As there are up to 10% of all men colorblind, you definitely will bump into one sooner or later. Or you just found out, that your old buddy is colorblind and you didn’t know it for that long.

To prevent you from putting your foot in it, I will offer you the top five questions you should never ask your colorblind colleague, partner, friend or neighbor. Why shouldn’t you ask those questions? Simply put: They just make you look like a fool and also make your buddy look like a fool.

Those five questions are not irrelevant. You should know the answer to those questions but don’t get them while asking somebody. Therefore I will not only list those five questions and leave them up to you but also will show you, why you shouldn’t ask each question and in the same breath answer them for you.

Color Blindness: Top 5 Questions Not to Ask

#1: What color is this?
Don’t ask this question, just don’t do it. This is something you make a colorblind person feel like a fool and you can’t take any profit out of it. Somebody suffering from color blindness doesn’t see other colors, they see less colors or maybe some colors closer to each other, because they see fewer differences in hue.

And if you would think about it before asking this question you will find out yourself: No answer given to this question will help you to understand how a colorblind persons sees the world. And that is actually what you want to know.

#2: Do you see only shades of gray?
There are very few people suffering from monochromacy. Those people only see in shades of gray. But they also have problems with bright light and need to wear often sunglasses.

This kind of color blindness is very very rare and there is only a tiny little chance, that your buddy will suffer it. So every other person suffering form color blindness sees colors, but less colors. With normal color vision you can distinguish more than 100 different hues. A colorblind person might only be able to distinguish 20 of them, but still can see colors.

#3: Which colors do you see then?
All colors, many colors, less colors. Nobody suffering from color blindness can answer you this questions correctly. Some may see more, some less but none can tell you which colors, because a colorblind person doesn’t know how you see the world.

If you nearly close your eyes your vision is comparable to colorblind vision. Also in the break of dawn the visible colors can be compared to what somebody suffering a color vision deficiency sees.

#4: Who buys your clothes?
Me; who else? Yes; going shopping for a new shirt and tie isn’t the easiest thing for a colorblind guy. And it’s sometimes embarrassing, not to know if the chosen colors fit together and fit into your wardrobe. This is something that accompanies you for your whole life if you are colorblind.

There are different strategies to handle this. Either you ask somebody else, every time until you just know the pieces which fit together. Or you adjust the colors you wear to colors you know that they will always fit together.

#5: Hey; you shouldn’t drive a car!
I know, this isn’t really a question. But it transfers to the question in your mind: How can a colorblind person distinguish between the red and the green at the traffic light?

Usually this is not a problem at all. The chosen colors for traffic lights are enhanced to make them more visible to colorblind people. Some extra orange and blue are mixed in, so everybody should see the difference. An other clue which helps a lot is the arrangement: Red at top/left, green at bottom/right. All this together minimizes the problem for somebody suffering from color blindness almost to nothing.

So don’t put your foot in and make yourself a fool. Try to ask some interesting questions which can get you into a nice and interesting talk about color blindness. I’ll have a look at such intelligent questions in a future post. Stay tuned.

The reader question below points out a very delicate topic. Not everybody wants to admit to others and even more importantly to himself, that he or she is colorblind. And because color blindness is not something which is obvious and you know anyway like your height, it’s not easy to find out if such a person really is colorblind or not.

How can I tell if my friend is color blind? Are there certain colors he will wear or certain things he will do? I think he might not want to admit it, but I wonder. I am afraid to ask. I don’t want to hurt his feelings.

As written in the question, somebody confronted with a maybe colorblind person, which doesn’t like to talk about it, is in a uncomfortable position. Should you start talking about it and ask? Or should you just sit back and wait until you’ll find out anyway?

I will offer you two different ways to tackle this impasse. As I recommend the offensive way warmly to you, the defensive way can be an equally valuable path for you to follow along.

But before we dig into some possible solutions, we have to have a closer look at the term colorblind. As there are many different types of color vision deficiencies, it’s important to know what we think of when saying my friend is colorblind.

