Noah explains what it's like working in web design with colour vision deficiency (CVD). Gives a great overview of what CVD covers and why some people can see more/fewer colours than the average person; basically it boils down to whether you have all three (or four!) kinds of cones in your eye and if they have greater/lesser sensitivity, allowing them to understand a wider/narrower range of wavelengths. It can also be caused by brain signal interference and other cognitive phenomena.
This means that those colors in the spectrum effectively “drop out,” but since the light is still there, the brain translates it into a color based on peripheral data picked up by the other cones, combined with its brightness level.
Our cones are split between short, medium, and long wavelengths, but their exact calibration is determined by a lot of nuanced genetic and environmental variables. What's more, other biological variance impacts the light that ever reaches the cones:
The lens and cornea physically block very short wavelengths; it’s why we can’t see ultraviolet light directly, even though we have the sensor capability.
Which is why people who lack lenses (or have them removed as part of cataract surgery or other vision corrections) can see UV to some extent.
When something is only conveyed with color, that’s a gap where information can get lost on a large group of people.
Form factors are important. If colour is a major signal/indicator in a design (e.g. a traffic light) then there should be a secondary signal. That could be iconography or animation or, as with traffic lights, just always being a specific order i.e. form.
Color can enhance the message, but shouldn’t be the messenger.
Trello has a neat feature where colour labels can also have explicit background patterns, like zigzags and dots.
You can Shift + Click any colour in dev tools to cycle through colour formats. Super useful!
It's baffling to me that colourblindness has been something that has been used against Noah to skip him for promotion or reject his progression at work. Sigh. Still, I've definitely been guilty of the hundred-questions approach to finding out someone was colour blind (sorry Sam) so will need to internalise that.
As of February 2020, 86.3% of home pages tested had insufficient contrast. So, what does that mean? It means that the information on those sites is not being conveyed equally, to everyone.
I like that I can bring a singular perspective to the table and a voice for others like me; I am able to offer insights that others don’t necessarily have.