Color vision deficiency
Very powerful video and message raising awareness about this deficiency and trying to bring #ColorForAll:
An excellent article describing the types of Color-blindness:
The most common broad category of color-blindness is often called red-green color-blindness, but this does not mean that these people cannot see reds or greens. They simply have a harder time differentiating between them.
This is the most common and entails a reduced sensitivity to green light.
This is a reduced sensitivity to red light.
This is a reduced sensitivity to blue light (not very common).
People with this condition cannot see color at all (not very common).
This test from EnChroma shows that I have medium Protan color vision deficiency. This means that I have reduced sensitivity to red light. About 2% of men experience this type of color vision deficiency.
The good news is that the glasses sold by EnChroma presumably improve this condition. The bad news is that they come with a quite high price tag.
To experience how a person with color vision deficiency sees the world, check this app: Colorblind Vision.
Here you can find a classic color blindness test – composed of 24 Ishihara images.