By far the most common form of color vision deficiency is red-green color blindness. About 8% of all men are suffering some type of it. Actually red-green color blindness can be split into four different subtypes. But all of those have a lot in common:

• Red-green colorblind people can see many colors but differentiate them more in terms of brightness and saturation than hue.
• The color axis red-orange-yellow-green-brown is the most challenging if you are suffering it.
• There is also a line of colors ranging from blue-green to gray and over to some purple hues which are difficult to tell apart.
• If you are suffering only a mild form of red-green color blindness you might even not be aware of it.
• A lot more men than women (< 0.5%) are affected.

There are some other types of color blindness, however they are only very rarely observable. Knowing this basics lets us reformulate the question to the more precise statement:

How can I tell if my friend is red-green colorblind?

The Offensive Way: Ask him.
I know, this doesn’t sound like the right way to you. But it’s definitely the best way. Let me tell you why and how you can do it.

First of all you have to learn about color blindness as a not colorblind person. You will find a lot of material about it on Colblindor or on the web. Some interesting facts are:

• Color blindness can occur in very mild forms which are no handicap in everyday life.
• Colorblind people often have problems to match the right clothes, know when a fruit is ripe or if they have a sunburn.
• If you are colorblind, you often can’t spot red/orange/yellow blossoms and flowers.
• There is no cure for color blindness but most people easily learn to get along with it without feeling handicapped.

If you learn more about the challenges of a colorblind person, you can offer appropriate help. You not only have to wait every time until you get asked (or often not get asked) but just help out as it would be the most normal thing. This can be a great support for a colorblind person, for example in a shop when he likes to buy a new cool tie which of course should match his shirt.

Through your knowledge about color blindness you can go the offensive way and ask him. But not only ask if he’s colorblind, he might not even know it. Tell him, how you could support him much better in some everyday tasks and how it could help you a lot more to understand how he sees the world.

You might like to ask him to have together a look at some color blindness tests and find out if he has some deficiency and how severe it is.

Color blindness is nothing to be ashamed of, there are to many of us.

The Defensive Way: Don’t ask him.
Often you really feel to afraid to ask or you don’t want to hurt his feelings. Therefore I would like to explain you some ways which might help you to find out if your friend is colorblind or not.

Shopping for Fruits. A colorblind person often has problems distinguishing a ripe fruit from a unripe or even an overripe one. If he often buys unripe bananas this might be a clue.

Matching Clothes. If you are colorblind you can not match your clothes very well. You can’t see which colors do match and therefore often either wear only few colors like black and white or otherwise wear sometimes clothes which do not match in color at all.

Pastel Colors. I can’t tell you why, but colorblind people tend to prefer pastel colors. Not always, but more often then people with normal color vision.

Colored Crayons. A huge box of colored crayons, this is some of the worst which can happen to somebody suffering from color blindness. Usually a colorblind person chooses a small box of color crayons with not to many distinct colors which are always in the same order and well distinguishable.

Colorful Flowers. When wandering around or in your own garden, if you are colorblind you definitely will have some problems spotting nice flowers and blossoms. Usually from the distance you wont see them; everything might look green to you. Only coming closer or if your friend tells you about them, you will be able to see for example red or orange flowers.

Cooking Meat. If your friend is colorblind, he also will have some problems to tell if meat is cooked well just from the color. The color change is usually to small to spot and he often will ask somebody else for a judgment.

Skin Color. Colorblind persons have problems to see slight changes in skin color. They don’t see if somebody goes pale/green and looks sick or if he has a sunburn or not.

Maybe through this seven hints you will be able to find out if your friend is colorblind or not. If you have the strong feeling, that he really has some type of color vision deficiency I would like to encourage you also to think about the offensive way and finally ask him.

I hope this tips were of some help to you to find out about the color blindness of your friend or just to learn more about your colorblind partner. Maybe you also would like to know How to Support Your Colorblind Husband which includes some more advises how to handle color blindness if it doesn’t affect you yourself but your partner, friend, workmate, …

To be colorblind is one thing. To know which type of color blindness you are suffering from is something different. Particularly red-green color blindness, the most common form of color vision deficiency, has several subtypes which are not easily distinguishable.

Yesterday I received the following question which I would like to quote here and hopefully give you some answers thereafter.

My husband is red-green colorblind, but we don’t know which type. What is the best way to go about finding out protanopia/protanomaly or deuteronopia/deuteranomaly? We’ve seen some of the test on the internet, but what do you recommend?

Maybe you are in the same position as the person described above; so let us dive in and find some answers for you.

