How refined is your color perception?


This unscientific but fun timed eye test asks viewers to guess which square is a slightly different shade than the others. Prepare for a minute or so of eye-melting challenge!

You have 15 seconds on each of the 30 levels, after which you are graded on a scale from blind as a bat to sharp-eyed hawk. After that, maybe you're ready to try a more advanced option.

(via Popular Photography)