Re: Icon love

[Calum Benson <calum benson sun com>]

Carl Nygard wrote:

> He said normally, one light seems brighter, and based on whether it's
> brighter at the top, or the bottom, he knows to stop or go.  I think it
> would be the same with colored icons -- colorblind people would
> differentiate because the brown/grey on top means stop, and the
> brown/grey on the bottom means go. 

Well, that depends which particular shades of green and red you use. 
But you're right, there's one particularly important usability rule that
applies here (<plug>which you'll find in the latest draft of the HIG, of
course</plug>):

- Never depend on colour alone to distinguish two objects.  

In the UK, all traffic lights used to have "STOP" written on the red
light, for example.  (They don't any more, presumably because all
traffic lights in the UK have an identical configuration, and Stop is
always at the top).

There are various websites around that give good advice on what colours
and colour schemes are "safe" to use for colour blind users. In general,
though:

- don't "pair up" colours that are similar in either hue, saturation or
brightness.  

- when colours need to be distinct and recognizably different, select
the light colours from orange, yellow, green or blue-green, and the
darker ones from blue, violet, purple or red. (Most colour blind people
already see blue, violet, purple and red as darker than normal.)

A particularly useful resource is http://www.vischeck.com, which
simulates how images and websites look to people with some types of
colour-blindness, and lets you upload your own-- try it with a
screenshot of your latest GUI and see how it fares!

Cheeri,
Calum.

-- 
CALUM BENSON, Usability Engineer       Sun Microsystems Ireland
mailto:calum benson ireland sun com    Desktop Engineering Group
http://www.sun.ie                      +353 1 819 9771

Any opinions are personal and not necessarily those of Sun Microsystems