Category Archives: People

Probability of Color Blindness

It is well known, that approximately every twelfth man and every 200st woman suffers from some form of color blindness. But what about some real life probability numbers concerning color vision deficiency?

What’s the Chance of Color Blindness?

alphaIf you are a teacher you might ask yourself:
What is the probability that one of my pupils is colorblind?

betaAnd what about the chance to have a color vision deficient pupil
if you have only boys in your class?

gammaYour son is maybe colorblind and joining the kindergarten pretty soon.
How big is the chance, that there is another colorblind child in his class?

delta…and he might also play in a soccer team.
Will he be the only colorblind boy in the team?

epsilonAre you a football coach? What is the probability that
one of your players from a team of 33 has a color vision deficiency?

zetaOr you are leading at work a team of eight persons.
What’s the chance, that you have a colorblind person in your team?

etaLet’s say you know 100 persons. The probability that one of them
is colorblind has to be pretty high. But how high is it really?

thetaIn general, if two people meet, how big is the chance
that they are both suffering from color vision deficiency?

Before I will reveal the answers to the questions above or before you can compute it yourself, you need some more input. To calculate probabilities certain assumptions—like a base probability of color blindness or a class size—have to be taken. The results below are therefore based on the following numbers:

  1. Probability of color blindness in men: 8%
  2. Probability of color blindness in women: 0.5%
  3. Average class size: 20 pupils
  4. Group line-up: 50% male – 50% female

Based on this assumptions I calculated the following probabilities of color vision deficiency. Hover over the letters to see the results. But before viewing them, why don’t you try to answer the questions yourself? Just take a guess and have a look how close you can get to the real probabilities of color blindness.

58%    81%    54%    57%    94%    29%    98.7%    0.18%

And in other words:

  • Almost every teacher or trainer has a colorblind pupil or team member.
  • If you are colorblind pupil, there is a big chance that there is another colorblind child in your class.
  • You can almost be sure that you have at least one colorblind friend.
  • Approximately every 500st handshake is between two colorblind persons.

If you have any further questions, don’t hesitate to contact me or just write a comment on this article.

Colorblind People Feel Handicapped

I was trying to find out, if color blindness does handicap you in your everyday life or if you get along without this feeling. Thank you very much for participating in this poll which was started ten days ago with the question: Do You Feel Handicapped by Your Color Blindness?

Answer Votes
Yes, sometimes 35
No, not really 17
Not colorblind 9

We had just over 60 people sharing their feelings about their color blindness with us. Nine of them aren’t colorblind themselves but still voted. This tells me that there are also a lot of people looking for information about color vision deficiency without suffering from it themselves. Thank you.

The other 52 votes can almost be split into two third/one third. Twice as many people feel handicapped as rather not. Of course this are very subjective impressions but that’s exactly what it is meant to be. Only if you are colorblind yourself you can judge about how it feels to carry this deficiency around with you every single day. And no academical study can ever prove it differently.

Colorblind Poll Results
Colorblind Poll Results

Looking at the numbers it is a very clear result we got here. To tell you the truth, when I started the poll I thought it would be maybe half/half between felling handicapped and not. But this results teach me that I was wrong.

There is also something else we have to take into account. Not everybody suffers the same severity of color blindness. And I suppose people with a less severe form would more likely vote for not feeling handicapped than people with some severe forms like dichromatism (red-, green- or blue-blind persons).

All together this tells you, that colorblind people definitely feel handicapped in their everyday life. There are so many situations and stories to tell where color blindness is a little or even a big burden.

And even so there is no organization or foundation, no real entry point for people looking for information about color blindness; and even more important, nobody represents the concerns of colorblind people towards the government, schools, employers…

Poll: Do You Feel Handicapped by Your Color Blindness?

This poll is finished. You can see the results at Colorblind People Feel Handicapped.

As we know, color blindness is very common among men. Approximately every twelfth men is suffering from some type of color vision deficiency, most often some form of red-green color blindness.

And this group of colorblind people—including the colorblind women among us—can be split into two parts: On one side you have the persons who don’t think that their color blindness is an obstacle for them. They don’t really feel handicapped through it and often forget about it in everyday life.

On the other side we have colorblind men and women who feel in some way uncomfortable with their color vision deficiency. Now and then there are situations coming up where their color blindness handicaps them. It’s not all the time but they think more of their deficiency as a burden they have to carry.

To which side are you belonging to?

Please join in the poll and share your answer. You can also find the poll on the sidebar where you also can get a glance at the results of the ongoing poll on a daily base.

The poll will be running for ten days. So I’ll post and comment the results September 27th on Colblindor.

