Tuesday, October 18, 2011

Mystery of Magenta

Why doesn’t magenta appear in the rainbow or in a spectrum cast by a prism?



(Video Link) This minute-long video explains that magenta (or "pink" as they call it here) is an "extraspectral" color. It's an invented color made to fill the gap between red and blue.

One way to achieve magenta is to overlap the two extreme ends of the spectrum.

 
Magenta is considered a primary color of printing ink, developed in the 1890s. It's the "M" is CMYK. For the purposes of charting the color universe, we regard it as a pure color, but it’s really a composite of red and blue.

Magenta sits directly opposite green on the "Yurmby" color wheel. You can get magenta light by subtracting lime-green light from white light. Magenta is also an afterimage of green. Look at that green dot for 30 seconds and then look at white screen to the right, and you'll see magenta. This is a reminder that color doesn't really have an objective existence apart from our perception of it.

Color theory is full of these niggly exceptions, and that's why it's so challenging to write about. Color theory just doesn't come out neatly like a geometrical theorem.

In the artist's practice, it lives at the intersection of the vagaries of visual perception, the chemistry of pigments, and the physics of optics. I was aware of all this when I wrote Color and Light, but if you include all the qualifications and footnotes, the book would have been 1000 pages instead of 224.  I see the blog as a way to extend the book. And maybe that's something an app edition could do.

Magenta on Wikipedia
Check out the "Rotating Dot Illusion" from Biotele

11 comments:

Anonymous said...

If you angle a compact disc just right you can see magenta in the spectrum.

SE said...

Heh, I thought it never showed up on the spectrum because it's a hue of red.

@etc, etc- I just tried that. Is subtly next to purple.

Anonymous said...

Sam,
It's quite distinct in certain positions. I suppose magenta just requires music and coddling before it feels relaxed enough to express itself. :)

Krystal said...

mhhh... very interesting. Actually, this question of pink and magenta are tricky to me for a long time and I am not quite sure I understand it well.
In the video, they use "magenta" and "pink" as the same concept. But is it really ?

You can actually make a pink from red, but not a magenta, am I wrong ? Quite the opposite, in the pigment system (and not the light system), you can create a kind of red by mixing magenta with a bit of yellow, right ? I wonder if we really shoud consider the two of them the same way...

Jared said...
This comment has been removed by the author.
Jared said...

I meant to say "1,000 page apps weigh (and cost to reproduce/distribute) the same as 224 page apps." (And they can play videos, like gallery flambe.)

James Gurney said...

Krystal, Pink and magenta aren't really the same thing, as pink is really a tint (whiter or paler version) of either red or magenta. But pink is a more familiar color term. I used to call magenta "cool red" before I got used to calling it by its rightful name.

Krystal said...

so, that's it... Thanks for the answer !

Anonymous said...

I've always wondered how light from each end of the spectrum could possibly fade into each other on a color wheel. Now I know. Thanks.

runninghead said...

Great idea! Would love a Gurney App.

Sketching Artist said...

Thanks for the informative post. I received it in my email just in time before my Color & Design class. I was able to print out copies for the rest of my classmates.