Colorblind Men Suffer under LED Lights

I’ve got a laptop and I’m writing this story down on it right now. It has three little LED lights shining steadily and one blinking on an USB device. But which color are they?

A lot of LED lights are used to show you different states of just anything. Either its on or off, connected or not, loaded or empty, working or on hold, not loading or loading, and more. Right now I can think of several devices in my household which have LED lights on them to show me just anything and everything: stereo, router, electrical toothbrush, electrical razor, sawing machine, digital camera and of course my laptop.

Red and Green LED

Red and Green LED by Sebastian Yepes

All of those LEDs want to tell me something, but I can’t see it. Due to my color blindness I just don’t see the difference between those green, red, orange and yellow shades. I can distinguish the blue ones from all the colors above, but this combination is unfortunately not often used.

Have a look at this very nice picture taken by Sebastian Yepes F. He says that this picture is made by a red and a green LED light. I can’t see them.

I mean, I can see the colored circles, but aren’t they in some shades of orange, or maybe yellow, or—oh I don’t know.

LED Rainbow

LED Rainbow by Andrew Hoyer

Or this nice rainbow taken by Andrew Hoyer. Shall I listen the colors I can see: red (or brown?), red (or orange or what?), green (or yellow or still orange), then brighter blue, blue, darker blue.

I definitely like the first three. Unfortunately this are the ones most often used inside electrical devices—which are not designed for the colorblind.

So dear manufacturers of things including LED lights which should tell me something: Please either use blue combined with yellow, which should be differentiable by everyone, or use blinking and non blinking LED lights. Colorblind persons have huge problems with all those little lights in green, yellow, orange and red. And as there are up to 10% of all men colorblind, this is definitely something to think about.

By the way, I never know it the batteries are loaded on my laptop or not just by looking at the battery LED. I either just plug it long enough or ask my not colorblind wife :-)

Stroop Test – Can You Read the Colors?

In case you’re not colorblind, naming a color is an easy thing. But naming a color if it is a colored word of another color name (e.g. green) is definitely not that easy to accomplish.

Stroop Test

Stroop Test

The Stroop Test was described by John Ridley Stroop back in 1935. He took some color names and just colored them differently. Try it out yourself with the graphics below. Don’t read the words but say aloud the color names you see.

Did you do well? Even if you have normal color vision, after the first two lines you start struggling because the wrong names are very distracting. And how did you perform, if you have some type of color blindness?

For me it looks interesting and I can see some differences in the colors. But it’s definitely just a guessing game. Colors I can almost not distinguish and therefore have big problems to name them in this graphics are:

  • BluePurple
  • OrangeGreen

Do you know, what I like the most about this? It’s the color Red I can spot easily, despite the fact I’m red-blind…

Colors in Your Life

Which are the most powerful colors in your life? Do you have any at all or are they changing from time to time?

Tell your story and join the next issue of Carnival of Colors. This carnival includes anything in anyway related to colors. So don’t wait and write your point of view concerning this broad topic.

My favorite colors are a grass green and a sunflower yellow. I also enjoy blood red or a very dark tree-leaf green.

The next issue of the carnival will be published first of July. This time the carnival host is Mike from 10,000 Birds. Thanks Mike and a warm welcome to all the friends of birds in the world of color blindness.

If you like to join, just contact me including the link to the article you wish to be included.

Day of Links

Today I found two links I would like to share with you:

The first one is from Chris, the writer behind Mixing Memory. He had a closer look at the Color Opponency in Synaesthesia. People with Synaesthesia perceive colors even when looking at black letters and numbers. Some researchers discovered now, that if you show such persons wrongly colored color-names (e.g. red) they have very different reaction times than people with no Synaesthesia.

The second link is for web publishers. Skye claims that you have to Check Your Link Colors – You May Need to Redecorate! This is not only true for professional web designers but also for any blogger running a free blog software. If you are interested in accessibility you might enjoy her weblog about all access blogging .

