The Numerical Values of Color (Goethe's Theory)
As a portrait photographer, the thought of creating a balanced composition with your subject, pose, and background is no easy task. Once you factor in the added layer of color, achieving balance in an image is even more tricky. If only there were some kind of system that could be used to determine how much color to use in a composition to each balance…
Enter Goethe. Johann Wolfgang von Goethe was a scientist (among many other things) who was immensely involved in color theory. He took it on himself to devise a system for creating harmonious color schemes. He ascribed numerical values to colors, with brighter colors (like yellow) getting a higher value, and darker colors (like purple) getting a lower value. Here are the values he came up with:
Red – 6
Orange – 8
Yellow – 9
Green – 6
Blue – 4
Violet – 3
Thus, in order to achieve balance in a composition of purple (3) and yellow (9), the ratio would need to be three parts purple to one part yellow. Orange and blue are less intense colors, so balance is achieved at a 2:1 ratio of orange to blue. Red and green represent equal values.
In photographic terms, the numerical values at work will be determined not only be light placement, but also by the framing of each composition. The final image will need to have the appropriate proportions, independent of how balanced the light outputs were.
To demonstrate Goethe’s theory, I brought in my friend (and singer of Saintseneca) Zac Little to sit for three different setups. In the first scenario, I wanted to demonstrate the red-green relationship. I lit him with green-gelled and red-gelled lights, each fired through soft boxes on either side of him. The green-gelled light needed twice the output as the red, based on the density of the gel I was using.
Interesting fact: when you mix green and red light, you get yellow light, hence the background color. It looks more orange in this case because I pushed the file more warm in post. When you are color grading a file that consists of a wide range of warm and cool tones, you can dramatically change the look of an image with even the slightest tweak of the white balance— you’ll see entire colors emerge or disappear completely.
For the second setup I had the blue-gelled light in a more frontal position, with the orange light acting as an accent on the left. Because the main light was especially front-facing, it was not only lighting Zac but also the background, resulting in a blue-heavy image. To closer to the 1:2 ratio, I added an orange background light (placed under the stool). The blue-gelled light needed to be four times brighter than the orange light, due to differences in density.
For the purple-yellow relationship, I wanted to create a shape with the yellow. The purple light was diffused through a soft box, and placed front and center in order to fill the frame with soft, purple light. For the yellow, I used two flashes, mounted on a triple-flash bracket, and modified with DIY barn-door snoots. The barn-door snoot contains the light to a thin line of light, so by positioning one in a horizontal position and one in a vertical, where they overlap, a “+” or an “x” is created. The purple-gelled light needed to be 16-times brighter than the yellow, due to differences in density.
It should go without saying, but when it comes to art, there are no actual rules— merely guidelines that lead us toward more aesthetically pleasing results. I for one am I fan of a good guideline to help illuminate my artistic path, so i thoroughly enjoyed putting Goethe’s theory to the test.
If you found this study interesting, you may enjoy my new book, Chroma: A Photographer’s Guide to Lighting with Color, which is a deep dive into the photographic world of color.