Some of you may be familiar with the work of James Gurney. He is the artistic genius behind the Dinotopia books. I stumbled across his blog yesterday and found a most fascinating three part article on color theory and the color wheel. Now for someone who is relatively color challenged, I found this to be very interesting. I wrote asking if I could link my blog to his articles or reproduce the articles. He gave me permission to reproduce the articles as long as I gave the appropriate credit. I would not do anything less. There is a lot more to learn from James on his site and I recommend you explore the site for yourself. It is a gold mine of useful information. You can find him at: http://gurneyjourney.blogspot.com What follows is his three part article.

SUNDAY, JANUARY 27, 2008

Color Wheel Masking, Part 1

Today I’d like to introduce an approach to color that I’ve been developing over the last 10 years. I’m very excited about it, and I’d love to know your reactions. I call it “Color Wheel Masking.” I’m going to show you a practical method that you can use to accurately describe any color scheme that you see.
2b85a1a4ba10495d825a9f24f9504b8c Let’s start with the basic color wheel with the primary and secondary colors are arranged around the outside of the circle in the normal way. As each of these colors approaches the center, it becomes a neutral gray. Any individual color can be pinpointed on the surface of the wheel in terms of its hue and chroma (“chroma” is also known as “intensity” or “saturation”). For the moment, we’re ignoring value as a dimension of color. If a single color can be charted on the circle, then it follows that the whole scheme can be charted, too. To chart an entire color scheme, it helps to think not only which colors are included in a composition, but also which colors are left out. Let’s look at some actual pictures to see which colors are in and which are out of the color scheme.
Red-Green-Palette On the left is a photo of some roses and leaves; on the right is a Christmas painting by Norman Rockwell. Each of these painting has greens and reds in different distributions. Both essentially lack yellow, orange, violet and blue.
BlueVsOrange Here’s another photo and painting paired together. What they have in common is blue and orange—but no red, no yellow, no yellow-green.
Two_Color_Schemes Here are two more pictures. Their color schemes are not identical, but basically they’ve got strong reds and yellows, some greens, and a dull blue-violet. What they’re both missing are full-intensity blues and greens.
RockwellB copy Now let’s see if we can design a mask to fit over the color wheel to fit these schemes. We want the mask to show only the colors we see in the picture and to leave out the colors that are absent. The Rockwell painting is pretty easy, because it only includes greens and reds (plus a hint of blue in the package and very dull yellow in the ribbon). The color mask here is a long diamond shape that includes the complementary colors that oppose each other across the middle of the wheel, leaving out everything else.
BlueVsOrangew.Wheel Here are the images with the blue-orange polarity, along with a masked color wheel. Note that inside this diamond shape, there are some other colors near the center: just a hint of red and a touch of yellow-green and blue-green. The colors inside the perimeter feel sufficient for a complete color scheme, even though we’ve left out a lot.
IMG_2822 The mask doesn’t have to be this long diamond shape, because not all color schemes are complementary. Nor does it have to go all the way to the edges, because plenty of paintings lack full-intensity chromatics.The mask can also be a small triangle in one part of the wheel. Here I’ve taken two paintings from Dinotopia: Journey to Chandara and mapped out their color schemes by digitally defining a shape on the wheel and ghosting the rest.

Wheel demos

The swamp scene has dull yellow-greens and browns (browns are really dull oranges). The colors can be contained in the small triangle. The corners of that triangle never touch the edges of the wheel, because the painting doesn’t have any colors of full intensity. As you can see from the ghosted perimeter, the color scheme excludes blue, purple, and red. Now all of a sudden we have a great way to describe any existing color scheme. But that’s just the first application of color wheel masking. Next Sunday I’ll show you a range of shapes for color wheel masks. Following that, I’ll describe exactly how to use color wheel masks to generate and experiment with color schemes.

In the intervening time, if you get a chance, I recommend that you can paint or digitally create your own color wheel to use as a tool for your own experiments.