It would also be very interesting to know in which way you feel handicapped or if not, why not? Please add your thoughts in the comments section and share it with other colorblind visitors.

Interview with Chris Rogers from COLOURlovers

Chris Rogers—also known as the lover named ruecian—is the man behind the site blog of COLOURlovers. I already reported about them, when they covered the topic of red-blindness just a bit more than one month ago.

Out of this first contact evolved the idea of an interview-exchange between the color blindness lovers from Colblindor and COLOURlovers.

As Chris is an expert on the topic of colors, in exchange he asked me some more details about color blindness, including positive and negative aspects of it. I hope you enjoy the following answers from Chris and make sure that you also visit the counterpart of this interview-exchange.

Colblindor: What is your favorite color and why?

Chris: I surround myself with blue because it’s such a daydreaming, imaginative nature. As someone who experiences synaesthesia, a sort of crossing of senses, blue is also the colour that has the best texture to me. With colours, I experience textures along with the visual aspect, and with music, I experience colours and textures. I like a lot of yellow, brown, and blue songs, so, I’ll say that those are my favourite colours.

Colblindor: COLOURlovers is a big resource concerning different aspects of colors. What are the main purposes of your website?

Chris: What I’ve come to find about COLOURlovers is that it’s sort of a playground for creativity, as the site has attracted colour-passionate and colour-oriented professions from fields of design and art. We also have people whom have said they would have never dreamed of playing with colour before stumbling about COLOURlovers, and have since become ‘colour addicts.’ I’d say we’re here to give an open, supportive space to the minds that want to come out and play, and I try to do that with my blog posts by posting something of interest, whether it be science or something inspirational.

Colblindor: Do you think color blindness might be some sort of handicap to join your community of lovers?

Chris: Oh, I don’t think so. Some of the palettes that users (colour-deficient or not) create might look a bit off, and the palettes that are based off of emotions might not convey the same message, but it all ends up meaning something to someone, as I feel colour and colour symbolism is loosely based in interpretation. Just as everyone feels differently about Picasso, everyone can find their own enjoyment in seeing a red palette, even if they don’t know it’s red.

Colblindor: You’re writing all about colors. When did it first come to your mind, that there is also a community of colorblind people and do you offer also some information, help or support for them?

Chris: I made a colour maybe what I guess to be about a year ago called ‘of Colourblindness,’ which was grey. And I remember having a note passed to me asking about colourblindness, and it was really my first venture in trying to explain it to someone. I had always understood the concept, but never had to put it into words. The idea had been in my mind since about that time, and surfaced soon after the blog began as the article that you found, which I wrote on Protanopia.

Colblindor: Do your users ever bring up the topic of color vision deficiency or is it almost not existing among lovers?

Chris: It has been asked before. There was a post on the forum about it, someone mentioned that they suffered from colour-deficiency, and needed some help pulling colours accurately from a painting. I do know that there are at least a few colour-deficient users on the site. It’s not a typical topic, though. I think hearing ‘COLOURlovers’ can be a subject of much fear for someone who can’t see colours like others can, but it’s really not about who does colour better, it’s about a love of colour, and I don’t think colour-deficient or colour-blind people are exempt from that.

Colblindor: Can you tell us something about the ‘headline’ of COLOURlovers “Fight for love in the colour revolution”?

Chris: As far as fighting for love, there is a rating system in place that ranks colours and palettes by how many votes they received and how many users have added them to their favourites lists. I think it’s also about how many comments are left, but I’m not sure about that one. I believe that COLOURlovers is changing minds about colour by bringing it to a field where anyone with hand-eye coordination can play, rather than having it restricted to artists with paint, or tailors with cloth. When I first stumbled upon the site in 2005, I was really cautious about my colour choices, and I created a lot of colours that were already in my life. The community is so very supportive. I’ve yet to see something negative said about something. In fact, I’ve even seen, “I love how ugly this is,” and it gets voted high. In getting used to COLOURlovers, I’ve essentially discovered a whole new world and my thought process as a synaesthete has been allowed externalisation. That’s what I think is meant by the ‘colour revolution.’

COLOURloversIf you enjoyed Chris answers, be sure to also check out his questions, published at the site blog of COLOURlovers. And if you enjoyed my questions, you might like to subscribe to the RSS feed of Colblindor, which ensures that you get frequently the latest updates and insights on color blindness.

Are Colorblind People Disabled?

If you are colorblind, do you feel disabled? And what does the law say about it? Do others have to take some precautions, in a way that colorblind people are not excluded because of their handicap?

There is an interesting discussion going on at, if color blindness has to be looked at as a disability or not. In this case looking at the UK law and their Disability Discrimination Act (DDA). The question is not easy to answer, because there are many different types of color blindness and the law doesn’t really name any disability, but just describes them.