Before I give you some advice on the how and why I would like to explain the technical terms above and set them into relation to red-green color blindness.

Red-green color blindness terminology

There are two different axis which you have to take into account. The first axis distinguishes if you have problems with your long (L) or medium (M) wavelength cones. The L-cones are red sensitive and are—if malfunctioning—the source of red-blindness (protanopia) and red-weakness (protanomaly).

On the other side are the M-cones, which are more sensitive to green colors. If your M-cones are absent or not working properly you are either green-blind (deuteranopia) or green-weak (deuteranomaly).

The other axis tells you about the severity of your color vision deficiency. Either you are a dichromat (protanopia/deuteranopia) and therefore you have only two different types of color receptors in your eyes. Or you have three different types of color sensitive cones, like somebody with normal vision, which is called anomalous trichromacy (protanomaly/deuteranomaly).

Finding out your subtype of color blindness

If you want to know for sure on which sides of the axis your color blindness sits, you have to go to a doctor for a check-up. But not just any doctor can do the job for you. Before your consultation you might like to check the following two points:

1. Your doctor should be an eye specialist.
2. He should have different possibilities to test for color blindness (check this in advance).

There are different color blindness tests available and every test has its advantages and weaknesses. If you put everything just on one test you might get a wrong conclusion. The list below gives you an impression of what tests could be available when taking your tests at an eye specialists place.

• Pseudoisochromatic plates like the well known Ishihara plates tests.
• Anomaloscope; Neitz-, Nagel- or also Heidelberg Multi-Color-Anomaloscope.
• Lantern tests as the Farnsworth LT or the Holmes-Wright LT.
• City University tests.
• Arrangement test like the well known D-15 Farnsworth or the Farnsworth-Munsell test.

Every single test can play its part when you want to find out which subtype of color blindness affects you. Different tests together will give you an overall picture and a very good and reliable result when properly accomplished.

If you have your reasons not to go to an eye specialist you can try to do some color blindness tests by yourself. In that case you have to know, that these results will never be as reliable as when you consult your doctor. You also may not have the possibility to do many different tests like the ones listed above, as they are not publicly available.

There are many places where you can buy such tests like the Ishihara plates and accomplish the test at home. But this is usually way to expensive and as you are not trained in interpreting the results I don’t recommend it to you.

On the other side you can take some online color blindness tests. Before you head on, take your tests and think you know what subtype of color blindness is your one, let us step back and have a look at the difference between an online and a hardcopy test.

1. Online tests are often scanned images. Because printed and display colors are very different and each scanner has its own color calibration, this images can look quite differently on screen. Therefore the results would not be the same and are less reliable.
2. Every computer display is different. So if you take an online color blindness test using different displays the result could also vary.
3. A computer display has a so called gamma correction. If contrast and brightness of your monitor or not very well adjusted this could also alter your test results.

Being aware of all that you can head on and try out some tests to find out more about your color vision deficiency. To get a more detailed analysis of your red-green color blindness I recommend you the three following steps.

• Step 1: Take the Ishihara plates color blindness test and if this one is not enough check out the other source about Ishihara plates test. Through this pseudoisochromatic plates test you get an overall feeling of your color blindness but not a very accurate result.
• Step 2: Take the color blindness test based on confusion lines. There are three different tests (protan/deutan/tritan) to choose from and when you write down your results you get a good understanding of which subtype of color blindness gives you the biggest problems.
• Step 3: Take the D-15 Farnsworth Arrangement Test. These results will tell you more about the severity of your deficiency. If you have real problems accomplishing the D-15 test you are most likely a dichromat. Otherwise you supposably have a anomalous trichromacy.

Combining together the results of those color blindness test should give a more accurate knowledge about your color vision deficiency. Through step 2 you should be able to place yourself on the red-green axis. Either you are more on the red side (protanopia/protanomaly) or on the green side (deuteranopia/deuteranomaly). But be aware, if you have problems with one of those tests you will also have some problems with the other one, because the confusion lines of red- and green-blind or -weak persons are very close together.

Step 3 tells you more about the severity. If you are a dichromat and therefore have only two distinct types of color receptors in your eyes, you will have severe problems to accomplish the task arranging the colors in the right order. Otherwise you most likely have some weak form of color blindness. This shows you your position on the second axis.

