Saturday, March 23, 2013

THE BEST COLOR THEORY


In 1704, the great Isaac Newton wrote the first scientific treatise on color theory (the physics of color interaction).  Newton's color wheel began the transformation of color from the unsupported intuitions of artists to the science that it has become today.

Goethe's color wheel from 1810

Chevreul's color wheel from 1855

Today we recognize that our sensory impressions of ideal colors were unreliable.  Instead, we measure vibrational frequencies and map spectrum space, defining quality in quantitative terms.   The science of colorimetry and organizations such as the International Commission on Illumination to help us achieve the miracles that digital color accomplish today.

As Galileo said, "The book of nature is written in the language of mathematics."

Many great scientists have made valuable contributions to this growing body of knowledge.  But the most important and useful color theorist remains Elizabeth Barret Browning:
"Yes," I answered you last night;
"No," this morning, sir, I say.
Colors seen by candlelight
Will not look the same by day.




30 comments:

अर्जुन said...

Elizabeth Barret Browning:

"Yes," I answered you last night;
"No," this morning, sir, I say.
Colors seen by candlelight
Will not look the same by day.

~ That's my lady!

Matthew Harwood said...

Coming back to color after working in black and white is like tasting sugar with your eyes.

Anonymous said...

Forget rgb or ryb. The real test is whether it will get her in the sack.

David Apatoff said...

अर्जुन-- was Elizabeth Barrett Browning the source of your blog name? Very interesting. But why would you assume that the daytime colors are the true ones? It seems to me that candle light has an equally legitimate claim.

Matthew Harwood-- I have to admit that at heart, I am a "drawing" kind of guy.

Anonymous-- I'd put it a little differently, but yes-- Browning's poem does suggest the best test of color: it's not whether the artist's colors are warm vs. cold, or additive vs. subtractive, but whether they can move the other person to "yes."

kev ferrara said...

Objects have no true colors. Colors are sensations of the mind. They don't have material existence. And you cannot calibrate one human's perceptions of color to another, except relatively.

I have to admit that at heart, I am a "drawing" kind of guy.

Yes, that does seem to be your line, watery for Fawcett as you are.

The most interesting thing about drawing to me is that it is what is not drawn that shows the measure of the artist. An eraser is as useful as a pencil. And blank paper is the more farsighted form of erasing. Thus, although drawing comes from the idea of leaving a mark by dragging, in the artmaking event it actually means decision-making.. Which, I guess, only serves to underscore that drawing is inseparable from design which is inseparable from conception.

David Apatoff said...

Kev Ferrara-- the bookend to my quote from Galileo on the importance of math is this sadder-but-wiser quote from Bertrand Russell after 400 more years of scientific results:"Physics is mathematical not because we know so much about the physical world but because we know so little: it is only its mathematical properties that we can discover."

From that perspective, or from the perspective of Descartes, it may be easy to conclude that colors have no objective reality. However, they are certainly phenomena that can be calibrated just as well as any other aspect of reality. It's just that I am most interested in the persuasive effect described by Browning.

As for drawing, yes!

I love that line about the more farsighted form of erasing.

kev ferrara said...

Bertrand Russell is fascinating and maddening in equal measure... that quote sounds humble. Yet by implication it denies that human experience is a method of discovery. Which is to say, it stands against the idea that perception, qualitative reasoning and narratives are just as legitimate methods of acquiring knowledge as instrumental recordings, quantitative reasoning and formulation.

Matthew Harwood said...

David Apatoff - "I have to admit that at heart, I am a "drawing" kind of guy."

I agree. I find I draw to discover something for myself and paint to explain it to others

gutscheine zum ausdrucken said...

guter Kommentar

अर्जुन said...

Watch it! I've done all I can to refrain myself from linking to the Moody Blues.

""Which, I guess, only serves to underscore that drawing is inseparable from design which is inseparable from conception.""

From the French dessin translates as both drawing and design.

""watery for Fawcett as you are."" ~ Cue the Kleenex™.

