Mixtures are usually lower in chroma than paint straight from the tube. So with just a few paints on your palette, there will be colors you cannot approach, because when you try to mix the right hue you lose too much chroma. One way to deal with that is to simply have a very large number of paints on your palette. That way, whenever you need to represent a high-chroma color, you are likely to have one that is close. You can then get the right color with a minimum of 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.