Color Blind: Which Are Your Blind Colors?

Here is an interesting definition of blind colors: “Colors that are not or not completely recognized by a gray-level scanner.” When I look at my personal color blindness this fits quite well. Compared to people with normal vision I sometimes really think that my eyes are some type of advanced gray-level scanners—but not more.

What I am looking for are the colors we colorblind people have problems to see or distinguish.

color confusion protan deutan tritan
red/orange/yellow/green X X
brown/green X X
Threshold green to white X X
Threshold red to white X X
blue-green/grey/red-purple X
green/grey/blue-purple X
red/black X
green/black X
violet/yellow-green X
red/red-purple X
dark blue/black X
yellow/white X

This first list of colors which are confused by color deficient people is taken from the book Diagnosis of Defective Colour Vision by Jennifer Birch. It is important to know, that these colors are only mixed if there exists no luminance contrast.

From my perspective as a strongly red-blind (protanopia) guy I would say the above list is a quite good image of my color perception. They do also fit with the colors along the so called confusion lines of the corresponding type of color blindness.

I would like to add my personal list of color blind colors which I often can not distinguish. And I also would like to add some examples to them, so somebody with normal vision might be able to imagine a little bit how it feels to be colorblind.

Protan Confusion Colors

dark red/black: If I get an email with words highlighted in red, I can’t see them.
grass green/orange: I couldn’t spot an orange laying in my lawn.
leaf green/red: No red blossoms in trees and no red apples in trees.
bright green/yellow: I can’t see if a banana is ripe or not.
indian summer colors: It’s colorful, but I have no chance to name the colors.
dark blue/violet: I’ll never know what the difference is.
cyan/gray: All shades of blue-green look truly colorless to me.
brown/green/red: Please, don’t talk about red animals in the forest.

I suppose there are many more shades and colors I can’t really see. But this is a list of colors which I often come across and have big problems to identify and classify.

So what are your colors of confusion, problem colors, color blind colors? It would be very interesting to hear also from you which colors cause you the biggest problems.