David Apatoff said...

Kev Ferrara-- I'm not sure Russell is saying that "perception, qualitative reasoning and narratives" aren't legitimate; it's just that they don't help us understand the whole counter-intuitive cosmology of multiverses and quantum phenomena and ghosts and cosmic turtles and other crazy things out there beyond our sensory grasp. Even for things within the range of our perception via our subjective sense and emotions, we lack the tools to discover a whole lot about them, don't we?

Matthew Harwood-- That's interesting. So I take it you're one of those who communicates with others by saying, "Do I have to paint you a picture?" rather than, "Do I have to draw you a diagram?"

gutscheine zum ausdrucken-- Danke.

अर्जुन-- I'm sure that Kimberly-Clark appreciates the "TM."

kev ferrara said...
This comment has been removed by the author.
StimmeDesHerzens said...

Goethe's studies of color began with experiments which examined the effects of turbid media, such as air, dust, and moisture on the perception of light and dark...
~"Newton viewed color as a physical problem, involving light striking objects and entering our eyes. Goethe realizes that the sensations of color reaching our brain are also shaped by our perception — by the mechanics of human vision and by the way our brains process information. Therefore, according to Goethe, what we see of an object depends upon the object, the lighting and our perception."

Not my wording, I found it at...
http://www.webexhibits.org/colorart/ch.html

es ist schon lange her.
gruesse zu meiner bester Schreiber

StimmeDesHerzens said...

I also suddenly realized that I missed your Valentine post, but I looked at it just now--prefer the roses and tigers etc. You know my taste, the victorian fluff. One of these days...
ok?

I was in Deutschland, ich war begluckt. Doch mit Schnee und grau, die Farben waren versteckt...

António Araújo said...

Colors only happen in our minds, and Newton already acknowledged that - in the "optics" he knows perfectly well that light is merely the cause of the sensation of color, but is not color itself. The CIE color space is not a measurement of "hard", "objective", physical stuff like a photon's frequency. Rather, it is a measurement of the reactions of human subjects to light spectra under controlled conditions. There is a long history of the measurement - both qualitative and quantitative - of human sensations. The works of Hermann von Helmholtz come to mind. But of course, you start by understanding the causative agent - light.

In very rough terms, I picture the mathematical relation between light with color thus: a light wave is more or less identifiable with a continuous curve (or at least a very fine histogram on the interval of visible frequencies), meaning the sum of all the frequencies your eye is getting from a certain small solid angle. Now, the space of all such curves is more or less infinite-dimensional (or very large dimensional, depending on how much resolution your eye/visual brain has).
However, it is an empirical fact that humans seem to project that infinite dimensional space onto a 3-dimensional space. "A Color" can be defined as the equivalence class of all the spectral curves that are perceived in the same way (by some "idealized" human, since of course not all of us work exactly the same)

Why 3 dimensions? That's just physiology, and that's only in humans (and I hear maybe some humans have 4 color dimensions, in fact). If you performed the CIE experiments on other critters you would get very different color spaces, with different dimensions and forms. That alone should show you that color is all about physiology.

A fun detail is how we close the segment of frequencies onto a loop - Newton's intuition closed it in a color circle, the CIE experiments show it to be more like a horseshoe shape, with the purples being somehow special, not corresponding directly to any single frequency wave but only to mixtures. This closed loop is not a property of light but of our perception.

Now, this mathematization of perception is of course of a very particular type of controlled perception - basically something like a human looking at a uniform color patch at the end of a dark tube (a small solid angle). If you are looking at a real scene in ordinary conditions then the color patches will interfere with each other in your brain in conditions that are far more difficult to describe. One of the things to take into account is precisely the ambient lighting conditions (colors by candlelight or by day, so to speak :))

But you got to start somewhere.

Personally the CIE stuff, with all its limitations, made a bit of light in my head, in a field where art education is usually a horrible mess. My art teachers always recommended the books of Itten and Goethe to their students, which are a prescription for obfuscation and confusion, and completely ignored Newton, CIE, and even Munsell.

