Project Management by Red and Green Light

When I was working as a software engineer we usually held a status report meeting once a week. As the project leaders wanted to know if everything goes well or not we used simple red light/green light reports. Every team member listed on a simple sheet the ongoing tasks and used coloring to show the actual status:

  • Green means everything is on track,
  • Yellow shows us that there are some minor problems and
  • Red let the alarm clocks ring.

If I would have been the project leader I could always sleep without any concerns. As being an optimist for me everything looked either green or at most yellow, but never ever red. In my eyes only a pessimist could spot the red tasks.

Here my two simple advices for project leaders who base there status reports an red lights/green lights:

  • Use bright yellow, medium green and dark red.
  • In addition name the status/the color.

As there are 8% of men suffering some kind of color blindness this could easily affect one of your team members. Think about it.

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


If you have to color a map and are not sure which color palette you should use maybe ColorBrewer comes to your help. This little online tool shows how a color scheme looks in a map and helps you deciding on the right colors which accomplish your needs.

There is a sample map shown and you are guided through three simple steps for coloring the map:

  • Step 1: Select the count of needed color classes.
  • Step 2: Choose the legend type, either sequential for ordered data from low to high, or diverging which emphasis mid-range critical values or as a last option qualitative with no direct relation between the different color classes.
  • Step 3: After Step 2 different color sets are shown. Choose one and the sample map is getting colored with the appropriate color legend.

The interesting part starts after those 3 steps. If a color scheme is chosen the CMYK, RGB, HEX, LAB or ArcView 3.x (GIS format) values can be accessed. That’s great. On top of that additional information is shown if the chosen scheme is suitable for photocopying, LCD projector, laptop screen, CRT screen, color printing or if it will not confuse people suffering from red-green color blindness.

I tried it out and browsed through many color schemes. Most often it showed that the chosen scheme is ok for colorblind people. But when I had a close look at the colors I could definitely tell that I will have some problems with this color scheme. I don’t know where from they got the information if one scheme is confusing and others are not, but they definitely should have taken a bigger test bed or better algorithms.

Maybe they belief that if red and green are not mixed into one color scheme it is not a problem regarding red-green color blindness. This is a misbelief. The tool is ok and can maybe help you out on chosing the right colors. But please don’t trust them regarding the suggestions about color blindness. They are wrong and give a faulty feeling of certainty.

Related articles:
Choosing the Right Colors
Simulating Colorblind Vision
How the World is seen through Colorblind Eyes

5 Misbeliefs about Color Blindness

Even though there are many people, specially men, suffering from some kind of color blindness, there are many misbeliefs around and some of them deeply settled inside the brains. Let us do some cleaning up and get those straight.

I have chosen five common misbeliefs about color blindness and try to shape them towards meaningful knowledge.

Colorblind people…

  1. see only grayscale and can’t see any colors at all. As the wordings color blindness and colorblind have a liberal usage, this is not true. Most of the people called colorblind suffer from red-green color blindness and some of blue-yellow color blindness. Only very few are affected by achromatopsia and just some of those are completely colorblind. But if so there is a smooth transition to blindness and there is no hard line between really being colorblind, highly sensitiveness on bright light and blindness. And the conclusion is, colorblind people can see colors but just can’t distinguish all of them.
  2. are a risk on road traffic because they can’t distinguish between the red and the green traffic light. No, they can distinguish due to the two following facts. First of all the red light is much much darker than the green light. Maybe colorblind people have to learn the color names on the traffic lights but not the meanings of them. And secondly they are always ordered the same way. Red on the leftside or on top and green on the rightside or at the bottom. Or is it the other way around?
  3. inherit color blindness from their fathers. Well, my father is colorblind too but I inherited it from my mother. The most common red-green color blindness is a sex-linked trait. Therefore it is encoded on the X-chromosome which is passed on from a mother to her son and not the father. In the article The Biology behind Red-Green Color Blindness I go a bit futher into detail on this topic.
  4. have all the same color vision. As contradiction I list the different varieties of color blindness: Protanomaly, Protanopia, Deuteranomaly and Deuteranopia are different sorts of red-green color blindness. Tritanomaly and Tritanopia are more commonly referred to as blue-yellow color blindness. To round up we have rod monochromacy and Achromatopsia. And to top this list they can be more or less pronounced and appear even in different mixtures.
  5. are dumb. Well I have just written this article and I hope this tells you opposite. Of course we can’t name all the colors. But it’s just names and it doesn’t affect the rest of the brain mass – hopefully.

