Path: utzoo!utgpu!news-server.csri.toronto.edu!neat.cs.toronto.edu!mgreen
Newsgroups: comp.graphics
From: mgreen@cs.toronto.edu (Marc Green)
Subject: re: Psycho Graphics
Message-ID: <91Feb20.131305est.6899@neat.cs.toronto.edu>
Organization: Department of Computer Science, University of Toronto
Date: 20 Feb 91 18:13:24 GMT
Lines: 37

>From: euaneg@eua.ericsson.se (Nils-Erik.Gustafsson)

>>Eugene N. Miya writes:
>>
>>  We are developing sophisticated color graphics systems for scientific
>>  visualization.  For better or worst, most of the scientific community is
>>  male, and 1/6 males have some degree of color blindness.

>Not to be nit-picking, but it's not quite as bad as 1/6 (17%).
>The literature seems to agree upon 6-8% (almost all having a
>green/red-deficiency).
>
>Nils-Erik (Gustafsson)
>ELLEMTEL Telecom Systems Lab

It's not that simple. It depends on whether you are talking about the
truly "color blind" (dichromats and monochromats, who are missing a
pigment or two) or merely color anomalous (trichromats who have all
three pigments but with reduced amount or shifts in spectral
sensitivity). The 6-8% number includes the anomalous trichromats, I
believe. So the real number of color blind people is really quite
small. To make life more complicated, color-blinds fall into two
groups (and a rare third group).

However, it is also a mistake to think that females are never color
blind. The last I looked, there was a lot of research saying that
females who carry the gene for color blindness often have mixed
patches of normal and abnormal retina. They may pass crude color
screenings (like Ishihara) but still do not have normal color vision.

In short, attempts to take color blindness into account when creating
visual displays is probably hopeless. There are too few people and
they fall into too many different groups, each of which would require
different modifications.

Marc Green
Trent University