Monitor Simulates Colorblind Vision

There are many tools available, on- and offline, which show you how a web page or image is seen with a color vision deficiency. These software tools are great and should be used by every web developer.

FlexScan S2411W

FlexScan S2411W with Color
Vision Deficiency Simulation Capabilities

Eizo went even one step further and introduced this simulations into some of their LCD monitors as a hardware solution. This gives you a realtime transition, which doesn’t need any CPU time and is working even with fast moving movies.

They introduced two different simulations: One for red-blind persons (protanopia) and the other mode is used to simulate green-blindness (deuteranopia).

Protanopia and Deuteranopia Simulation in Real Time

Simulates two types of red-green color vision deficiency – protanopia and deuteranopia. The FlexScan S2411W does all the color conversion processing in real time – even moving images. With the bundled UniColor Pro software (Windows Vista/XP/2000 and Mac OS X 10.3.9 or later only) – also developed by EIZO – the designer can instantly switch from a normal viewing mode to the Protanopia and Deuteranopia viewing modes.

Up to now the system is implemented in the models FlexScan S2411W, FlexScan L797-U, and ColorEdge CG241W.

It would be nice to see one of those monitors with the color conversion processing in action. Especially a comparison to some good software simulation tools could be very interesting and show if Eizo can really deliver what they promise.

ColorBlindExt – Better Web Accessibility for Colorblind Users

Have you ever wondered, if you can’t see certain things on a website because of your color blindness? This time is over now—at least for colorblind Firefox users.

The Firefox add-on called ColorBlindExt was released just recently and is a great support to discover things which you couldn’t see up to now. The developers describe it as follows:

This extension helps color blinds while browsing the web, by processing images and text on the page according to the type of user’s color blindness. Color Blindness detection test is included for creating awareness among people.

After installation (see further down) as a first step you should take the color blindness test available through the newly added menu called ColorBlindExt. The test is based on Ishihara plates and will tell you, which type of color blindness you are suffering from. It detects protanopia, deuteranopia, tritanopia and even monochromacy, which means you are completely colorblind.

After taking the test the filter will be set according to your results. This can be changed at any time. Also the filter can be completely enabled or disabled however you like.

ColorBlindExt - Filtered Image

ColorBlindExt – Filtered Image

ColorBlindExt lets you choose to filter whole pages. This can be done either automatically or through the context menu, clicking with your right mouse button anywhere on the page and choose Filter page.

On the other side you can only filter images whereas a little window pops-up, showing you the filtered image by itself.

Personally I like the image filtering on demand. Through this option, which is also available on the context menu when clicking on an image, pictures and diagrams can be enhanced according to my type of color deficient vision.

The developers took the image filtering even one step further. Through the settings you even can adjust the level of deficiency and a choose from a noise reduction and sharpening option. This lets you play around and find the settings which fit the best to your personal color vision.

The tool also has some limitations, which don’t really restrict the usage to me when I look at them.

  • Page contents like flash objects, applets, media players can’t be filtered, it is out of scope.
  • Only elements accessed by DOM are processed.

Unfortunately the installation isn’t a single click and run. I tried to summarize all requirements including the links to get the latest software if you are missing some of them. I hope this helps you to get your colorblind webpage filter up and running without a hassle. Be aware that you need administration privileges if you have to install new software like the Java runtime environment.

Installing ColorBlindExt in 5 Steps

  1. Firefox
  2. Java Runtime Environment
  3. Java Advanced Imaging
    • Version: 1.1.3 or higher
    • Check: Start → Settings → Control Panel → Add or Remove Software
    • Download: java.net – JAI for JRE
  4. Firefox User Registration
    • Why: ColorBlindExt is not yet available as a public download. It is accessible through the Firefox Add-ons sandbox, which is only open for registered users.
    • Registration Form: Firefox Add-ons: New User Registration
  5. ColorBlindExt

Hopefully this tool will help you to access some websites more easily than before or to read some colorful and up to now undistinguishable chart lines. And I also hope this tool isn’t used as an excuse for web designers to disregard accessibility, especially concerning color blindness.

