossview pro, try this tough one below! There's something hidden in there...

Link to image: https://i.redd.it/6lifxw458tc21.png

Cutaway Steam Engine from Vienna’s Science Museum. 

This was a fully functional steam engine for about 40 years before being cut in half for demonstration purposes.