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.

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.

If you are suffering a moderate to strong color blindness, it’s always a hassle if you have a crayon box in front of you full of colored pencils. – How about naming them? Could this help?

A french student from a packaging design class had just this idea. All white crayons named with the corresponding color.

Her professor says: “After all isn’t color subjective? Think of the colorblind people for example. So here’s the objective set of color pencils.”

Ok. I am colorblind and think about it. And I think it’s of no use for us colorblind. Why?

As a colorblind person I have great difficulties in seeing, differentiating and specially naming colors. So if I see a certain color I can’t tell you if it is red or green, because I can not see it.

Now, let’s imagine I grab a colored pencil which is just plain white only with its color name printed on it. I actually don’t really know how this color looks like as I don’t know which name corresponds to the color I see. Ok, if I know the color of a certain thing it could help (I learned that leaves are green—most of the time). But otherwise the name is not a clue for me at all.

What I need is to see the color so I can compare it if it really is the one I need. And even if I see it, there is still a big chance that I still will mess them up. So names are for nothing and colors are unfortunately not much better.

Hey, everybody knows that red-green color blindness is the most common type of color vision deficiency. How can I claim that it doesn’t exist at all? – I’ve got not only one but three reasons which support my statement that there is no type of color vision deficiency which really deserves the name red-green color blindness.

When you realize or get told that one of your friends is colorblind, most probably you remember the term red-green color blind and try to imagine, what this means:

• My friend can neither see red nor green?
• He can’t distinguish those two colors at all?
• Besides red and green he has no problems with colors?
• Or maybe red and green look like gray to him?

This is all wrong and the reason why I say, that there is no such form of color deficiency which should be called red-green color blindness. And here are my three arguments which strongly support the sentence: Red-green color blindness doesn’t exist.

(1) Red-green color blindness doesn’t exist, because there are really two distinct forms: red-blindness (protanopia/protanomaly) and green-blindness (deuteranopia/deuteranomaly). Protan defects are caused by a shift of the peak of the red sensitive cones in your eye towards the green peak, or if they are missing at all. For deutan defects the same is true for the green sensitive cones. And even if the naming sounds like a combination of both, you are suffering just under one of them.

(2) Red-green color blindness doesn’t exist, because if you are colorblind you will encounter problems with colors from the whole color spectrum. There is no such color vision deficiency which is only focusing on certain colors like red or green. The so called confusion lines can give you a quite good understanding of how a color spectrum is seen by color blind people.

(3) Red-green color blindness doesn’t exist, because if you are really colorblind, you really can see only in gray. This is called monochromacy or achromatopsia, which affects only a handful of all color blind people. In this case it doesn’t make sense to talk about any colors at all. On the other side, if you have only problems with your red, green or blue sensitive cones, this isn’t actually color blindness but some form of color vision deficiency. Or as I put it in another article: Color Blindness is not ‘Color Blindness’.

If you still think, that you are suffering from red-green color blindness, have a look at Which Type of Red-Green Color Blindness is It? and learn more about the real type of your color vision deficiency.