Looking for Children Games Playable with Severe Color Blindness

Keren contacted me, because her son is severely colorblind. He can’t really play basic games as every children game is in color.

What she is looking for are some board games for her eight year old son, where he could pick up the enjoyment of playing games. Because everything heavily relates to colors, this is not an easy task to accomplish.

I have a son that is colorblind with red, green and blue. He can see colors which have a yellow base. This has made it very hard for him to play basic games as every childs game is in color. I have tried every resource in aid to get him the simplest game and now am writing to you to ask if you know or have any games to your knowledge that he would not have difficulty in playing. His age is 8 and has never done jigsaw puzzles, or played board games.

Concerning the color blindness of her son we could at least find out a bit more of what type he is suffering from. This is important because for you, as a mother or father of a child with a color vision deficiency the first step should always be to try to understand what your child really sees. With this in mind it’s much easier for you to help your child and for your child to tell you about his/her problems.

After asking for more details she wrote me the following sentences. They show us some nice insights what it means to live with a colorblind child.

My son has never spoken in color names and as for his crayon box I have had to label every color. With all his school writing books I have to photocopy in black in white as he is not able to see the pale blue lines he is meant to write on.

All this descriptions point into the direction of some kind of achromatopsia. People suffering from some type of achromatopsia have at most one type of color receptors they can perceive colors through. Therefore they see either only in shades of gray or, when suffering from blue cone monochromacy, can see at most some shades of blue.

This of course means, that children suffering from achromatopsia can only play games which don’t rely on colors. Or the colors must at least be easily distinguishable when transformed to shades of gray. Here is a tip how you could test this:

  1. Take a digital picture of all the game pieces.
  2. Upload the picture on your computer.
  3. Transform it to a grayscale picture (most picture programs support this like the free available Picasa from Google).
  4. See if you still can distinguish all the different parts of the game.

Unfortunately I don’t have that many children games and don’t know of any which are playable even with the handicap of not perceiving colors.

Do you know of any games? Please add your ideas in the comment section to help not only Keren but also all other mothers and fathers facing the same challenge.

Colorful Peacock

I enjoy going to the zoo very much. And as we are a big family now we even have a season card for the local zoo.

Christopher wrote about Finding Color at the Zoo. So what does a colorblind guy do with his camera handy and looking for some nice shots to take? – He is also looking for colorful pictures; even if this sounds a bit contradicting.

Here is the most colorful picture I took at my last visit. It’s the very colorful eye on the tail of a peacock.

Peacock Eye

Peacock Eye


And here are the colors I can perceive through my colorblind eyes. Starting from the middle going outwards.

  • very dark blue, almost black
  • dark blue
  • light blue
  • reddish-green or brown?
  • yellow
  • again a light blue

Now it would be interesting to know: How far away are my colors from to the reality? And what colors do you see?

Market Research on Internet Accessibility

Criteria Fieldwork Logo

Criteria Fieldwork

Adam from Criteria Fieldwork contacted me today. They are looking for people who would like to join a market research study into internet use, and it’s accessibility for individuals, who have certain impairments, that may or may not effect their use of the web.

Specifically they are looking for the following types of people:

  • Visually impaired individuals.
  • Individuals who have Dyslexia.
  • Individuals that have mobility impairments.

I suppose at least some readers of Colblindor best match into the first group. Unfortunately I’m not living on the island and as the interviews take place in a North London location, or in your home/office close to this, I can’t join. But maybe you have some time this Thursday 14th, Friday 15th and Monday 18th. The research will consist of one-to one interviews that will last up to one hour.

Not forget to mention you get a thank you cash out of £40.00.

Unfortunately it is the nature of market research that we are unable to disclose the end goal/ purpose of the research to potential. As we like each participant to have an un biased approach when taking part.

So we won’t find out more about this study. But if you like to see what it is all about and are living in the area, just either add a comment to this article or contact me directly. I’ll get you in touch with Adam.

Police Officer – Does Color Blindness Matter?

