
Color names and their wave lengths and frequencies - ArashPartow
http://partow.net/miscellaneous/colours.html
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schoen
I'm a little confused about the approach to the frequencies here. Most light
that we see (apart from laser light or the result of separating or filtering
light with optical equipment) is not pure monochromatic light at a single
frequency. This is clearly true for many colors in this chart which are given
as combinations of additive primary colors. So, it is misleading to say that
these colors have a single frequency or wavelength. Is the frequency given in
the chart just the pure color that would be closest to the indicated color in
some color space metric?

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ArashPartow
@schoen You do make some very good points, the wave lengths in this list are
based on the assumption of pure colour forms using Dan Bruton's Spectra
approximation.
[http://www.physics.sfasu.edu/astro/color.html](http://www.physics.sfasu.edu/astro/color.html)

Furthermore as you can see in the list composite colours such as white, gray
and black have undefined values.

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hilbert42
"<...> pure colour forms using Dan Bruton's Spectra approximation<...>"

Approximation or not, you cannot assign a unique wavelength or frequency to
perceptual (extra-spectral) colors if for no other reason than that the given
λ(f) is factually incorrect. Moreover, even an approximation doesn't make much
sense, as simply human vision perceives magenta as a very different color to
say various shades of pink (white + red) or any other color near red [orange.
orange-red, etc.]. Basically, there is no single λ(f) - spectral - color that
looks even vaguely like magenta (similarly for cyan, 'fuchsia' etc.).

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hilbert42
This chart is misleading in that it intersperses both true spectral colors
(red, yellow, blue etc. that actually possess unique wavelengths) with extra-
spectral colors such as magenta, cyan, etc. which, per se, DO NOT have unique
wavelengths/frequencies—but which this diagram incorrectly assigns to them.

Non-spectral/extra-spectral colors (magenta etc.) do not exist as true colors
on the visible spectrum as such, rather they are 'perceptual' in that they are
created in our minds by mixtures of other colors (e.g.: magenta being a
mixture of red+blue).

Why extra-spectral colors exist is a rather complex matter and stems from the
very specific way we humans perceive colour (Young-Helmholtz tri-color
perception theory
[https://en.wikipedia.org/wiki/Young%E2%80%93Helmholtz_theory](https://en.wikipedia.org/wiki/Young%E2%80%93Helmholtz_theory))

A better understanding of how extra-spectral colors fit into the overall color
schema and the way we perceive color can be gained from the 'CIE 1931 color
space' (Chromaticity diagram).

[https://en.wikipedia.org/wiki/CIE_1931_color_space](https://en.wikipedia.org/wiki/CIE_1931_color_space).

