NetNews Usenet Archive 1992 #26/NN_1992_26.iso/spool/sci/physics/18236

Internet Message Format | 1992-11-06 | 1.8 KB

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From: [e-mail] (Richard M. Mathews)
Newsgroups: sci.physics
Subject: Re: Simple Question on Color
Date: 5 Nov 1992 23:40:14 GMT
Organization: Sunsoft Inc., Los Angeles, CA.
Lines: 25
Message-ID: <[e-mail]>
References: <[e-mail]> <[e-mail]> <[e-mail]>
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Keywords: color, tv, violet
Originator: [e-mail]

[e-mail] (FRED W. BACH) writes:
>     Yes, and speaking of color tv, since my favorite color family is
> the violets, it always bugs me when true violets (not blue+red phony
> attempts at it) are picked up by a color-tv camera.  Now I don't
> know what *every* camera out there does, but some will simply *not*
> pick up this violet and display it.  All you get is a pure bright
> blue.  Is this because the true wavelength of the violet is outside
> (i.e., not between) the spectral responses of the phosphors used?

I would think that you get a pure blue because the camera's red detector
does not have the same small peak in the violet that our eye's red cones
do.  Only the camera's blue detector responds to the violet light, so the
camera produces a blue image.

If the camera's red detector did have a tiny peak of violet sensitivity
then the camera would detect a combination of red and blue.  What would
appear on your screen would be purple.

Without a TV which includes a violet phosphor, there is no way that any
camera can make your TV show violet.

     Richard M. Mathews            F oster
                     E stonian-Latvian-Lithuanian
[e-mail]          I ndependence and
                       F reedom!