SUNDAY, FEBRUARY 3, 2008

The Shapes of Color Schemes

Last week I introduced the concept of color wheel masking, and suggested that any color scheme can be represented or mapped as a shape on a color wheel. Let’s take that idea and run with it.
Triad.sm
I painted the wheel at left, below. As you recall, it has the full-intensity hues arranged around the outside edge, gradating to neutral gray in the center. It uses the traditional subtractive red-yellow-blue pigment primaries. This painter’s color wheel goes back for centuries, and was influenced by the theories of Goethe and Newton. Two of the astute commentators on this blog, ZD and Painterdog, correctly pointed out that the traditional painter’s color wheel is technically obsolete and even somewhat arbitrary and dogmatic, but I still have a fondness for it.

ColorWheel.ai

On the right is a mathematically correct digital color wheel based on the red-green-blue “additive” primaries of light. Spaced halfway between RG and B are cyan, magenta, and yellow, the subtractive colors used in printing inks. My photographer friend Tobey Sanford created this wheel (downloadable here). It may be less familiar to traditional painters. It places the component colors differently around the wheel, but for the purpose of exploring the world of color, especially on our computer screens, it will serve us better in some respects, and we’ll see it again from time to time on future Color Sundays. Regardless of which wheel we use, most color schemes are built from three component colors or primaries arranged in a triangle called a triad. The area inside the triangle is called the “gamut.” It includes all the possible mixtures from those three primaries, whatever they are.

Mucha_Alphonse_Maria_Madonna_Of_The_Lilies copy

The primaries don’t have to be red, yellow, and blue. You can use any three colors as primaries, even orange-green-purple—which in fact is what early color photographs called “autochromes” used. In the case of the limited palettes we looked at a couple weeks ago, for example, we talked about using a less saturated pigment like yellow ochre instead of cadmium yellow. This reduced or muted yellow corresponds with a point well inside the margin of the wheel. By using a paper mask and rotating it around the wheel, we automatically get interesting reduced gamuts, each with a dominant full-intensity hue and two subordinate, weaker “primaries”.  

3_Rotations
The mask sets us free to choose exactly the color schemes we want. We’re not limited to the haphazard choices of existing tube colors in limited palettes; instead we can use the mask to analyze or invent any gamut. The equilateral triangle that I call the “atmospheric triad” is only one kind of color wheel mask. There are other shapes, and each of these basic shapes carries its own personality, regardless of the component colors. Atmospheric triads are moody and subjective, great for “color scripting” a graphic novel or a film. When you rotate the triangular window around the color wheel, you can see the color groupings change, yet each one seems complete to itself. It suggests the feeling of walking from a room lit by incandescent light into another room lit by fluorescent light, and then stepping outside into the blue twilight. Your brain shifts from one color environment to another. I’ll talk more about the brain physiology behind color adaptation in a future Color Sunday.
Shifted Triad paired
Here’s a color mask that crosses over the center a bit more, which I call the “shifted triad.” It’s shifted toward red, which means the subjective gray or neutral (N) in the composition is also shifted toward red. The secondaries (S) are what you get when you mix the dominant full-intensity red with the weaker blue-violet and blue-green primaries (P).
Complementary
Here’s a complementary scheme, similar to what we’ve seen before. The complementary gamut, regardless of its component colors, suggests an opposition of elemental principles, like fire and ice. At the same time, it’s fairly stable, because its neutral coincides with the center of the wheel.
Mood_and_accent
This one is called “mood and accent.” Most of the picture is in one color mood, with just one accent area from across the wheel and no intermediate mixtures. By the way, note that the octagonal color wheel mask and the color wheel slide into the top of the aluminum U-molding.
Strange_Accent
You could also pick an accent color that’s offset from the complement. It looks less natural, and therefore perhaps more attention-getting. What happens when you create a mask that shifts the color balance off the axis? To me it feels like one of those diminished seventh guitar chords, or a dollop of sour cream dropped into sweet squash soup. What effect do you feel with a split complementary arrangement, avoiding secondaries? To me it seems vibrant and attractive, but also a little unsettled and jarring. What if the mask selects colors all to one side of the wheel? To me it gives a sense of brilliancy, purity, or weirdness, not something you’d find in nature, but great for otherworldly science fiction. There’s no limit to the kinds of masks you can cut, and then the infinite combinations you can generate when you start rotating a mask above your own wheel.
Next week, I’ll show you how to take a gamut you’ve selected, and prepare the paints on your palette so that you can use those exact colors in your own painting. The beauty of this method is that it jolts you out of any color mixing habits, and at the same time it forces you to stay within the limits you’ve chosen.