Putting together step 2 and step 3 should give you a quite good overall impression of your color blindness. But as I said, there are many limitations to be taken into account and no online test will ever replace a consultation at the eye specialist.

I hope I could reveal some insights about red-green color blindness and help you to find out more about your color blindness in detail. If you did like this article you can either bookmark it with the button below or subscribe to my RSS feed to get fresh updates on color blindness.

It’s not always easy to live with your color blindness. One special case are all those color coded wires.

I recently came across this problem, when I tried to elongate a telephone cable. This can be a big problem if you are colorblind and have nobody around who can tell you which color is which and has to be connected to which port.

Brandon describes a similar problem while he was rewiring some cables in his house. He vent his anger in When Color Blindness Sucks.

What do we learn:

1. Don’t work with color coded wires if you are colorblind.
2. Because almost everything is color coded these days, stop working at all.
3. Ask the government for support because you can’t work.
4. Sit back and think what you could do in your spare time.
5. Maybe some new rewiring of your cables at home?….

Dear colorblind fellows, do you have similar experiences with color codes?

Most people connect the term color blindness to blindness and color, which tells them, that if you are colorblind you can see only black and white or maybe grayscale pictures. Only when they talk to somebody who really is colorblind or read something about color blindness, they find out, that they are wrong.

Color blindness is just the most common term for describing all different types of vision conditions which relate to a less broader color spectrum. If you are affected by color blindness you can see less colors than a “normal” human being but not none.

If we have a look at the terminology there are three different well known terms to describe this disability:

• Color Vision Deficiency: This is the most accurate term. It is mostly used in scientific papers or from doctors. It describes the actual handicap to the point but it is not well known in common speech.
• Daltonism: This term is derived from the 18th century researcher John Dalton. Himself colorblind he did some investigations and described the phenomenon for the first time in a scientific paper. The naming is still used in some languages and is also related to all types of color vision deficiency.
• Color Blindness: This is the most common term although it is misleading. Maybe it made the run in common speech because it’s just easier to say “he is colorblind” than “he has a color vision deficiency”.

All three terms relate to the same phenomenon: People or animals who can’t see colors as “normal” human beings can see colors.

Maybe we need to have a quick look at how a “normal” human being actually can see. If you are not suffering from a color vision deficiency, you have three different cone types inside your eyes. Each of this has a special color spectrum it relates to and sends signals to the visual system. All three signals, which can be stronger or weaker, are mixed up to one distinct color inside your visual system.

If you are colorblind usually there is something wrong with one of those different cone types. Either they are faulty or missing at all. This means you still can see colors but less. Maybe less diverse, less shades, less colors and definitely less colorful. But not to be mixed up with a black&white picture. Those are only grayscale pictures or looked at it differently – brightness pictures.

Colorblind people can see colors. They can see blue and violet, green and yellow, red and orange and a lot more. Maybe just a bit less colorful here and a bit less colorful there, which makes them having bigger problems to distinguish colors. But anyway, they definitely can see colors.

First of all, why should I battle color blindness? Usually your genes decide if you are colorblind or not and this you can’t change for your whole life (at least not until today). That’s why you just have to accept it the way it is. But on the other hand, why not try to compete it and try to overcome the handicap.

If you are suffering from any kind of color blindness you know that this handicap follows you through everyday life. In the supermarket when you buy some fruits or vegetables, at the office when you read the newest diagrams of your sales figures and even at home when you try to choose the right tie for the candlelight dinner with your new girlfriend (approximately 8% of men and only 0.5% of women are affected by color blindness, therefore it’s more likely that you are a colorblind man than a woman).

So why not make life easier and try to overcome this burden. You could just try to learn colors by heart. Remember a color and its name every time you see/hear of a new one. This is like learning new words in a foreign language, the first step isn’t that easy to take but after a while it should get easier learning new colors.

Sadly this doesn’t work for me. I can’t learn a color on a shirt and then fit this color next time when I buy a fruit at the local store. Of course when you once know the color of your shirt you, well, know it. But you just can’t transform it to something else. Not even to another shirt at a clothes shop. So this attempt failed.

