Optical illusions

[Skeptisk]

I say optical illusion but really an optical effect. Looking through a screen with a hexagonal pattern at the screen behind with the same pattern seems to give a large pattern. I am not sure how this works. Anyone with an idea?

[gmasterfunk]

Moire effect

https://youtu.be/721a_dev93w

[Pitre]

That is weird.

More detail (and much more weirdness) here: https://youtu.be/39pBXE3F88E

[gamefreaks]

Skeptisk said:

I say optical illusion but really an optical effect. Looking through a screen with a hexagonal pattern at the screen behind with the same pattern seems to give a large pattern. I am not sure how this works. Anyone with an idea?