Anonymous said...

henry hensche turned form with color not value

António Araújo said...

Oops. corrections: I didn't mean "any continuous curve". Not even curve. I meant just any function (discontinuous is often the case).

Sleepy.

StimmeDesHerzens said...

RE "My art teachers always recommended the books of Itten and Goethe to their students, which are a prescription for obfuscation and confusion...."

Wow that is somethun, where were you studying art? Goethe was sort of like our Benjamin Franklin, a man of all seasons; literary, artistic, scientific... He loved illustration, but more as a pastime since his talent was more underwhelming compared to his ability to create poesie. However art/illustration was part of the educational curriculum in his days. Everyone drew. There were no digital cameras! Is art an increasingly lost art?

António Araújo said...

Stimme,

I'm not dissing Goethe, I even liked his Faust :) (though I prefer Marlowe's, who doesn't ramble as much and is far more enjoyable - wait, have I just digged myself a deeper hole? :)), but the fact that Goethe is such a sacred cow (and the fact that I do enjoy a polimath) to not just his countrymen but even my own (I studied and live in Lisbon) that doesn't make his theory of color any less wrong. Poetic credentials don't carry over to matters of fact.

And it was hardly a past time for him, as he stated himself that he expected his theory of color to endure as among his greatest work. But the fact is that he got it wrong. Am I being unfair to him? Hardly. He proposed a "theory" of color in direct opposition to Newton's (about who's own theory, which he never understood, he had the harshest things to say) and history proved him flatly wrong where he contradicted Newton.

Now, I am not suggesting that people read Newton's "Opticks" to learn about color. It is very old and hard to read and I suppose Goethe's style is more to the liking of a general audience. But I do find it strange that a teacher would suggest - not as reading material of historical interest but as a main source for learning - the book of the guy who, sorry again, got it wrong. And again, sorry ,but wrong is wrong; scientists have no patience for credentials and I don't care how great a guy Goethe was, but he was wrong about this and you shouldn't feed students nonsense without warning. It has been a long time since, and art teachers had enough time to come up with notes that are at least as rational in their treatment of color as, say, the kind of texts that color TV technicians can access - or car painters, or textile painters for that matter (some very good papers on color theory have been written with that audience in mind and in desperation I took refuge there for a while)

And it doesn't matter where you study art, you hear a lot of nonsense about color, because art teachers go around with color "wheels" of all sorts, with wrong theories on mixing and with very few exceptions you are more likely to hear that "three colors generate all the rest" than to hear about, say, the CIE experiments (with luck you'll hear about Munsell). Or, you are much more likely to hear crappy rules of thumb like "don't mix with black because it kills color" or "mix with complementary to darken" than to learn what a shading series is and how to paint one or how to use black properly.

Well, rant over. But I'll leave you with Bruce McEvoy, who put it better than I ever could, about Goethe's book:

http://www.handprint.com/HP/WCL/goethe.html

...and don't get me started on friggin' Itten! :)

I'm sorry if I'm bitter about this, but I have very little patience for teachers who impart ignorance for more generations than is reasonable. Bad texts and bad teaching is one of the reasons we take so much time to learn stuff and can't all be polymaths.

David Apatoff said...

StimmeDesHerzens-- I understand about valentines with tigers and roses. This year's valentine didn't create nearly the same commotion (both from those who liked it and those who detested it). But someone pointed out that in the few years that I've been doing this blog I've had not one but two valentines about love being a source of solace and redemption in the path of a world-destroying meteor (here and here ). I guess that tells you something. Next year I promise I'll move back to roses (if a meteor doesn't destroy us all first).

David Apatoff said...

Anonymous-- Henry Hensche is a new name for me. I checked out his paintings, which are interesting, but I will have to dig deeper to find an explanation for the point you make.

