a demo of lightness illusion

nope. fake

It's not an illusion if the hex values change. Hint: They changed.

this does happen with colors in different lighting scenarios, true, but why lie like this? the square shouldn't change lightness if you want it to be an illusion.

fake

it's two different colors on the left vs right

Reminds me of MC Escher.

That's how automatic exposure on a camera works. Not an illusion.

fake

#9c9197 > #786e6f hmmmm