I hope these explanations can wipe out the misbliefs and broaden the knowledge about color blindness.

Further readings:
Wikipedia on Color Blindness
Wikipedia on Achromatopsia

Related articles:
The Biology behind Red-Green Color Blindness
Colorblind People are Wise Persons
What the Doctor says

Firefox Extension – Colorful Tabs

At this very moment I stumbled accross the Firefox extension Colorful Tabs. After installing it you get your tabs showed in very nice colors. I was eager to know if I can distinguish the chosen tab colors as well or if I can’t, so it was installed immediately. After restarting Firefox it looked like the picture shown below.

Firefox Extension Colorful Tabs

Firefox Extension Colorful Tabs in Action

Very nice. And I can even see the different colors. On the first sight it looks good but on the second I start realizing that I can’t find the active tab that easily anymore. All the colors distract my eyes and confuse me. The border which is shown and the bold text on the active tab are not enough for me.

Do I get distracted because of my color blindness or do you have the same problem?

A Colorblind Decides on Colors

I am redesigning my blog. This of course involves some decisions about colors. Ohhh, how I hate it. I mean, in my eyes the chosen colors look great, fit together and don’t jump into your eyes and disturb the overall impression of the page. But if I show my color ideas to somebody not colorblind they often put a smile on their face.

This is maybe hard to imagine how it feels for somebody not struggling with color blindness. But for me it is not funny at all. I try to give my best, use tools who support your decisions of colors and try to stick just to a handful of colors. Still, there has to be always somebody around who judges my creations so I can make the adjustments for the ones without color vision deficiency.

There are only tools around which show you how a page or a picture look like if you are colorblind. But none of them works the other way around. How would it be great to have a tool which tells you its feelings when parsing your newly designed page. And only if the tools mood says “I’m feeling great” you would be sure that your chosen colors fit the eyes of the not colorblind population of our world.

Related articles:
Choosing the Right Colors

RGB is not Hue-Saturation-Value

In a recent article I had a closer look at eyePilot. In my tests two bugs showed up which I reported to the producers of eyePilot.

The more severe bug where they show some wrong RGB values is based on some simple circumstances. This doesn’t excuse the factor that the bug crept into released software. But read yourself the answer from Dennis Purcell, Senior Scientist at Tenebraex Corporation:

Dear Mr Flueck,

You are absolutely right — the rgb values are not correct. In fact, they are the hue-saturation-value numbers that we used for developing the color assignments. At one time they were part of the readout, until we figured that most people would be satisfied with rgb — the right rgb, that is! And it certainly was careless not to have checked those numbers before release. […]

thanks and best wishes,

Dennis Purcell
Senior Scientist
Tenebraex Corporation

So dear programmers living out there. Please test your software, test it twice and let it be tested by others before release date. We don’t want to be beta-testers. That is something we already know from the products released by a company called Microsoft…

Further reading:
New Software Tackles Colorblind Challenges

Related articles:
Battle Agains Color Blindness With EyePilot
Microsoft knows about Color Blindness

Colorblind People are Wise Persons

Albert Schweitzer (January 14th 1875 – September 4th 1965) was a theologian, musician, philosopher, and physician. He received the 1952 Nobel Peace Prize.

An optimist is a person who sees a green light everywhere. The pessimist sees only the red light. But the truly wise person is colorblind.

This quote was coined by Albert Schweitzer. I don’t want to start a philosophic discussion here but would like to have a closer look at the last sentence But the truly wise person is colorblind from a logical point of view. In short this means that all colorblind people are wise. Or doesn’t it? From my point of view where color blindness sits in my neck every second this would be very charming.

Let’s get mathematics out of the bag. The quote says out of being a truly wise person follows that this person is colorblind. Can we also saddle the horse from the back and say if somebody is colorblind he therefore must be a wise person? Unfortunately not. This becomes clear if we look at a little example:

If it rains the street is wet. Can we follow that if the street is wet that it has to rain? No, we can’t. Because there could also be somebody washing his car out on the street or a broken water pipeline fludding the street. But we can look at this situation even from a different angle: If the street is not wet there is no way that it is raining. This helps as a lot to understand the above quote a bit more in detail.

