Great big amazing - super-stupendous kudos to the people of Adobe for bringing me this opportunity. I and my design work will forever be impacted with this knowledge!

I think the bigger challenge and better alternative for a designer is to create one design that can be easily viewed by everybody. It’s not color in itself that causes trouble, even if it’s a red/green combo, but only when you use those colors as visual cues. So just follow the basic guidelines when you’re designing visual cues and you won’t have to worry about completely separate designs for a subset of your viewers. I highly doubt that using only red/green combos, or other difficult to differentiate colors, are critical to the overall design of any site.

I’d like to use the opportunity to ask something simple. Please don’t get me wrong, I understand and wholeheartedly agree UIs should be usable by everyone but, with a progressive enhancement goal of sorts in mind, how would you feel about a high contrast option in a web-app UI, such as Windows or Mac OS offer? Would that feel as discrimination?

What I mean is: in order to appeal the most to both users blessed with all the rods and cones and ones with special visual needs, the designer could, perhaps, for example, add an option which enhances contrasts and/or adds new layers of differentiation to an interface. Something like a link to a screen-reader version, which quite a few websites and applications sport today.

I certainly believe the least common denominator must be great usability for everyone, but if there’s an option to make the UI better for everyone using additional options, would that be a bad idea, in your opinion?

On the other hand, I also think a great designer should embrace this kind of additional challenge, in order to achieve even better results. So this is more of a general wondering actually.

~Matt

Yes, I have color deficient vision. Yes, a lot of websites I visit are a torment to deal with because of poor color choices.

I also fly airplanes. To get a pilots license (USA) one must pass a medical exam, including a color vision test. I flunk the test (colored spots in an image where a pattern in the spots show a letter or number) every time. The FAA accounts for color deficiency by letting those who flunk the standard color vision test by taking a different exam administered directly by the FAA. The exam allows you to demonstrate your ability to distinguish between “aviation red” and “aviation green”. The FAA has chosen specific shades of red and green that are used in various signaling mechanisms (tower signals, navigation lights, etc) that are distinguishable by most color deficient people. The red looks, well unlike the others. The green looks blue. The white, isn’t blue, isn’t the red thing. It works for me.