Today I was whinging about getting yet another email, nothing odd in getting emails you may think, however for me as a colour blind person, sending me an email that is written in a colour I cannot see properly just ends up as being grey and if the colour is a bright colour it is a light gray on a white background. This is deeply deeply annoying so I tweeted my discomfort and sent a polite but firm email to the sender asking them to send emails to me in a format that I would easily read.
My tweet brought several responses from UI designers keen to understand where I was coming from and asking me for some hints as to how to make their designs better for the colour challenged.
Colour blindness is alas sometimes forgotten and to be fair it is more of a pain in the arse than a real handicap. However it is deeply deeply irritating when you land on some sites or get emails
that the designer or sender at the other end thinks are dead cool but for the colour blind are
at best confusing or at worst just un-usable.
I was almost totally colour blind in my late teens early 20's and I can see a little blue and a little green and no red at all. Why had I not noticed you may ask well we learn colour through association with known "things". The sky is blue, the grass green and milk white, we then learn to associate that colour with other things. For colour blind people they can recognise the colour from the context it is in. Confusion only
arises when confronted with something unkonow and the CB person has to guess by the tonal value what colour it might be.
The eye has two light sensitive cells, Rods and Cones. Rods are mainly clustered around the edge of the visual field and cones in the middle. Rods see tones and Cones see the colour.
Colour sightedness is basically a problem that is usually genetic and usually found on the Y chromosome making it much more common in men.The problem manifests itself with the Cones they are either malformed, don't work or just arent there at all. I was born with only 11% of the Cones I should have so whilst I can
can see some colour I am mostly monchromatic. The up side is that I have more Rods
which are smaller than cones which means I have extremely good visual accuity :-) always
an up side eh?
About 1 in 10 Europeans mainly men have some level of two colour colour blindness, about
1 in 1000 are like me totally or very nearly totally colour blind.
It is worthy remembering that someone that is Blue colour blind does not mean that there is just nothing there at all they can still see something but
just not in way you see it. It will be a gray that matches the tonal value of the actual colour.
I paint and I love painting and I am asked "How can you being colour blind paint in colour?" Well paint manufacturers helpfully put paint in tubes with a lable on it that says "Blue" or "Red" and comes with a Colour Index for example French Ultramarine Blue has PB 29 (77007), so contains Pigment
Blue 29 and is color 77007. Simple when you know how ;-)
Similarly I am often asked .. "How do you know which is the Red Stop light?" well that's easy
it usually has STOP written on it as well as being red and more obviously it is always the
light at the top of a traffic signal ;-) and they are tonally very different.
On the other hand put me infront of the old style electrical cables
(Brown Red and Green) I just cannot cope. Thankfully the new wiring cables are a dark
one, a light one and a stripy one and I have stopped blowing up toasters.
Now I am not saying that you should go deliberately out of your way to make your
UI colour-blind friendly, please make your site as glorious as you can for the 90+%
of visitors that can see all the colours. However keep me and my kindred in the back of
your mind and offer us some help if we need it.
Some things to remember and or do ...
Don't use ONLY color to indicate something specific on your page.
There is nothing quite so fecking annoying as getting an error message that
says "Please correct the entries highlighted in red" when you can't see red.
and because it is a "dark" hue it looks just like black. Use color and a * or > as well to indicate the problem.
Similarly having a RED alert box with White writing does not to a Red colour blind person convey the same "Danger" context as it would to a colour visioned person. Add a nice Icon to help with the context.
Desaturate your images to see if they still have impact to grey scale.
is NOT how most color blind people see the images and will need to be tweaked slightly giving less contrast (make it lighter) as the viewer may not see the tones in the same way you do... but it will give you a
quick and easy way to tell if the image is still useful particularly if you have text or navigation objects on top of the image.
Try to avoid placing red and green together. (RG colour blindness is the most common)
Especially on items like navigation buttons, the text can actually blend into the
background, making it very hard to read.. here (CTRL+A is your friend if you are colour blind)
Try and avoid using two colours that are of similar tonal value - and this is not as easy as it sounds for example this to color sighted people is fine and easy to discern. The outer colour is RGB(112,161,207) the inner colour is RGB(97,179,122)
Gray Scale this image and you get the idea of how this looks like to me
It is always better to have a dark colour on a light background, you can reverse this but it isn't quite so good.