If you are colorblind it doesn’t follow after Albert Schweitzer that you are a wise person. But only if you are colorblind you have the possibility to be a wise person and therefore only colorblind people can be wise persons. I am happy to be one of them as I just showed you :-)

Further reading:
Wikipedia – necessary and sufficient conditions in logic
Albert Schweitzer

Related articles:
Mars in the Eyes of Colorblind Astronomer Schiaparellli

Oliver Sacks about Losing Color Vision

Murli of d’zynovation pointed out in a recent comment the book The Man Who Mistook His Wife For A Hat: And Other Clinical Tales by Oliver Sacks. As being a neurologist he writes books as some kind of science novells. This particular book describes some clinical tales whereof one is about an architect and artist who loses his ability of color vision through a knock on his head.

As this description sounds very interesting to me and because I didn’t buy a book for quite a long time I just surfed over to Amazon and ordered the book. I’m looking forward to find out more about our protagonist exploring color blindness. I will post my impressions in a future article.

Perfect Pitch And Color Blindness

Gareth writes about the Perfect Pitch and tells a very nice analogy between a perfect pitch and color blindness:

There is a very good analogy to perfect pitch – that it is like seeing in colour instead of being colourblind – but it is still just an analogy. When you look at a picture and see a colour such as pink, can you tell me how you know it is pink and not, say, bright orange? No, you can’t. You just know. Similarly, I hear G and I hear that it has all the qualities of G-ness. That’s all. It doesn’t cause bright purple spots to float around that tell me it is a G.

I like this analogy very much. But head over and read the whole article at Dusk Puppy.

Further Reading:
Gareths article about Perfect Pitch
Wikipedia: Perfect Pitch

Battle Against Color Blindness With EyePilot

Almost two weeks ago the news New Software Tackles Colorblind Challenges announced the launch of eyePilot. This little helper is introduced by Tenebraex, a company primarily specialized on tools based on optical technologies.

You can get a 30 days trial to see how it operates and that’s what I did. As a first impression I see a nice little tool with no extras which you anyway never get to use. A very slim interface just showing what you need: a dropdown where you can choose one of four different functionalities (Gray, Flash, Name, Hue) and a few buttons according to the chosen functionality. That is it, very nice. Let’s try one by one.

Gray. Through this option you can color everything gray inside the eyePilot window, except the color you clicked on. There is the possibility to widen or narrow the color range according to your needs. As well you can choose if it should be a light-, mid- or dark-gray. The option Gray is a great helper if you have to find same colors which are spread over a picture or diagram. If there are many colors involved this task is almost impossible to complete for somebody who is colorblind. At How the World is seen trough Colorblind Eyes I already tried to show the difficulties for somebody who is suffering from color blindness with this rather beautiful colored map of the earth.

Name. With the funcionality Name the colors you pick get labeled. I described in The Color of Crayons how it is not always easy to pick the correct crayon if you are suffering from color blindness. As the example picture shows, the chosen crayon is red. I definitely would have said this is brown. Would be great if I could use this tool not only on a computer but also in everyday life.

Flash. This is the opposite of Gray. As long as you click and hold the color underneath the cursor is painted black on the whole picture. A very helpful tool on diagrams including a legend: just click on the color showed in the legend and it is highlighted inside the whole diagram.

Hue. This is the last option and helps you find the best contrasts in a picture. I found a great little example on the web. In the shown photography of the Orion Nebula you can see on the lower part the original and on the upper part the modified picture. Without Hue I couldn’t tell if there exists a nebula at all. Only when circulating through the different hues I can spot it.

As a conclusion I would say this is a neat little tool and can be of great help for people suffering from any kind of color blindness and even people with normal vision. Complex diagrams are even for those (out there) not always easy to read.

While testing I found two bugs which makes eyePilot look kind of unprofessional. If you’ve chosen the option Name and want to change again, the tooltip text and the dropdown box compete against each other. It works but it is a bit nasty.

The second bug is much more severe. If the name of a color is shown the RGB values are written into the tooltiptext as well. You can see it at the example picture above. But the values are wrong. Not only that they are in an incorrect order but also the values are completely wrong. I tested it against photoshop with different colors. This bug really irritates and makes me feel that this tool was definitely not enough tested before release date – too bad.

Further readings:
New Software Tackles Colorblind Challenges

Related articles:
How the World is seen trough Colorblind Eyes
The Color of Crayons