Sep 13, 2017
I just made a colorblindness test.
To use it, copy/paste the image into a drawing program and take the Hue slider. Drag it around and look for any areas in which you can’t see the border between the colors.
In the image above, I can not see any difference between the 3rd and 4th circles. And when I change the hue sliders to the green or red areas, three circles combine.
Red/green colorblindness is common in men, (so I’m not surprised). Turns out I may be a little less tuned to purple/blue too.
This may also just be a test of how well computers can display colors. The ones that blend together are definitely seen as separate by the computer, but perhaps it doesn’t know how to show it. I can’t think of a way to be sure.