10/15/96
lue-green instead. This may sound odd for many people, but this is not a
matter of custom. This is a matter of the consideration for the handicapped
minority.
About 10% of white males are colour blind. Most of these people cannot
distinguish yellow and green, because their photorecepter for red light is
defect. (Remember that yellow is the addition of green and red.) All these
double-labelling pictures you frequently see in papers, slides and posters
convey no information to these people. For them, these figures are as
useless as monochrome Xerox copies.
I heard Asian and black populations have slightly lower percentage of
people with such color-blindness, but they do exist. (e.g. I am Asian and I
am colour blind.) Quite a lot of prominent scientists are actually colour
blind.
Although there are also people who have defects in either red or green
photorecepters; they percentage is much much lower.
or people with defect red photorecepter, detecting the differences between
green and green+red, or between blue and blue+red, is almost impossible.
This is the reason why I call for the blue-green combination, which
utilizes no red light. Of course, as suggested in the above posting,
howing two black-and-white pictures side by side is also good, though it
is a bit space consuming.
Previously, there was no way to avoid the red-green combination: Rhodamin
is red and FITC is green; that's it. But now that you can choose any colour
combinations with just a mouse-click on the computer screen, there is no
logical reason to stick to this convention.
Please think about the handicapped 10 % of your audience, and go away from
the awkward convention.
I sincerely looking forward to your understanding and cooperation. Thank
you very much.
ITO Kei
color blind is in fact an ADVANTAGE when veiwing red-green stereo anaglyph
images.
The color is important ONLY as a way of having one or the other image PASS
the FILTER in front of the respective eyes. It is NOT important that one
then be able to distinguish the color of each image. In fact, normally
sighted people often suffer from "color-bombardment" when viewing alaglyph
because their brain revolts at seeing the "same object" as being different
colors with each eye. A red-green color-blind person sees both colors as
grey and therefore is not bothered by this effect.
To repeat: being red-green color-blind had NO effect on the ability to see
red-green anaglyph stereo images (UNLESS the observer is for some reason
totally insensitive to either red or green light rather than merely being
unable to distinguish one fron the other.)
Jim Pawley
Prof. James B. Pawley, Ph. 608-263-3147
Room 1235, Engineering Research Building, FAX 608-265-5315
1500 Engineering Dr., Madison, WI, 53706
JBPAWLEY@FACSTAFF.WISC.EDU
dual labelling, in which case both labels appear the same!
Actually red-green colour-blind people do sometimes have difficulties
with red-green anaglyphs since although the colours appear similar the
intensities are rather different - the red image typically looks rather
darker than the green.
Dr. Guy Cox,
E.M. Unit, F09
Univ of Sydney
NSW 2006,
Australia
Phone:
+61 2 9351 3176|