Let’s make another effort and take pictures. Pictures on a small digital camera. A camera which you can take easily along with you in your trouser pocket. This gives you the ability to compare the picture gallery with a thing you don’t know the color yet. Just find the best fit and you know it. This way you even get a growing archive of colors to fit and are therefore less helpless when you should buy knew trousers and don’t want to ask the young beautiful shop assistant who is approximately twenty years younger than you.

I know, this is also not a breathtaking idea. Let’s go one step further. Look around for a not colorblind girlfriend. A small lightweight which you even could carry in your bag. This way you have your color matching voice always along with you. You will never bite in a green banana again…

The conclusion out of this is that not the colorblind persons have to battle color blindness but the color viewing persons. They should think more actively about it when drawing a diagram, preparing a presentation, designing some new color codes or developing a new product. And this also means to me that the industry has to take into account that almost every tenth person has some kind of color vision confusion.

Think about it.

Yesterday I went shopping. First I needed some fruits whereas I always encounter the same problem: Are the bananas already ripe or still green? At a first glance I couldn’t tell the difference and I didn’t like to ask a shop assistant or bite into a green banana at home. That’s why I took out my brand new ColorLuminator, held it onto the banana and pressed the one and only button. In an instance I could read the correct color on the built in screen. They are yellow. Great, I’ll take them.

Afterwards some cloth shopping had to be done as well. I needed some new shirts. My wife said I could buy a very fashioned purple one and a light green which would fit to my new trousers. So I went to the shop and had a look around. But there were so many shirts to choose from, which would usually be a very hard decision and often a lucky strike with my color blindness. And I was not in the mood to tell the story of my color blindness to the salesclerk. Again I took out my new favourite device, the ColorLuminator, pointed onto some shirts and found with its help the sought-after purple shirt.

On my why home the sun light was shining directly into the traffic lights and I couldn’t see if red or green is glowing. But again with the help of my ColorLuminator I made my way home safely.

Wouldn’t it be great? Great to have such a tool. Unfortunately this is not true yet. You can’t buy a ColorLuminator in the stores today. But Ian Cannon, a 17 year old student from Sydney, developed a tool like this and is on the way to maybe win the Nescafe Big Break, a big prize for young entrepreneurs. With the help of publicitiy and the money he could maybe make a dream come true and develop the ColorLuminator for the mass market. He was already thinking about this idea when he was 12. But only when he understood how to measure color he could start developing his Luminance Contrast Device.

I am looking forward to see some kind of tool like this ready to use. It could be of great help for people suffering any kind of color blindness. And maybe, if we look even further into the future, the ColorLuminator could be built into your glasses and show the name of the color you focus on directly on the glass itself. Wonderful.

Further readings:
Nescafé Big Break: Finalists 2006
Hot recipes for niche success

Related articles:
Green Bananas
Shopping for my Boy
Walk – Don’t Walk

You can read some thoughts from Tom Coates at On the perception of the colours of Mars… He put a nice littel theory into the room and received quite some comments and a nice discussion around the topic.

The core of his theory goes like this:

…if we had evolved on Pluto, Jupiter or Venus, we’d perceive different wavelengths in more depth and with more variety. In fact, potentially if we’d been born on Mars, it would look to our eyes like a vibrant and colourful place, while Earth could look comparatively drab.

Reading through the comments you can learn a lot about color perception in our solar system. And also the posted links reveal a lot about the topic and let you dive even deeper into it.

And what about us colorblind?

Were we just born on the wrong planet? Maybe we would be the big guys with great vision on some other planet. For each kind of different color blindness there is out there somwhere a planet waiting. And because we are not yet ready to colonize other planets we (the colorblinds) are maybe just ahead of our time.

This is another clue to me that we colorblind people are one step ahead compared to our opponents, the not colorblinds ;-)

Related articles:
How the World is seen through Colorblind Eyes
Colorblind Peopla are Wise
Colorblind People are Dumb

Thanks to Helena from Bitter Poison for telling me about this article.

Laser pointers are often used in presentations to show the hot spots or a part of the slide which the presenter is talking about. Most often people don’t know about the drawbacks concerning colorblind members of the audience when using laser pointers.

If you are not affected by color blindness the little red or green spot which is produced by a laser pointer can not be overseen. The little dot is so bright, shiny and clear that your eye easily finds it. Even following the light if it is moved quite fast isn’t a problem at all.

