Colour blind accessibility test.

**LazyJim** · 10-20-2003, 09:54 AM

I don't know how many of you ever thought about the fact that many colour blind people will be using your sites, or how important you think the subject is.

It's not often that colour is vital in communication, but it is sometimes, for example when the colours you choose for text and background end up looking the same for a colour blind person.

Vischeck will simulate how things look through the eyes of a user with colour deficient vision.
http://www.vischeck.com/
You can use it to test your images and sites.

If you wat more information on colour and how to design for colour blind users, just ask.

DaveyBoy · 10-20-2003, 10:00 AM

you can't really do much about it though, so i can't see myself changing the way i design cos of this.

ATLien · 10-20-2003, 10:08 AM

I have a benefit over most people I am 75% color blind in ome eye so I can sometimes tell how the shades of grey will appear.

**LazyJim** · 10-20-2003, 11:20 AM

lol atlien thats a great "advantage" - guess you're lucky.

DaveyBoy you're right you can't do much about it but there are a few simple solutions. You can ensure that background lightness is as far away from foreground lightness. Then if the page were converted to greyscale you could still read it.

Brian · 10-20-2003, 11:21 AM

Also see:

http://colorfilter.wickline.org/

**LazyJim** · 10-20-2003, 11:23 AM

Many web sites offer alternate style sheets for BIG text, offering a colour-blind friendly one might be good too.

Some poeple consder it more important - I bet the colour blind ones concider it important for a start!

A company logo is often very important so that might be a good place to think about it, depending on the amount the corporate image depends on colour.

**LazyJim** · 10-20-2003, 11:26 AM

Quote:

Originally Posted by Brian

Also see:

http://colorfilter.wickline.org/

cool, and anothe badge that one could add to one's accessible and valid sites!

**fishfreek** · 10-20-2003, 11:28 AM

Hm, interesting.

Im trying this site on internet-marketing-research.net to see if it says the site looks like I see it or not since I have a form of colorblindess.

So many people dont properly understand it and say oh so you cant see color what color is this (pointing to their shirt).

What they dont understand and need to be explained is that the color I see is different from the color they see. We both interpret it as a given color but it might be less vibrant to a color blind person or it might appear as an off shade.

I find myself less sensitive to red's. In fact from a distance during the day I have problems picking up red stoplights. So basicly if Im comming up to a light that I cant see as being green or yellow I assume its red.

Guess you wont truly know what a color looks like to someone else unless you can acutally see thru their eye and brain.

Brian · 10-20-2003, 11:30 AM

For some examples of how color-blinde people see certain websites, I'll post links to IMR.

Protan / Deutan / Tritan

Also see: Mono and Monochrome

**fishfreek** · 10-20-2003, 11:33 AM

http://www.vischeck.com/daltonize/

about 2/3ed down the page. Is the number 45 in all four disks?

Brian · 10-20-2003, 11:35 AM

I can barely see it in #2, took me about 15 seconds to notice.

**fishfreek** · 10-20-2003, 11:48 AM

ok. That just confirms yet again that I am to some degree. I only see it in disk 3 and 4.

I find it interesting to see what these filtes say sites look like to me. of course i see a site one way and thats how I expect it to look. You see it and you expect it to look one way.

When I use the filters of course my color blindness is doing a number on the filtered colors aswell so i guess they are double filtered. Seems like they made the reds more of a green in color and the greens more of a greyish.

Jazzee · 10-20-2003, 11:55 AM

I can't see it in #2.

tigibit · 10-20-2003, 11:58 AM

thats crazy...i can only see it in 1,3, and 4

**LazyJim** · 10-20-2003, 12:20 PM

If u aren't colour blind you aren't supposed to see it in the ones made for colourblind only viewers.
*edit - as far as I know.

We had a brick layer once that was insensative to reds, we were working on a driveway and we said to mix the darker reds and lighter reds more evenly. He said they're all grey!

AcRoNym · 10-20-2003, 03:10 PM

no 2 nah nowt there for me

SN3 · 10-20-2003, 04:16 PM

my site just looks kinda purple

Rick · 10-20-2003, 05:18 PM

I'm wondering how accurate this is. It's doing some pretty screwy things with my CSS.

**fishfreek** · 10-20-2003, 06:41 PM

Well rick i think its almost impossble to tell other than that the changes it does is probably some kind of scientific basis.

Given that its really hard to know what something looks like to you or the next person. Sure you might say "it has a blue background" but what does that mean? whats blue to you might not be blue to them in the respect that if you had a third set of eyes athat could see what both of you was seeing then they could say blue to you is equivlent to navy blue to them and maroon to you is equivlent to a near black color to them.

But given that both people had grown up with their parents and teachers pointing at a color and saying "RED" we learn that what we see is called RED. Reguarless of what we acutally see we learn its RED. Thus what you see when you look a a red card and what I see when i look at the same card we will both call red but the shade or color tone might be totally unique.

Rick · 10-20-2003, 06:46 PM

i understand what you're saying fishfreek- but i dont think color blindness would alter anything more than how colors look. this site is changing my site structurally... so i can't vouch for it's validity.