“Can I become a police officer even when I’m colorblind?” This is a common question among colorblind young men, when dreaming about a career at the police department.

This article will tell you, if color blindness really matters when you want to become a police officer. First we will have a look at some main factors and possible test methods. After that you will find out more about local regulations concerning color vision and some actual job offers seeking police officers. An in the last part of this article I will list your 6 steps you have to walk through to become a police officer despite your color blindness—or at least to make sure you check all your possibilities.

Imagine the following situation: A police officers witnesses a theft and reports it to the police station. “The suspect is about 35 years old, has brown, dark-brown, no black hair. A orange, I mean green shirt; or was it yellow-red. And blue, almost blue, kind of blue trousers. Skin color—oh don’t care about.” I know, it doesn’t have to be like that if you suffer a mild color blindness. But with some types of severe color vision deficiency this statements are coming closer to the truth than not.

Color blindness is not a definite no go for becoming a police officer, but it’s certainly a big handicap. Before we have a closer look at the topic and the differences in some countries and police departments, you might like to read this story of a colorblind police officer and his personal career.

If you are suffering from some kind of color vision deficiency and want to become a police officer, there are several factors to be considered.

  • Type of color blindness. There are different types of color blindness. The strongest form is called achromatopsia, whereas you can only see in shades of gray. This would certainly disqualify you from being a police officer. For the other types like red-green and blue-yellow color blindness it mostly depends on the factor listed next.
  • Severity of color blindness. Is it only a mild form of color blindness or are you a dichromat, who have only two different color receptors compared to three with normal vision? Mild forms of color blindness are often not even recognized by the person concerned. Only by taking some tests, they’ll find out about it. It definitely depends on the severity of your color vision deficiency, to make a judgment about your fitness to be a police officer.
  • Local recruitment regulations. Different countries, states, cities or police departments have sometimes different recruitment regulations. Most often this includes also some restrictions concerning color vision ability. Check your applicable regulations.
  • Recruiting staff. And last but not least, it depends either on the person who is recruiting you or on your new boss. In the end they will decide, if you are the right person for this job or not. Maybe if you just fit in, they will bend the rules to your advantage.

If you apply for the job as a police officer, this will almost ever include any form of color vision test. Most often this is done with an Ishihara plates test, but also Farnsworth tests and City University tests are in use to test your eye sight concerning color blindness.

Often people say, they just cheat on those tests and that will do it. I think, this isn’t the way to go. What, if they find out afterwards, or you annoy your partner because you can’t see the colors you should? And what if they will find out during the test, because cheating isn’t always easily done? I recommend to just be yourself. If it is the right job for you, you will find your way with legal methods.

I would like to point out some regulations and job offers I found. You will see, that there are different wordings used when talking about color vision ability and it’s not always obvious what it really means.

Color Vision Deficiency Regulations for Police Officers

To start with I would like to point out this story of a colorblind police officer applicant written down by a chief of the Berkley police department. It shows very nicely, that it’s not always easy to make a judgment and that there are possibilities even for somebody with a color vision deficiency.

In the United States, the New York State Police writes in their qualifications notes, that color blindness is disqualifying. The Washington State Patrol Trooper formulate it with ability to distinguish colors and be free of color blindness and night blindness. A bit less restrictive is the formulation used for recruiting at the Los Angeles Police Department: Candidates must be able to accurately and quickly name colors. A whole battery of tests has the City of Falls Church requiring that Candidates must pass near vision, color blindness, darkness perception, night vision, and peripheral vision tests. And on the other side we have the very concise formulation NO color blindness of the Portsmouth Police Department.

If you jump over the Atlantic Ocean and have a look at some regulations concerning the recruitment of police officers in the United Kingdom, it looks a bit different. According to policies of the Police Service of Northern Irland, an applicant must have 7 out of 10 correct replies in the City University Colour Vision Test. The detailed eligibility requirements for color vision of England and Wales read as follows:

Monochromats should be rejected. Mild anormalous trichromats are acceptable and should be treated as normals. Severe anomalous trichromats and dichromats are also acceptable but should be instructed in coping strategies.

