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Re: LA Rail Revival
M.B. and C.M.McDonald wrote in message <7ka9ds$3o4tk$1@titan.xtra.co.nz>...
>
>The human eye also has a part to play in making colour mixing work, but I
>don't have any detailed knowledge of the performance of the colour
>receptors in the eye (they're only in the central portion of the eye and
>don't work if the light level is low).
Cones (colour detectors) can be found in every part of the retina, although
they are more concentrated in the central portion, and as you say they only
work in reasonably bright light. Rods (brightness detectors) can be found
everywhere in the retina except the central portion, and they can work in
light which is bright or dim. This has two effects on vision when the light
is dim: everything goes grey, and you can see things better by not looking
straight at them because the centre of your vision is blind.
--
John Rowland - Spamtrapped
Maps of tube stations at http://www.geocities.com/Athens/Acropolis/7069
"If I'd known how Van Outen was going to turn out,
I would have carried on drink driving"