You might like to join the discussion at Are colorblind people disabled?

Do you think color blindness is a disability or not?

Color, What? What Color?

I just found a nice little video at YouTube about Michael, a colorblind boy. In this short little sequence the makers of the video try to describe how color blindness affects his everyday life.

This was for an in-class film project class at Adelphi University. It’s an exaggeration of our classmate’s Michael’s life living with color blindness.

The video is categorized under Comedy, so don’t take it to seriously…

Color, What? What Color?

Meet with other Colorblind Women

During the last days I was contacted by colorblind women seeking other colorblind women to share thoughts, ask questions and just to talk. I was looking for a way to make it possible to meet and discuss. Finally I set up an own forum about color blindness here at Colblindor, where everybody can join and talk about color blindness viewed through colorblind eyes.

Color blindness in women is very rare. Only about 0.5% of all women have some kind of color vision deficiency and often this isn’t even recognized. Most people think color blindness is only man’s business – but that is wrong.

Because the biology behind red-green color blindness tells us, that much more men are colorblind (approximately 8%) this doesn’t mean that women can not be colorblind. Specially very uncommon cases like tritanopia (blue-yellow color blindness) and monochromacy (complete color blindness) are equally distributed among men and women.

Update: Because the forum was mostly a huge spam trap I removed it again. Sorry if any inconveniences arise through this.

Gymnast suffering Rod Monochromacy

The 18-year-old Alex Loch suffers from rod monochromacy. This is one kind of achromatopsia with a constricted over all vision.

The normal eye has rods and cones which support each other to see what we see. Cones are responsible for color and bright light conditions whereas rods are taking part in darker light conditions. Wich rod monochromacy your vision is determined solely by rods. Cones are completely absent or not working.

Alex Loch describes his vision conditions as follows:

  • complete color blindness
  • sensitivy to light and
  • restricted field of vision.

Despite all this he competed in Jr. Olympic National Championships as a gymnast.

It is fantastic to see how people can despite handicaps reach their goals.

Further readings:
Wikipedia: Monochromacy
Wikipedia: Rod Cell
Wikipedia: Cone Cell

Colorblind Painter

Miller is a painter and studying arts at the Wabash College in Crawfordsville, Indiana. And he is not just a painter but a colorblind painter.

It needs quite a bit of courage for such a decision. As a colorblind you know that you will never ever see the colors the same way as others do. There are no studies where you can learn it, nobody who can ever teach you. You will have to stick to it for the whole lifetime, knowing that you are always a colorblind painter and not just a painter.

“I have a more unbiased approach when I come into (painting). I don’t have the idea in my head of what would work with this, what would not. It gives me the option to experiment more.”

Through this a colorblind painter is not distracted by good matching colors or complementary colors. As Miller says, he can put more an eye on the action that’s created with different color combinations.

Or in other words: Don’t get distracted by your color blindness but try to turn it into an advantage.

Related articles:
Photographer with No Color Sense
Albert Uderzo’s Sight

Daltonism – Named after John Dalton

John Dalton was the first scientist to take academic interest in the subject of color blindness. He was born September 6, 1766 in Eaglesfield, England and died July 27, 1844 of paralysis. One of the first scientific papers John Dalton published was titled “Extraordinary facts relating to the vision of colours” and released in 1793.

John Dalton
John Dalton

Starting his career as a teacher he got interested in meteorology and mathematics. As Jonathan, his seven years older brother and John himself both were affected by red-green color blindness he also started some observations and researches about color vision.

“That part of the image which others call red appears to me little more than a shade or defect of light. After that the orange, yellow and green seem one colour which descends pretty uniformly from an intense to a rare yellow, making what I should call different shades of yellow”

He postulated that shortage in color perception was caused by discoloration of the liquid medium of the eyeball called aqueous humour. According to his research he believed that the aqueous humour was bluish and therefore filtered out all the colors. His observations and writings formed the expression Daltonism as a common wording for color blindness.

Through his lifetime John Dalton became a well known and respectable chemist and physicist and was one of the early proponents of the Atomic Theory. One of his last wills was to get an autopsy of his eyes after death. Unfortunately there wasn’t any bluish liquid found. It was his final experiment and proved that the condition called Daltonism is not caused by the eye itself, but some deficient sensory power.

Further readings:
WWNFF: John Dalton
Biography of John Dalton
Wikipedia: John Dalton
Notable Names Database: John Dalton

Related articles:
Mars in the Eyes of Colorblind Astronomer Schiaparellli
5 Misbeliefs about Color Blindness