I just finished writing an article called "Extreme Limited Palettes" for
International Artist magazine
and I want to preview one small part of it for you.
The article will include these four color charts. Each diamond-shaped diagram represents the possibilities of three colors, plus white.
Each diamond shape is composed of two isosceles triangles. The left triangle represents the gouache colors straight out of the tube, and the right one represents the mirror image of those colors, but mixed with white. Secondary mixtures appear as rectangles along the side of each triangle. The darkest "black" you can get from those colors is the small dark patch in the center of the left triangle.

Each chart gives a sense of the full available gamut for that limited palette, so you can see at a glance what's possible with a given set of colors.
For example, you can see how this painting belongs with the chart in the upper right, the one with yellow ochre
(Holbein), perylene maroon
(Winsor Newton), and viridian lake
(Winsor Newton)—plus white
(M. Graham).
Below is another way to set up the charts using hexagons to represent the color wheel, with tints in the center. These are done with oil.
The colors you choose for your limited palette don’t have to be blue, red, and yellow, or even cyan, magenta, and yellow. As long as they’re differentiated, the painting will seem to have a full universe of colors.
Before you start a given painting, you can refer to a set of charts like these to decide which limited palette would suit the subject you want to paint. These charts would be a big help if you're thinking of joining in with the
Graveyard Painting Challenge for October.
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