A Theory of Colored Edges

Robert Henri "Portrait of Pat"
Robert Henri “Portrait of Pat”

Scientific phenomena always intrigues the artist especially if that phenomena centers around optics. In a sense it is as Plato inferred that art achieves its effect through illusion. I have always been curious about the theories of Michel-Eugene Chevreul. His study of optics and the effect of contrasting colors directly applies to painting and can be used, when understood properly, to heighten the sense of color in one’s work. Practically all artists are familiar with his theory of Simultaneous Contrast of Colors– when two compliments are side by side divided by a small strip of white, the colors tend to heighten one another, but if they are directly next to each other, the compliment of each appears in the other and there is a slight neutralization that takes place and therefore the colors are somewhat dulled. He also observes that if one stares to long at an object one is painting, the compliment of that object appears on the retina of the artist’s eye and remains there for a period of time and if fact, dulls his ability to see his subject as it actually appears before him. Therefore it is important for the artist to periodically rest his eye from the subject so that he may see it more clearly.

These theories are more or less common knowledge, although we constantly have to remind ourselves in regard to them. But his most interesting theory on which much can be inferred is his theory of colored edges. Let us say we have a red object next to a blue object or background. The red object as it approaches the blue object will appear to shift toward the orange because it is the compliment of the blue and simultaneously the blue object will shift toward the green as it approaches the red because it is the compliment of the red. So this passage would progress as such- R-RO-O-G-GB-B. The point of transition between the red object and the blue object or background would be- O-G. I find this incredibly useful in painting to achieve a heightened sense of color but also a smooth transition between objects and between an object and its background. In regard to the figure, it is especially useful in transitioning a half-tone edge into the background without over blending (the most typical way to deal with this type of passage).

This same idea is useful when painting a halo effect- when the edge of the figure is luminous because it faces directly into the light source. Adding color to this area greatly enhances the sense of brilliance of the flesh-using the shifting sense of the opposing compliments.

In contrast, some simple effects along edges can be had by just using a neutral. On The Juxtaposition of Colored and Grey Substances, Chevreul states that if the grey (or neutral) is selected properly in regard to tone,  it will exhibit the phenomena of contrast of color in a striking manner-achieving effective results and a heightened sense of color with minimum means. As I wrote in previous blog post, this is especially useful in those illusive and mysterious transitional passages along the shadow edge, but also, can be effective along a luminous edge.

This same idea can be used effectively to design an entire composition and is one Robert Henri used repeatedly. An intense color will transfer its compliment to more  subdued areas in a painting. That is why it is important to carefully select one or possibly two colors that will remain in their true state because their compliment will take up residence in the more tonal or neutralized areas- a transference of  complimentary colors unexpectedly adding intensity to an area. This will occur in the eye of the viewer as he stands before the work and should be taken into account and taken advantage of.  Henri believed there was much to this.

While Chevreul’s theories are dense, these are some practical applications I have found.