sami: (your argument is invalid)
Sami ([personal profile] sami) wrote in [community profile] accessibility_fail2009-06-19 12:55 am

The devil's in the details

This is quite a minor incident in and of itself, but it's symptomatic of the wider problem.

Earlier this evening I was settling down to watch a DVD with my brother-out-law, Chas. Chas was operating the remotes, and was trying to get the DVD player turned on (shooting past an obstruction, you understand), when I heard him mutter that he wasn't even sure if the screen was on.

Looking over, I saw the red light on the corner of the (LCD) TV was showing, so I said it wasn't on. He switched remotes, hit the button again, the red light turned green and the screen started warming up.

"Okay, now it's on," I said. "You can tell by whether the light in the corner is red or green."

"Wait," Chas said. "They use red and green to indicate? Those bastards!"

Despite long and close association, it took me a second to work it out - he was having a problem because he has moderate red-green colour-blindness. Really quite moderate, but he could still only sort-of tell the difference after I'd pointed it out - he hadn't been aware, really, that the light changed colour at all.

Red-green colour-blindness is relatively prevalent in the male population; in cases like this it's trivial, but the sad thing is, marking distinctions by red vs green is not at all unusual. (Fairly recently, for example, Chas was looking at diagrams of something, and had to get my help, because the diagrams coded different areas by use of red and green dots, and he had trouble telling which was which.)

It's a thoroughly invisible disability, ranging from vague annoyance to occasional danger, but it shouldn't be a disability at all. Red/green should never, ever be used to convey information merely by colour differentials.

[personal profile] treeowl 2009-07-18 12:07 am (UTC)(link)
Be sure to watch your RGBs... If the main distinction between two colors is in RG, you have a likely issue. Of course, there are other sorts of color-blindness too. On the other hand, there's a bit of technology fail: CSS is well enough designed to allow users to absolutely override website text colors, but it does not provide any conditional overrides (e.g., if the colors are too close according to my personal formula, modify thus). There may be more sophisticated techniques available to more sophisticated users, but I'm not sure.
watersword: Keira Knightley, in Pride and Prejudice (2007), turning her head away from the viewer, the word "elizabeth" written near (Default)

[personal profile] watersword 2009-07-18 05:48 pm (UTC)(link)
Thanks! I was doing it visually, and since I'm not R/G clorblind, it was a little nervewracking. Current solution: use only one of them in the whole design, which is not as hard as you'd think; most of my current projects are pretty monochromatic. *revises notes to self*