The portrait from the first week was pretty awful. Last night’s was not exactly good, but not nearly as bad. Maybe I’ll post them when I have something a little better to compare them to.

This is the first work I’ve done with portraits or figures in about three years, so I am not surprised that some of my skills have gotten rusty. One skill that has improved, however, is mixing flesh tones. I remember, when I was taking figure painting classes, having a heck of a time getting flesh tones that looked even approximately convincing, even when I could take my time over a multi-session pose of 9 or 12 hours. The poses I’ve been working from lately are only 2.5 hours, but I now find paint mixing to be relatively straightforward.

Because these are pretty short poses, I have not worried too much about getting exactly the right hue, instead choosing to concentrate of value, chroma, and shape. I’m working with a very limited palette in which flesh tones are mixed from lead white, raw sienna, burnt sienna, and raw umber. (I’ve also used some black and some ultramarine for dark hair and background.) The flesh tones are basically convincing, however: others at the session have remarked on it and my wife, who remembers my previous struggles, has mentioned that these flesh tones seem better. I should note that, thus far, the subjects have been Caucasian, although I don’t think I would have any greater trouble painting folks of less pallor.

I’m not sure why this aspect of painting has become easier, except for all the practice I’ve put in mixing still life colors over the last couple of years. The very simple palette seems to help as well.

Now if I can just get the shape of the head down correctly in paint, I’ll be just fine.

Update

7 May 2009: On further reflection, I think that one of the things I’ve learned over the last couple of years, even with a very limited palette, is much better control over chroma. Many artists mix overly intense skin tones. Most people’s skin is very low in chroma. Even when using relatively dull earth colors, you often need to cut the chroma of your mixes to get accurate color. For these portrait studies, I’ve been using raw umber for that purpose, as it’s chroma is very, very low.

Usually, what I do when painting in oil is work with two brushes—one for the lighter sections of that passage and one for the darker parts. The value may have a wide range or a narrow range, but either way it’s helpful to have one brush for each purpose. That’s useful, I think, for two reasons. One is the simple technical point that it’s easy to keep track of two brushes, loading, applying, wiping, mixing, and re-loading. It’s a lot quicker to change the paint on a brush from a dark to a mid tone than it is to change from a dark to a light.

The other way that working with a dark brush and a light brush is in terms of thinking about light. As I’m working on a passage I can think about how the light is affecting it at a particular point. If the primary thing happening is that the section I’m working on is turning toward the light, then I automatically grab the light brush. If it’s turning away, then I grab the dark brush. I find it useful to think in that binary way because that’s how light works: a given point is either toward the light or away from it compared to nearby parts of that passage. By working with two brushes, I always keep that in mind.

Saturation runs on the same scale (often 1–100) regardless of the hue or the value. So the most intense blue, no matter what, is a saturation of 100. The most intense yellow, similarly, has a saturation of 100. That’s very convenient for people who design software interfaces. And if you don’t really understand color, it makes perfect sense. What it doesn’t do is model color accurately.

In reality, the most intense yellow is far more intense than the most intense blue. And the highest possible intensity varies depending on how light or dark the color is. The most intense yellows are found at a relatively light value. The most intense blues occur at somewhat darker values. At very high and very low values, maximum chroma goes way down. But you can always set the saturation to 100 to get the most intense color at the hue and value you have currently selected.

Chroma runs on a different scale. In Munsell, the most intense chroma for yellow runs up to about 18. The most intense blue is more like 12. (I’m doing this from memory, so these numbers might be a little off.) Those numbers change with hue and value, so that the Munsell color space is an irregular, lumpy cylinder. That is a much more accurate depiction of human color vision than the saturation model. It helps to think about color in this way when you’re trying to understand actual color relationships.

Update and Correction

28 February 2008:

David Briggs, in comments to this post, writes:

To clarify, David, my objection is that you seem to be judging saturation as if it was meant to be a measure of colour intensity. It isn’t, it’s a measure of colour purity. The term for intensity of colour of light is “colorfulness”, the product of the saturation of a light stimulus and its brightness.

