In The Painter’s Palette, Denman Ross presents various palettes that explore a limitation of color in the set-palette. These set-palettes, although limited in color to a series of complements, investigate color temperature in the most thorough manner. His basic premise relies on looking at the full spectrum palette in terms of the chroma/ value relationship. Yellow is the lightest color in the spectrum, therefore when one looks at the full spectrum, one can observe that there is a movement up to light from two directions. A movement from red through orange up to yellow. And another movement from violet through blue and green up to yellow. Violet-red, which is lighter in value than violet, acts as a transition back to the red movement up to yellow. One can observe not only a value increase toward yellow, but also a temperature variance. The movement through red to yellow is a warm movement and the movement through blue and green a cool movement.
Ross’ theory is that these two movements of temperature up to yellow (which also includes value, each color in its pure state getting lighter as it approaches the yellow) act in a counter motion to one another (see DR IV HC below, from The Painter’s Palette, Denman Ross, 1919, p.30), so that in this movement, the complements of each color align in such a way as to allow the mixing of neutrals between the complements. This design of the palette is quite ingenious because it compresses value, color temperature and complements into a working system. The artist, in short order, can mix the appropriate value, color temperature and neutrality necessary for the situation.
There are rules to follow in the mixing process. One needs to keep the mixes distinct, not to over-mix areas of the palette. Secondly, one ideally needs to mix on a diagonal. Mixing on a diagonal means mixing, not two colors of the same value, but mixing one of lower value with a higher value. This is tricky to maintain in a painting situation. Thirdly, one should ideally mix a cool color with a warm color to achieve a temperature balance. So I should lighten say, GB, which is a cool, with a warm, either a yellow lightener or a RO of lighter value. RO being the complement to GB, I will achieve some neutrality in the mix (By mixing certain proportions of each color to achieve the color and neutrality that I desire).
So, these palettes are built on complements as well as lighteners. These lighteners appear in two temperatures a warm, usually a yellow+white, and a cool, usually a violet+white. These lighteners are a substitute for white, therefore there is no pure white on the palette. These two color temperatures identify the light source I am working under. Is it a cool light (violet)or is it a warm light (yellow)? One can use any cool or warm color as a lightener, but Ross tends to use these two in his most versatile palettes.
Robert Henri experimented extensively with Ross’ set-palettes and felt there was a great deal to learn from Ross’ discoveries. Henri spent the most arduous experimentation on the palette, DR IV HC. This is the Denman Ross, #4 palette , that has a movement that is hot and a movement that is cold. Henri liked this palette because the color was strong and produced a feeling of a “corner of light”. There is a wide range of darks in the lower palette and a varied rage of lights in the upper palette. Henri found the triad of H4 and C3 to be the most useful for flesh tones and on several experiments concentrated heavily in this area of the palette.
Here are some results from my own personal investigations. These studies are of the H4, C3, H2 and C1 triads. A triad is created by looking at the vertices of each triangle. Each triad is identified as a warm or cool movement. Also, the values indicated on the left of the diagram are highlight, middle value and low dark. Both RO and the GB fall in the middle value scale (according to Ross’ color/value chart in On Drawing and Painting, 1912, p.42 insert, both GB and RO fall in middle value in their unadulterated state) and the violet and the yellow appear as both highlight and low dark. Because of the two scales of value that yellow and violet occupy, they will not be exactly the same color combination. I have taken my mixes from Robert Henri’s notebook of October, 1919.
(The video above mixes solely the H4 triad.)
Please feel free to use the comments below ask any questions you might have.