Now if we look at it through colorblind eyes this looks totaly different. Maybe this affects only people with red-green color blindness because of the color used in laser pointers. The laser pointer spot just isn’t that much outshining to colorblind people as it should be. Therefore it is very hard to follow the point – or often it can’t even be seen at all.

Intensive laser pointer usage combined with fast movements can make it very demanding for people affected by color blindness to follow a presentation.

Here are my suggestions to you for the next time you are doing a presentation. If you use a laser pointer and want to make it an enjoyable experience equally for all listeners follow these three guidelines:

1. Hold still. Don’t move the laser pointer every time you start explaining something but hold still for a few seconds. This gives the listeners enough time to find the spot and see what you would like to emphasize.
2. Move slowly. After hold still you can start moving, but do it slowly. Often presenters are moving much to fast and through this some persons are loosing track of the point.
3. Say what you show. Forget the words here, there, over there and so on. Label it correctly like on the upper left side or the first part of the diagram. Through this your audience knows what you are talking about even if they can’t see the laser point.

Laser pointers are a great tool because they are very handy and can be used to point out things which are way up or on the other side of where you stand. But don’t use them like a lightsaber. Use them smart and well directed. Don’t let the laser pointer lead you but lead the laser pointer.

Related articles:
Colorblind Population
How the World is Seen through Colorblind Eyes

While surfing the web I came across the following article and because it is in someway related to color blindness I decided to reproduce it hereafter:

Next time you have a meal, look at your plate – what colors do you see? If its mostly white and brown then your diet might be colorblind!

In order to have a healthy diet you need foods from all the food groups and that means a colorful plate. Just eating meat and potatoes won’t provide you with the essential vitamins and minerals you need to stay in your best health – you need to add in colorful fruits and vegetables!

If you want a good balanced diet, here’s some colors you might want to see next time you look down at your plate:

Green
Green colored foods like peas, kale, spinach, honeydew melons, kiwifruit, dark leafy lettuces, and leafy greens contain lutein which helps maintain good vision and can help reduce the risk of macular degeneration and cataracts.
Another green group includes broccoli, cabbage, bok choy, swiss chard, brussels sprouts, rutabaga, turnips, cauliflower, and watercress. These foods contain indoles, which can help reduce the risks of cancer and reduce tumor growth in cancer patients.

Yellow
The yellow orange colored food are high in bioflavonoids, which work in combination with vitamin C to help reduce the risk of cancer and heart attack. They also contain powerful antioxidants and help maintain healthy skin, strong bones, and good vision. The foods in this group include oranges, tangerines, pears, lemons, nectarines, grapefruit, peaches, apricots, pineapple, pineapple, yellow raisins, and yellow peppers.

Blue and Purple
Blueberries, purple grapes, blackberries, black currents and elderberries contain Anthocyanins which can reduce the risks of heart attack, cancer, diabetic complications, Alzheimer’s disease and age-related memory loss. Dark purple foods contain phenolics, which are powerful antioxidants and can help to slow the effects of aging.

Orange
Dark orange foods like pumpkin, sweet potatoes, apricots, peaches, carrots, cantaloupes, mangoes, and butternut squash contain beta-carotene, a powerful antioxident that can help keep your immune system healthy as well as maintain good vision and can even aid in reducing heart attacks and cancer.

Red
Tomatoes, guava, watermelon and pink grapefruit are all red colored foods. These foods contain lycopene which has been much publicized lately as helping to protect against prostate cancer. In addition, these foods can help reduce the risk of breast, and skin cancer as well as reduce the risk of heart attack.
Red onion, cherries, kidney beans, raspberries, strawberries, cranberries, beets, red apples (with the skin), and red cabbage contain anthocyanins, powerful antioxidants that can help control high blood pressure as well as reduce the risks of cancer, heart attack, Alzheimer’s disease, and diabetes complications.

One way to get a colorful plate at every meal is to try to fit in 5 servings of fruits and vegetables every day. Try to include food from all these color groups at least once during the day and you will be surprised at how much your health improves.

Lee Dobbins writes for the A2Z Vitamin And Herbs Guide For Natural Healing where you can find out more about vitamins and herbs as well as natural healing methods.

Source: High Quality Article Database – 365articles.com
Photos taken by Esther Perez – Some rights reserved