It’s not a trick, if you’re wondering. There actually is something to see.

  • M137
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    9 months ago

    These never worked for me because my eyes are too broken. I got -13 Astigmatism so with glasses the image is too blurry even a few cm from my nose, and without glasses it’s clear right up on my nose but anything beyond that is a blurry mess.

    • Albbi@lemmy.ca
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      9 months ago

      Actually the distance from your nose doesn’t matter. Think of it this way. When you look at a screen or piece of paper, both of your eyes are trained to converge on the paper or screen. These images have a hidden point somewhere beyond the paper/screen where your eyes can easily focus and see the hidden 3d image.

      Hold your hand 3 inches behind your phone. Move your phone away and focus I your hand. Return the phone while maintaining your focus on your hand.

      That’s all it takes. Different images have different focal points, so 3 inches might work for this image but not for others. Might have to experiment a bit. But if you can see your hand in focus, then you can also see these images.

    • nieceandtows@programming.dev
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      9 months ago

      It’s pretty easy to do once you learn how to. Look for repeating patterns in the image, and start crossing your eye (doesn’t matter distance from the screen). And stop just when two copies merge. You can practice by holding out your two thumbs and slowly cross your eyes until the two thumbs merge in the middle and you see three thumbs. Or draw two dots on a paper and cross your eyes until you turn them into three.