Whereas color vision should be tested with the Farnsworth D-15 test and applicants should not wear ‘color correcting’ lenses during the color test (eyesight standards for police recruitment). A similar wording is used in the eligibility notes of the British Transport Police.

As the last station, we have a look at Switzerland, the country I’m living in. The regulations I found are the most fuzziest ones. The Kantonspolizei Zürich is looking for people with some Farbwahrnehmungsfähigkeit (ability of color perception) and the Kantonspolizei St.Gallen states that aspirants must have in der Praxis ungestörte Farbwahrnehmungsfähigkeit (undisturbed ability of color perception in practice). This is free to interpretation.

Police Officers Job Offers

Looking at some actual job offers for police officers, you will find some similar or even stronger wordings as in the regulations mentioned above. The City of Manteca expects you to be free from significant color blindness and also the City of Pasadena states explicitly, that you have to be free from color blindness. Compared to this the formulation chosen by the City of Ames sounds a bit less restrictive: Vision cannot be inhibited by color blindness or night blindness.

But anyway, job offers seeking a police officer are most often including one of the wordings above and sound very restrictive. Don’t be intimidated by those formulations. Of course everybody is always looking for the perfect match in a job offer. But if color blindness is your only disadvantage you might find your way through anyway.

Your 6 Steps

Recapitulating the facts listed above about regulations and job offers, you have to conclude that color blindness does really matter when you try to apply for an employment as a police officer. With a severe color blindness there is only a little chance to be employed. On the other side with a mild form of color vision deficiency, you might have some chances. Specially in the UK, where the regulations are the most liberal, you could make your way.

Let’s go back to our initial question, if you can become a police officer when suffering some type of color vision deficiency. As we learned, the answer is neither yes nor no. It’s something in between. And becaus you not just give up but keep trying hard to accomplish what you are aiming for, I list six steps you have to take to become a police officer despite your color blindness.

  1. First of all you have to check the severity of your color vision deficiency. This can be done either superficial with some online color blindness tests or thoroughly at your local eye specialist. If you suffer from a strong form like complete red-blindness, it will get quite tough for you to find a job as police officer. So this first step should help you to plumb your chances of success.
  2. After that you should try to find the eligibility notes of your chosen future employer concerning color vision. There are many different nuances in the regulations and they will give you some idea, what they demand. For example the LAPD is much more liberal than some other police departments.
  3. Before you apply you might ask, if color correcting lenses are applicable. There is a possibility of buying some lenses, which can help you to better distinguish certain colors. They don’t make you see more colors, but help to see some differences you can’t see without them. Some police departments might allow you to wear such color correcting lenses. Don’t hesitate to ask them.
  4. If you’ve taken the first hurdle of the employment process, you almost certainly will have to pass a color vision test. Take the test as good as you can without cheating. This will show them the truth about your color vision abilities and of course will be the basis for their decision making. If your application will be denied, try to find out the reason behind it. Maybe it’s not only your color blindness but also some other aspects. And if it is only because you’re colorblind, try to find out more about it; why they won’t employ you. This will help you to get a better understanding, if your type of color blindness is a barrier or not in your job life as a police officer.
  5. Failed the first time? Don’t be disappointed. You might try different police departments where you can apply as an officer. This will take you back to point #2 of this six steps list. And because regulations can be so different, there is most often a chance at another place to get the job you want. Only if you applied for more than one job you can say, that you did everything to make your dream become true.
  6. And if the first five steps didn’t help you to become a police officer, why not start with an other job in the police department and go on from there. There are not only police officers working at a police department. You might find another job you can start with and make your own way. If you are inside the system, usually some more opportunities will open up for you. So don’t hesitate to build your own personal career.

An to answer the starting question: YES, you can become a police officer even if you are suffering some form of color vision deficiency. BUT the way might not be the easiest one and it definitely won’t become true for some of you who are severely colorblind.