António Araújo-- I am always delighted to have the rigor of the hard sciences introduced in these posts (which too often lapse into subjective liberal arts musings) but we must still regard science's contribution with humility. You say, "Colors only happen in our minds" but ever since Descartes, science has been unable to prove there is anything that does NOT happen "only in our minds." In that sense, philosophy / logic has always held the trump card over science, just as David Hume's philosophy has always held the trump card over causation.

I know, I know, we muddle along as best we can with an uncertainty that will never go away. But the scientific approach to color, like the scientific approach to time, interests me in particular because in both areas we have developed astonishing levels of precision in quantifying a surface phenomenon that is completely untethered to any kind of reality beyond our unsupported sensory impressions. Dazzling advances in precision laser spectroscopy have given us the strontium optical atomic clock, but what the hell does any of it mean? (Or as Walt Whitman-- a poet to rival Goethe-- noted, "The clock indicates the moment - but what does eternity indicate?") I sincerely enjoy your recitation of what we know and what we think we know, but if we pull back from this elaborate, internally consistent construct, don't we find that it is a mere crouton floating on the surface of some vast cosmological stew, offering no understanding of what burbles below?

As you say, "you got to start somewhere," and I think the knowledge you describe is a laudable achievement resulting from many fine minds working at common purpose over time. I would just add that if we keep a sense of proportion regarding these mathematically sound conclusions, we might still conclude that Elizabeth Barret's Browning test (Will the colors coax a loved one into bed, or a customer to buy a product?) remains the most relevant test of all.

Anonymous said...

David here is a link to a pdf. with a little information about henry and his painting approach. http://blueridgeartist.com/media/pdfs/Henry_Hensche_Colour_Study.pdf

Anonymous said...

I did not know henry personally but a friend of mine studied with him for many years. A lot of the people who studied with henry were extremely devoted to his teachings on color. And today you get many different views on what henry actually taught. The connection kinda goes like this William Chase to Charles Hawthorn to Henry Hensche where basically it ends with Henry.

António Araújo said...

David: I'll rephrase it. "Colors only happen in our minds" *even if* you are a "realist", that is, the kind of person that thinks that some things have existence outside of our minds.

That is, colors are only mind constructs even for those physicists who imagine that a photon and its frequency are real things with actual existence in an actual physical world.

As an aside, I agree with Bertrand Russell: solipsism may be logically unassailable but is nonetheless a type of madness.

I would add that I think the logical unassailability of solipsism is a symptom not of its strength but of the limits of classical logic. I can mount a strong case against solipsism if I use generalized logic - that is, bayesian probability - and decision theory to consider not only the logical status of the theory, but its probability of being true and the consequences of taking it for true if actually false.

In brief: Are you real or a dream I am having? Since logic cannot prove it either way, I might give both hypothesis equal probability. But then I have to consider the price to pay for a mistake. If I take a dream for real life, there is not much I lose. But If I take real life for a dream, what a waste...and what danger! Therefore decision theory will tell you that solipsism is a fools wager.

There is a principle of precaution at stake; I am reminded of those Cartesians who merrily tortured animals and laughed at the fools who cringed and wept at the inflicted cruelty, because the poor ignorant souls did not understand that Descartes had proved animals to be mere machines with no soul and therefore no feelings or sense of pain.

António Araújo said...

As for your other statement, I fully agree. I remember that in fact we once had a discussion on whether digital painting was real Art or not, and I gave you an empirical test for "real Art": whether or not it gets the girl into bed.

I think we all agree that nobody ever got a girl into bed with a wacom tablet in hand :). That is why oil, brushes, charcoal and so on can be shown to be required for real Art to happen :)

David Apatoff said...

António Araújo-- I enjoyed Bruce McEvoy's lively discussion of Goethe's color theory but it became apparent at the very beginning (when he described Goethe's profession as "bureaucrat") that we were not in store for an objective, dispassionate treatment. McEvoy is clearly still fuming over Goethe's assault on McEvoy's hero, Newton. I understand his resentment; Newton is one of my great heroes too (but he was also a mystic wacko). And McEvoy's disdain for Goethe's amateur empiricism seems misplaced, since so many of the great discoveries of the era came from curious amateurs.

