What's My JND? 0.0066
Can you beat it?
www.keithcirkel.co.uk/whats-my-jnd/?r=ApkkKP__-_ev
#WhatsMyJND

Interesting little project, I think my monitor was a larger issue here than my eyes.
What's My JND?

Find your Just Noticeable Difference in colour perception. How small a colour difference can you actually see?