Many colours reflect light of high saturation, but only those that reflect light of high colorfulness (high saturation AND BRIGHTNESS) have high chroma. RGB colours that emit maximum saturation red light range from very low chroma (nearly black) through moderate chroma (dark ruby reds) to very high chroma (bright red or R 255). The importance of this concept of saturation for painters comes from the fact that when a coloured surface turns from shade into light, the colours of the light reflected from it tend to follow a uniform saturation series such as this.

And darn it, he’s right. Thanks, David. As this Wikipedia entry on colorfulness puts it:

colorfulness is the perceived difference between the color of some stimulus and gray, chroma is the colorfulness of a stimulus relative to the brightness of a stimulus that appears white under similar viewing conditions, and saturation is the colorfulness of a stimulus relative to its own brightness.

I, with my obviously very small brain, still find it most useful to think about color using the characteristics of value, hue, and chroma. But saturation does not mean what I said it does. I apologize for any confusion.

I agree that indiscriminate reliance on high chroma leads to discordant, brassy, loud paintings. But the alternative of matching the chroma of nature is not, in my opinion, the best solution. Since paints have such a limited range of value and chroma compared to nature, painters who try to match nature’s colors exactly wind up with a dull, dim picture. This is most evident in a clear blue sky. No paints can mix a blue that is as intense and yet as light in value as that sky. Only by selectively and artfully exaggerating the chroma relationships and value differences observed in nature can a painter approach the color relationships we see in nature. I’m not speaking here of the expressive exaggeration of color for emotional effect, but simply of painting a realistic picture of the scene before you.

I don’t think there’s much disagreement between us. My objection is to artists who use high chroma thoughtlessly, because they think that a painting that consists entirely of intense colors is “prettier” or more “exciting” than one that is more modulated, or because all of the paints they own are high in chroma and they never learned how to mix them to get a desired chroma.

If I might be indulged in quoting myself, here’s what I wrote in an article on color mixing:

Let me give you an example. I was browsing through art books in a bookstore the other day and found one about the painting techniques of the impressionists. It’s a very well written book, based on lots of research on the individual methods of many 19th century artists. There are a number of demonstrations in which the author copies a section of an impressionist painting, using the methods of the original artist. In every single case, throughout the entire book, the author gets the chroma badly wrong and pretty much everything else right. In particular, almost every color is one or two chroma steps higher than the corresponding color in the original. Impressionists were not known for making dull pictures, but the author felt the need to “improve” the originals by bumping the chroma, even though she was clearly making a serious attempt to use the same or similar pigments and techniques. What’s more, I don’t think she knew she was doing it. I think she believed she was doing precise copies, but failed to see chroma differences right in front of her face. That’s just a guess on my part; some of the pigments used in the typical impressionist palette were fugitive, so she might have been deliberately compensating for their tendency to fade. But if that’s the case, I couldn’t find where she told us that, and she was certainly increasing the chroma even in areas corresponding to those painted with lightfast pigments. So either the reproductions in the book are badly messed up (and no one caught it) or this artist has a remarkable insensitivity to chroma.

I see similar errors on internet forums in which amateur artists post copies of old master works. The chroma is usually too high—often much, much too high. That might have something to do with how the work has been photographed, digitized, and presented on computer monitors, but in case after case, the posted copy appears consistently more chromatic than the original, even when the artist has shown them side by side. The artists usually seem unaware of this difference, and sometimes have trouble seeing it even when it is pointed out to them.

Decker’s example of pushing the chroma in the sky because you just can’t capture the chroma and value in paint at the same time is an excellent one. It makes me think of Maxfield Parrish, who painted skies with high chroma, but never cluelessly.

• High chroma colors make up most of the patient’s paintings.
• The patient might agree that a symphony that consists only of high notes would be excruciating to listen to, but thinks that a painting that consists only of high chroma colors is “colorful” and “exciting.”
• The patient doesn’t actually know how to adjust the chroma of mixes. In severe cases, the patient may apply only straight tube colors to your paintings, without ever mixing.
• The patient never uses earth colors.

