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From: kassover@minerva.crd.ge.com (David Kassover)
Newsgroups: comp.graphics,sci.med
Subject: Re: Greyscale to colour.
Message-ID: <9063@crdgw1.crd.ge.com>
Date: 27 Jun 90 19:43:37 GMT
References: <1536@med.Stanford.EDU> <1597@quando.quantum.de> <1613@med.Stanford.EDU> <1990Jun27.192933.18169@sdd.hp.com>
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In article <1990Jun27.192933.18169@sdd.hp.com> andrea@sdd.hp.com (Andrea K. Frankel) writes:
>In article <1613@med.Stanford.EDU> rick@hanauma.stanford.edu (Richard Ottolini) writes:
>>In article <1597@quando.quantum.de> hintz@quando.UUCP (Stefan Hintz) writes:
>>>>However, when I watch a color TV signal in B&W I often have no problem
>>>>identifying the color of objects and I don't know why.
>>>
>>>I know why ...
>>>You know the sky is blue, the trees are green, etc...
>>
>>Most TV scenes are inside buildings.  It is the color of people's clothes,
>>the walls, etc. that I see in B&W.
>
>Is it possible that you are slightly colorblind, Richard?  One of my
>friends who is told me that he sees many things as subtle shades of
>grey.

No doubt *all* of us perceive color somewhat differently from
each other.

The sky isn't blue (at least where I am), except shortly before
sunrise and shortly after sundown.  Most of the rest of the time,
when it's not grey, it's cyan.  (unless you use Fujichrome, in
which case some would have it as blue)

I submit, therefore, that, mathematical transformations aside,
there can be no one, true, grey-to-color mapping.  Find one that
pleases you (or your clients) (and don't hesitate to use
non-linear blending), and let it go at that.

--
David Kassover             "Proper technique helps protect you against
kassover@ra.crd.ge.com	    sharp weapons and dull judges."
kassover@crd.ge.com			F. Collins