Goethe deserves credit for being a poet of magnificent stature. If you want his real contribution to color theory, look at these lines from Faust, where darkness confidently states that it began the world and will end it:

"I am a part of the part that at first was all, part of the darkness that gave birth to light, that supercilious light which now disputes with Mother Night her ancient rank and space, and yet cannot succeed; no matter how it struggles...."

In these lines you see the conceptual precursor to modern existentialism, as well as to Bertrand Russell's quote about the limits of math in physics. That's one heck of a color theory.

StimmeDesHerzens-- Willkommen zurück. Es ist gut, wieder von Ihnen zu hören. Und ich liebe auch Goethe.

Anonymous-- Thanks for the article on Hensche. I found it very interesting. It became clear the author took Hensche's samples very seriously when he wrote, "This document will NOT print accurately as displayed. The settings are RGB, not CMYK and the jpg saturations and
contrasts do not automatically convert to printable settings." That may be a level of refinement that eludes the common viewer.

David Apatoff said...

António Araújo-- Agreed, although I want to note for the record that my test was coaxing a "loved one" into bed, not "getting the girl into bed." I know that as a scientist, you would appreciate the universal applicability of a color theory that makes no assumptions regarding the gender of the artist or the gender of their heart's desire.

António Araújo said...

David, you'll notice I made no assumptions about the gender of the artist, but only of the one desired. You see, if a man was the object of interest, you would need no art to lead him to the bedroom - we brutes are simple folk :)

About McEvoy, I enjoyed his venom and I don't think it can take away from his very careful analysis of the facts (though yes, it may make you suspicious, but you can check by yourself). And I hold no special love for Newton as a person (he could be a bit of an asshole), but he *was* right, and it is about time some people in the 21st century with teaching responsabilities got that into their heads. I think the venom was aimed at those living people (and not at the corpse of a poet) who not only refuse to look through Galileo's proverbial telescope but who don't acknowledge its existence at all. Goethe, by the way, did just that sort of thing - and it changes nothing that we all acknowledge he was a great poet - his poetry is not the issue.

>"I am a part of the part that at >first was all, part of the >darkness that gave birth to light"

Great poetry perhaps, but I disagree with you about it being great color theory, the problem being precisely that he took it literally. Back to McEvoy:

"In rebuttal, Goethe reasserted the ancient theory, commonly attributed to Aristotle and inherited from medieval optics and early Baroque naturalists, that color results when light comingles with dark. He lists as the basic tenets of this position that "white" light is simple and homogenous (he calls sunlight the "Urlicht" or original light); that colors are caused by the "shadowing" or darkening of this white light; that it was therefore absurd to conclude that light could be reassembled from darkness; and that there are not seven but only two "primary" colors — yellow and blue — that emerge first from the light and dark mixture ("Instead of An Epilogue", Unmasking Newton's Theory). These points comprise what I'll call the factual disagreement with Newton."

By the way, I actually met, to my horror, an art student who thought that "colors are the darkening of white light" and that "there are two primary colors" were factual assertions. Then again, most people I meet still think that there are 3 primary colors and that these generate all others by mixing, so maybe my horror should be more diffuse....

David Apatoff said...

António Araújo wrote: "if a man was the object of interest, you would need no art to lead him to the bedroom - we brutes are simple folk."

Well, I can't argue with that.

But I think you may be applying the wrong test of the veracity of Goethe's poetry. I'd say the "color theory" behind Mother Night goes beyond whether color results from commingling light and dark, and goes to the more ontological question of why there is light as opposed to nothing. We're not talking about "black" on some color wheel, we're talking about the existential void.

António Araújo said...

>But I think you may be applying the >wrong test of the veracity of >Goethe's poetry.

Let's say I look at it through a different prism :) (according to whether I'll read it in the context of his Faust or in that of his most curious color-theory "masterpiece". :))