Please give generously to the International CCS Institute. CCSI doctors are working tirelessly, day and night, to develop new and innovative treatments for this debilitating disorder.

Related article

Color and Color Mixing

My teacher, Dennis Cheaney, uses this approach. It is based on the method advocated by Ted Seth Jacobs, his teacher. Here’s what Ted says about this in “Light for the Artist,” the book I’ve quoted from in a number of posts.

Some painters prefer to work with the fewest possible colors (called a “limited palette”). The disadvantage to this method is that mixed colors are not quite as chromatically intense as their counterparts out of the tube. For example, an orange made of red and yellow loses some chromatic intensity as compared to tube orange. The limited palette reduces our available chromatic range.

Another one of Ted’s students, Tony Ryder, was profiled in a recent article in American Artist. His palette for one painting has 47 paints on it:

flake white, misty blue, zinc white, titanium white, Naples yellow green, jaune brilliant, Naples yellow light, Naples yellow, Naples yellow red, cadmium yellow lemon, cadmium yellow, cadmium orange, coral red, brilliant pink, cadmium red, cadmium red scarlet, alizarin crimson, rose grey, cobalt violet, cobalt violet light, Winsor violet, ultramarine violet, cobalt blue, king’s blue, ultramarine blue, cerulean blue, cobalt green light, viridian, green grey, chrome oxide green, cinnabar green, Bohemian green earth, sap green, yellow ochre light, yellow grey, raw sienna, Old Holland ochre, deep ochre, raw umber greenish, mars yellow, mars orange, burnt sienna, mars violet, burnt umber, Van Dyke brown, Payne’s gray, ivory black.

That’s a lot of different paints.

I don’t claim to know more about painting than Ted Seth Jacobs, Tony Ryder, or Dennis Cheaney. But at my limited level of skill I do see a couple of problems with this approach. One is simply that it is much harder to learn the mixing characteristics of 47 paints as well as you can with, say, 6 paints. When mixed, pigments react in unpredictable ways. If you use a more “limited” palette, you can learn with great specificity the ways that each color mixes with every other color. If you don’t really know your colors, then you’ll often be surprised at the results of any given mixture. What you end up doing is having to fiddle with mixtures. You mix two paints, observe how the color shifts, then add another paint to compensate for the color mixing shift that you didn’t predict, then maybe have to do that once or twice more before the color is exactly right. As that happens, the chroma inevitably goes down. So you might have to then try to add some more of a brighter paint to pull the chroma back up. With this approach, you can spend a lot of time chasing color.

In his book, Ted also points out how mixing colors reduces chroma, but fails to account for that when he is selecting paints containing multiple pigments. In describing the value of a kitchen sink palette, he shows five different greens: gray green, sevres green, cobalt green light, cadmium green light, and olive green. The book was written awhile ago and he doesn’t say what brands he is using, but I think that at least two of those are multi-pigment paints. There is no such pigment as “cadmium green,” for example—it’s usually a blend of cadmium yellow and pthalo blue. Similarly, a number of the paints on Tony’s palette also contain multiple pigments. If the rationale for the large number of paints is to avoid chroma reduction from mixing, then I don’t see how it makes sense to choose paints that the manufacturers have already mixed for you. Paint companies don’t have any special way of mixing paint without the saturation costs that we have to cope with when we do the same thing on our palettes.

That is not to say that any of these guys don’t know how to mix paint. I’ve watched Dennis do it, and it’s impressive. In a few seconds, he’ll pull several colors together to produce a mixture with just the right value, hue, and chroma. But when I put that many colors onto my palette I get all mixed up. I lose track of which colors I’m using for what purpose. When mixing, I find myself either (a) using too many different paints in each mixture, chasing color all over the place, and tossing some mixtures and starting over; or (b) ignoring most of the paints on my palette and using only a few.

Nevertheless, some artists can manage a large palette of paints without apparent difficulty. Ted, Tony, and Dennis do it brilliantly. But it is not an approach that works for me.

Related article

Color and color mixing