Saturday, February 27, 2010

The Color Wheel, Part 6

Cyan, Magenta, and Yellow
In the world of printing and photography, the three colors that mix the widest range, or gamut, of colors are cyan, magenta, and yellow.

These “printer’s primaries,” together with black (K), are known by the shorthand CMYK. CMYK inks are used throughout the industries of offset lithography, computer printing, and film photography.

If other industries use CMYK primaries instead of yellow, red, and blue, why don’t painters use them too? One reason is simple force of habit. Cyan and magenta don’t match our mental image of blue and red. These color concepts are deep rooted from childhood.

Can we find these colors as artist’s pigments? Until recently it was hard to find lightfast chemical pigments that would match up with CMY. The pigments Cadmium Yellow Light (known by the Color Index Number PY 35), Quinacridone Magenta (PR 122), and Phthalo Cyan (PB 17) come close. (The Lukas colors above are PY 3, PB 15:3, and PR 122).

Intriguing as this may be, it’s not really the answer. Most of these colors are very transparent, which can be a problem for oil and gouache painters. For painting we need a range of properties, opacity being just one of them. And most of the time we’re not trying to get the widest range of intense colors in a single painting from just three starting colors.

We can add as many starting colors as we want, especially if we want to get a wide range of mixtures. That’s what the top-end computer printers do, as do lithographers printing high quality art reproductions.

We can keep all our favorite pigments, even if they don’t match the printer’s primaries. We aren’t bound to using just three pigments when we’re painting.

But returning to the color wheel, we still need an accurate map to chart our pigments and mixtures. What we’re looking for is a universal way to understand color relationships regardless of the medium or technique we’re using.

CMY circles from Alias 3D Media

Reviewing the posts in this series:
Part 1: Wrapping the Spectrum
Part 2: Primaries and Secondaries
Part 3: Complements, Afterimages, and Chroma
Part 4: Problems with the Traditional Wheel
Part 5: The Munsell System
Part 6: Cyan, Magenta, and Yellow
Part 7: The Yurmby Wheel


Paolo Rivera said...

The Epson printer (R1900) I bought last year adds red and orange ink to the mix ( as well as two kinds of black, matte and glossy). My printer before that (R260) added light cyan and light magenta. All seem to do an equally good job, to my eye.

Also, I've been tempted to produce a painting using just primaries, but haven't gotten around to it yet (at least not since school). Holbein's gouache series lists 3 colors as being primaries... I've only got blue so far.

Looking forward to the next installment.

jeff jordan said...

I remember an artist by the name of Don eddy, a photorealist from the 80s, who did all his paintings using basically CMYK colors. Too mechanical for me, but it sure worked for him. To each his/her own.........

Don Cox said...

Quentin Blake illustrated a book of verses by Hilaire Belloc, using just CMYK inks.

I don't think CMY do a good job of rendering skin colours, for which iron oxide pigments such as Siennas, Umbers, Venetian Red, etc are best. Indeed, I would say these are the most useful pigments for painting altogether.
But they don't fit on any simple colour circles, and you can't get them on a computer.

Michael Dooney said...

The lukas colors seem like a good idea. I did several paintings using only Golden's 3 "primary" colors and while it was interesting and fun to work with that limited palette, the paints themselves are only part of the issue when working for reproduction. I've found that the hardest issue to overcome is the step between the painting and the press, be it the scanner or photography. I would love to see you do a post on what steps you take with your paintings AFTER you paint them... I assume that you are photographing and not scanning your art???

donna said...

I have a water color set where the basics are cyan, magenta and yellow. Not that I've painted in ages, but I have them...

Roberto said...

