[comp.cog-eng] What it is like to be red-green color blind

bp@pixar.UUCP (Bruce Perens) (03/06/90)

Since we've been having an academic discussion of red-green color
blindness, I thought I'd fill you in on what it is like to have.

People told me I was color-blind when I was quite young, apparently
because I identified colors incorrectly. Of course it is hard for me to
understand what anybody else sees without being in their heads. I have
no problem driving, and can distinguish traffic lights easily, though
green traffic lights have always looked almost white to me.

I can't distinguish those red-green LEDs. They are used on ATT
telephone instruments (and doubtless other brands). I can tell when
they are flashing red-green because of a positional difference. I have
a serial-line breakout box that uses bi-color LEDs that are very hard
for me to differentiate. For a while I didn't know they were bi-color,
I thought they only went on and off.  There's one of those LEDs in an
SGI or MIPS CPU board that I know is flashing red-green because one
color looks more "fuzzy" than the other (perhaps one wavelength is
blurred more in my eye?).  I have a problem reading resistors, but I
can usually figure them out, and can always check with an ohmmeter. I
can't sort that 25-pair telephone cable - when I last tried it I got
several pairs wrong. I don't have a problem with the telephone quad
cable, the red and green look different, and there aren't too many
choices.  I gave up a job as a photo technician because I wasn't
confident I could judge the quality of my output. I could have used a
colorimeter if it was important, but being a systems programmer was
more fun and paid better anyway.  Yes, I see colors in color TV. Almost
the same ones I see in real life (having checked this with
well-calibrated cameras and monitors in a TV production studio). I
don't pick colors for computer graphics - but we always leave that up
to an artist, anyway.

I get annoyed when people color-code things and do not provide an
alternate coding for color-blind people. The first time I had to use
the D.C. subway, I asked someone "excuse me, I'm color-blind, is that
the red train?". It's easy enough to spell out R-E-D on the side of the
train, though it might look silly to everyone else. I'd at least know
what you were talking about.  People are always helpful in identifying
colors if you tell them you are color blind. It's a good way to get a
sales person to pay attention to you in a department store. Once I
bought a light pink dress shirt, thinking it was white. My favorite
color is red. Sometimes orange-red. Sometimes orange. I can tell a dark
red from orange, but have trouble with shades in-between. I think my
favorite color used to be blue, which makes more sense. I can reliably
identify blue.

About another kind of blindness - I notice some things about people who
are really blind, not just color-blind, and the problems they have
getting around in public. They HATE the
live-music-in-the-subway-stations programs that most cities have now. A
blind person needs to be able to hear where the walls are (yes,
Virginia, you can hear a wall), and amplified music drowns that out.  I
saw a blind person having one heck of a time orienting herself because
of a steel drums concert in the Boston subway.  Box radios don't help
either, but at least it's illegal to play them in the subway. Blind
people are annoyed when you say hello to the seeing-eye dog before you
say hello to the blind person. Sometimes people on the street try to
play with the dog and don't say anything at ALL to the blind person!
And it's REALLY impolite to walk into a room where a blind person is
without saying something. Mumble any kind of nonsense, but give the
poor guy some means of identifying you other than your body odor.

					Bruce Perens
					ucbvax!pixar!bp