SUNDAY, FEBRUARY 10, 2008

From Mask to Palette

How do you get exactly the colors you want in a picture….and no others?
Oriana_with_Colors.wt
This is the third post in a Sunday series about a method called color wheel masking. The first post showed how color masks can help to analyze color schemes, and the second post explored different shapes of masks.
In this post I’ll demonstrate how to actually mix the colors you have chosen for a given painting.
Demo1
To start with, here’s the color wheel on the left. To the right above the palette paper are some primary colors of oil paint. You can use as many tube colors as you want at this stage. I just have little demo dabs of Winsor Red, Cadmium Yellow, Titanium White, and Ultramarine Blue.
Demo3
Let’s say you want a monochromatic atmospheric triad with the dominant (and the most saturated) color in the red-orange range. Using your palette knife, mix a batch of each of the three colors that you see in the corners of the triangular gamut. I’ve placed a little white box over those colors in this photo. In this case, it’s a saturated red-orange, a desaturated red-violet, and a desaturated yellow-green.
Demo5
Now you’ve created the “heads of the families” or subjective primaries. Next, extend those colors into four different values or tones. Try to keep the hue and the saturation constant as you do so. Look again at the color wheel mask. Halfway along the edge of the triangle are little marks indicating your secondaries. These are your in-between colors, which you may want to mix as well. You may end up mixing and working with anywhere from three to six strings of colors. Before you start painting, remove from the palette all the tube colors that you squeezed out, except for white. This is important, because these colors are outside your gamut. You don’t want to have access to those anymore during the painting process.
FireEquipment.Color
At left is a color wheel with a monochromatic atmospheric triad emphasizing red. This time it’s laid out on Tobey Sanford’s digital color wheel (link to download). On the far right are the color ranges I mixed. In the middle is the resulting painting from Dinotopia: Journey to Chandara.
Dinotopia_Group_Portriat
This group portrait takes place in Dinotopia’s phosphorescent caverns in the book The World Beneath (1995). I wanted the colors to suggest a cool, magical ambiance. With the colors in this gamut, it’s impossible to mix any intense warms, even if you wanted to. But as your eyes adjust to the color mood, it feels complete. The relative warm colors appear warm enough in the context of the picture. I have noticed that when I use the color wheel masking system I am more careful to keep the brushes clean and to push against the outside of the range. Harmony and unity are a given, so the effort goes into reaching for accents. It’s the opposite of the color-mixing mindset when mixing color from a full palette of tube colors, where I’m always neutralizing mixtures.
ColorWheel.ai
To conclude, here’s a painting from Dinotopia: A Land Apart from Time (1992), about the time when I first developed this method. I have digitally reconstructed the gamut I used for the narrow complementary color scheme.
Blog reader Briggsy provided the diagram on the right. He processed the image through a filter created by P. Colantoni, and available for Windows users at couleur.org. What you’re looking at to the right of the painting above is an objective computer visualization of the actual color scheme.
As you can see, it corresponds pretty closely to the generating mask, proof that the system is giving us exactly the intended color scheme. The blue colors are very intense, almost touching the edge of the wheel. The rest of the colors are in a narrow swath running across the grey center to the weaker complements.
I look forward to hearing how this method works for you, either with traditional or digital techniques.

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