"Yokel" wrote in message
...
"DW downunder" noname wrote in message
u...
|
...
|I understand the incidence of colour vision impairment is around 25% of
males
|and a low % of females, maybe 13% of the total population. Likewise, it's
|amazing how many maps are hard to read for this 13%, how many documents
use
|nice red script over a beautiful verdant green tree background - even our
|local RAC has managed that one.
|

Is it as high as that? That means you would expect two or three people in
each cricket team to be affected, but in all the time I have been at
Cadnam
(over 30 years) only one person told me that they had a problem. Trying
to
pick a red cricket ball off a green pitch when both appear to be the same
colour (as I understand it, very few people see in black and white, most
colour-blind people see fewer different colours than the rest of us) must
be
a challenge. I have enough trouble and my colour vision is good (it was
tested when I joined the railway). Perhaps many people either learn how
to
deal with it (a normal red ball is a significantly darker shade than the
pitch, unless the grass has been left very lush) or they take up sports
other than cricket.

But if your figures are correct, then about the same proportion of the
population are affected by each "problem". I have seen somewhere that
left-handedness is also more prevalent in males although nowhere near to
the
extent as colour blindness, which is carried on the "X" chromosome so
women
have got two chances of having the genes for correct colour vision whilst
us
men only have one.

BTW there is DDA guidance on what colour combinations should be used. I
can
remember this from my time as a announcer at Southampton Central, where we
has rules as to what colour combinations we should and should not use on
display screens. Red on green is definitely a no-no and even people with
normal colour vision may struggle with this as the clash of bright colours
confuses the eye.

Unfortunately, because of the amount of information you need to get on a
map, and so the need to colour code some of it, it is much harder to avoid
problems there. But different companies use different colour schemes so
shopping around might find one which works for you.
--
- Yokel -

"Yokel" posts via a spam-trap account which is not read.



You know, the hardest part for me, apart from mistaking boundary lines for
roads, is the use of colour scales for altitude in topographical maps. I
wish there would be a combination of colour and texture to make colour
vision less of a handicap.

DW downunder