Semi interesting story. Was driving my exwife around the city and noted how the color tint on one of the buildings as cool. It was a checkerboard pattern or something in different shades of blue/green. She couldn’t see it and said it was “glass colored”. She couldn’t really get how the glass was tinted a color.
Anyways printed out a handful of these and yep, she had partial color blindness. That’s how she found out.