Also be aware that it is more difficult for everyone to distinguish
dark (low value) and/or saturated colors
(e.g., a 16-color palette blue or red against black),
and extremely light pastels,
particularly in low or bright light conditions.
This is doubly true for the colorblind.
If you can, find a color blind friend or relative to look at your site.
If you're not color blind it's often very difficult to tell what they
might have trouble with. The challenge is as can be seen above that if they can't see
something, they might not even know they aren't seeing it.
http://colorfilter.wickline.org/ is a useful place to go to test web pages
it isn't brilliant.. but it does show you what the various types of CB people
may see when they visit your site. Try your favourite business sites and you will be surprised how different they look to the colour blind.
Who can say where the road goes, where the day goes? Only time....
Tue, Jan 29th 2013 11:41a Steve McDonagh Although I am not over in Orlando at Connect 13 this year the distance from my friends is all the more difficult with the news that one of the "Geek Bikers" , Kenneth Kjarbye from Denmark, had an fatal accident on the Annual Hog ride.
Stuck in Ireland I have only my words to reach out to Kenneth's family and my friends who are at this time in a dark place they were not expecting to be not even in their worst nightmares .. but there are no words I can think of that really do help, there ar [read] Keywords: community
Offical start of the Domino Charity Marathon Dander For Cash 2013
Wed, Jan 2nd 2013 5:28p Steve McDonagh The Dander Route
A while back I mentioned that there would be a reprise of the Domino Dander for Cash this coming year. It takes me great pleasure to announce that this year's Dander will be longer bigger and more challenging than the two that have preceeded it. As of today it is offical, a spreadsheet has been created and accomodation is being looked at and foot care product sales have gone through the roof in certain places around the UK and USA
When I say "we" these are the brave [read] Keywords: domino
Interesting thing coming in ECMAScript 6
I try were possible to keep up to speed with what's about to come along and it was with this in mind I I was casting my eye over Juriy Zaytsev's EMCAScript 6 compatibility chart and I started to notice green's appear. Some of the current or beta versions of the browsers are [read] Keywords: ibm
The new CSS3 @supports() rule is really rather cool!
Fri, Nov 23rd 2012 5:42a Steve McDonagh As all devs know , browsers can in varying degrees be a right royal pain in the arse when it comes to standards compliance and when you throw in companies like Never Upgrade a PC Till It Breaks Inc. who are still running XP with IE6, planning your super duper new web site to support them can be fraught with problems.
Most of us are used to the idea of designing a UI that degrades into a DBA-UX (Different But Acceptable User Experience) to do this we have to be able to work out exactly the su [read] Keywords: blogger
Useful i5/OS tip - Displaying Locks on an IFS Object
Thu, Nov 22nd 2012 6:59a Steve McDonagh I was plagued this week by an odd problem on one of our i5 boxes. I was trying to use the CPYFRMIMPF & CPYTOIMPF to pull in data from a new Japanese division that uses nothing but Japanese characters in their data. This of course means UTF-8 / Unicode data, which can be a bit of a pain to set up in a DB2/i5 data table (particularly if someone forgets to make fields something other than CCSID 65535!) Anyway.... I could get data off the system using the CPYTOIMPF into the IFS no problem at a [read] Keywords: blogger
Domino Dander for Dosh 2013
Thu, Nov 15th 2012 11:31a Steve McDonagh Gentle readers some non-techie news!
The bold Eileen Fitzgerald and myself are planning a Dander For Dosh in May next year.
Eileen and were joined by the indefatigable Carl Tyler for 2012's walk along the coast between Bray and Wicklow in Ireland. We didn't pester the life out of you because we didn't get the giving organized in time for the actual walk. This year we will get our act in gear and start demanding money with menaces in January - You have been warned!
Conscious of the f [read] Keywords: domino
Principles of Design #6 - Colour Theory, The basics
Mon, Oct 15th 2012 4:32p Steve McDonagh Right I could wax long an lyrical about colours and how to use them, which I have to say probably sounds odd coming from me given that I am nearly colour blind. However I have been colour blind all my life and to me the sky is blue and grass green because that is what we are taught from when we are small.
Colour is very hard to describe to someone else without using the word "like" in fact most colour names are based around a descriptor that carries with it the meaning of the colour being [read] Keywords: blogger