According to statistics, around 7.5% of the men and 0.5% of the women are colorblind. But what does that mean? Are nearly 1 out of 10 people unable to see colors? No, not exactly. There are in fact very few people who can only see in black, white and greys. This type of ‘real’ colorblindness is very rare. Red-green deficiencies are by far the most common. Moreover, if we reagard, black, white and grey as colors too, only the fully blind are colorblind. Therefor the term ‘colorblind’ is misleading. It covers a whole range of deviciencies.
This is an image of vegetables, as seen by people with normal vision. Below is the same image, as seen by people with the most common types of ‘colorblindness’: protanopia, deuteranopia and tritanopia.
The vegetables as seen by a person with protanopia (red-green deficiency).
The vegetables as seen by a person with deuteranopia (another form of red-green deficiency).
The vegetables as seen by a person with tritanopia (blue-yellow deficiency).
So how to deal with this from a designer’s perspective? There’s a simple trick to test whether people with a vision deficiency see someting or not. Take a picture and turn it into black and white. Here’s the same fruit in black and white.