Say Goodbye to Red-Green Color Scales

I used to love them, but it’s over now: diverging red-green color scales.

red green scale

I bet the reason for the popularity of red-green color scales is that they are so easy to interpret (at least in my culture). Green means good, red means bad. For instance, the above map shows the income of private households for European regions. I used a diverging color scale to show the difference from the average income (bright yellow) with higher incomes in green and lower incomes in red. In fact, I picked the exact colors from good old flare visualization toolkit.

But there’s some trouble with this scale. Firstly, as alluded to above, the meaning of red and green vary a lot in different cultures. According to this helpful collection of Color Meanings By Culture, green is negatively associated in some Eastern cultures like China or Indonesia while red is associated to love, happiness and a long life.

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Generating Color Blindness Test Images with Processing

My wife recently observed my two-year-old son eating green strawberries and is now curious if he has some kind of red-green color blindness. Unfortunately, he is not yet able to give us the name of numbers, so the commonly used Ishihara test images won’t do. Well, I thought it´s a nice idea for this rainy Sunday afternoon to generate some of those images myself. Instead of numbers I used simple images of things I knew my son is able to name. If you like, find the source files here. The icons are taken from thenounproject.

My wife recently watched my 2 years old son eating green strawberries and was now curious if he has some kind of red-green color blindness. Unfortunately, he is not yet able to tell us the name of numbers, so the commonly used Ishihara test images won’t work in this case. Well, I thought it would be a nice idea for this rainy Sunday to generate some of those images myself. Instead of numbers I used simple images of things I knew my son is able to name. If you like, find the source files here. Icons taken from thenounproject.

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