When I first started exploring color I learned that the primary colors for pigments were Red, Yellow, and Blue, but that the primary colors for light were orange, green, and purple. I was skeptical so I got some color gels and projected colored light with an overhead projector and, sure enough!, I could make red light from purple and orange, blue light from purple and green, and yellow(or amber) light from green and orange!! (but I couldn’t make green, orange, or purple from red, yellow, or blue light). This convinced me… until many years later when I had a conversation with a real brainiac optics/scientist guy (I think he was Hubble’s optometrist or something) who pointed out to me that colored lights do not interfere when mixed, the wave frequencies don’t change when mixed! This really blue my mind! The only conclusion I could make was that when I mixed purple and green light together and saw blue light, it was literally all in my head (eye/brain)! You are right when you say
< no color from the original spectrum has any higher claim to be a primary color than any other. Each hue occupies an equally legitimate place on the outer rim of the hue circle and can claim full status as a primary color. Nor are any particular hues by their nature secondary colors. Green is not a composite color any more than blue is.>
but… pigments are a different story. You can create secondary colors (G,O,P) from primaries (R,B,Y). but not vise/versa. As Thomas Kitts said...< there is one thing you cannot do with paint - any paint at all -- and this is, increase the Chroma of a color by mixing two or more colors together. Chroma always goes downhill, which is why, if you need a certain intensity then you must start with intense colors.>
( although that bit about < What I don't allow my students to use in my classroom are terms such as "Shade" or "Tint" because both words can be confused with Value, Hue, or Chroma. Or confused with a combination of all three.> is a little over the top, in my humble opinion.)
Your exercise in part 4 … < You could set up a palette with high-chroma orange, violet, and green as primaries and paint a satisfactory image from them> is painting with a triad of secondaries (not primaries) resulting in a composition of tertiaries ( The red in the orange intensifies the red in the purple, while the yellow in the orange and the blue in the purple mix into a graying green for the mixture); a beautifully subtle limited pallete and
a good painting exercise. But lets not start a Lilliputian battle over technicalities.
I tend to agree with ‘bunky’ said… and I would add that since it is the industry standard in the commercial house-paint industry, it makes it much easier to match colors when working with interior decorators and interior designers.
( I guess that make s me a Fundimunsellist, but I’m not a Radical Fundimunsellist) Munsell condenses yo-o-or into yr(o?), compressing the transition between y & r from 3 steps to one step, thus mapping the ‘Color clock’ closer to the perceived spectrum you show in part 4, and also shifting the ‘primaries’ from r-y-b to bluegreen(Cyan) - redpurple(Magenta) –Yellow, or CMY similar to ink(print) media’s CMYK; and closer to your after image color chart (in part one). I really like your overlapping star diagram for representing the tints and tones, but I don’t like limiting the orange (warm) values, (as pointed out by ‘etc.’), it throws off the warm/cool balance of the 12 stepped color wheel, and also shifts the red/green-yellow/purple opposition which I find very helpful. My tendency is to stick with the 12 color wheel and incorporate Munselle’s Tints, Tones (earth tones when possible) and Shades (I don’t like using black, except when all else fails), with the addition of warm and cool pigments for the primaries, as Allen said...
End of essay.
Looking forward to your conclusion with an open mind and baited breath -RQ

Paul Corfield said...

To Jeff Jordan,
Don Eddy was an airbrush artist who used the colors pthalocyanine green, burnt sienna and dioxazine purple so not quit cmyk but he did restrict the colors he used. Plus using the airbrush meant he could utilize the colors transparent properties.

Most of my own paintings start out with a magenta or rose, pthalo blue and winsor yellow. I may add cad red, cad yellow and cad orange to warm things up but that's about it. Before painting in oils I spent quite a few years working in airbrush where I only used three transparent colors as close to cmy as I could get. That's probably why I work with a restricted palette now as I'm very used to it.

Erik Bongers said...

This must be the most scientificly correct series on colours written by an artist.
Combined with some practical wisdom and experience (like the opacity problem of painting in cmyk) this should be standard colour theory for 1st year art students.

Unknown said...

I use 4 colors,CMYK for my 4 color printing it is more effective in printing prints.

Unknown said...

I've found it quite difficult to find lines of oil colours that carry Phthalo Cyan PB17. Charvin is the only one I know of that has it -- the rest that come close seem to be hues mixed with PB15:3 and various whites.

Anyone know of other brands carrying it?

blu_in_green said...

Echoing Richard. Can you tell us what you use in oil for PB 17 (pure pigment or a mix a la PB 15:3)?

James Gurney said...

Richard and Baker, I really can't remember which pigments I used. I had several brands and several pigments out as I mixed each swatch, and tried to use the highest-chroma I could find for the value I needed. You could mix a swatch with various recipes, and then just pick the one that had the brightest color.

blu_in_green said...

Thanks James! I've been studying to your book "Color and Light" lately. I haven't had much luck finding any brands with Phthalo Cyan (PB 17). This seems have perplexed others on internet forums as well!

The closest in number appears to be PB 16 under different names, but the hue seems very different from what is labelled Phthalo Cyan in your figure on page 102. In your figure PB 17 looks nearly Viridian.

Any thoughts on finding a PB 17 (or other standard cyan) oil pigment on the market these days (rather than cyans sold as pre-mixed)?