RYB color model
RYB (an abbreviation of red–yellow–blue) is a historical set of colors used in subtractive color mixing, and is one commonly used set of primary colors. It is primarily used in art and design education, particularly painting.
RYB (red–yellow–blue) make up the primary color triad in a standard artist's color wheel. The secondary colors purple–orange–green (sometimes called violet–orange–green) make up another triad. Triads are formed by three equidistant colors on a particular color wheel. Other common color wheels represent the light model (RGB) and the print model (CMYK).
The first known instance of the RYB triad can be found in the work of Franciscus Aguilonius (1567–1617) though he did not arrange the colors in a wheel.
In his experiments with light, Isaac Newton recognized that colors could be created by mixing color primaries. In his Opticks, Newton published a color wheel to show the geometric relationship between these primaries. This chart was later confused and understood to apply to pigments as well, though Newton was also unaware of the differences between additive and subtractive color mixing.
The RYB model was used for printing, by Jacob Christoph Le Blon, as early as 1725.
In the 18th century, the RYB primary colors became the foundation of theories of color vision, as the fundamental sensory qualities that are blended in the perception of all physical colors and equally in the physical mixture of pigments or dyes. These theories were enhanced by 18th-century investigations of a variety of purely psychological color effects, in particular the contrast between "complementary" or opposing hues that are produced by color afterimages and in the contrasting shadows in colored light. These ideas and many personal color observations were summarized in two founding documents in color theory: the Theory of Colors (1810) by the German poet and government minister Johann Wolfgang von Goethe, and The Law of Simultaneous Color Contrast (1839) by the French industrial chemist Michel-Eugène Chevreul.
Painters have long used more than three RYB primary colors in their palettes, and at one point considered red, yellow, blue and green to be the four primaries. Red, yellow, blue and green are still widely considered the four psychological primary colors, though red, yellow and blue are sometimes listed as the three psychological primaries, with black and white occasionally added as a fourth and fifth.
The cyan, magenta, and yellow primary colors associated with CMYK printing are sometimes known as "process blue", "process red" and "process yellow".
Starting from Goethe, it was increasingly understood that mixing of colored light in the eye is a process different from mixing of dyes.
- James Gurney (2010). Color and Light: A Guide for the Realist Painter. Andrews McMeel Publishing. p. 75. ISBN 978-0-7407-9771-2.
- "Franciscus Aguilonius". Colorsystem: Colour order systems in art and science. Archived from the original on 2014-02-13.
- MacEvoy, Bruce (April 19, 2009). "handprint : color wheels". Retrieved 2009-06-30.
- MacEvoy, Bruce (April 19, 2009). "handprint : do "primary" colors exist?". Retrieved 2009-06-30.
- For instance Leonardo da Vinci wrote of these four simple colors in his notebook circa 1500. See Rolf Kuenhi. “Development of the Idea of Simple Colors in the 16th and Early 17th Centuries”. Color Research and Application. Volume 32, Number 2, April 2007.
- Stroebel, Leslie D.; Current, Ira B. (2000). Basic Photographic Materials and Processes. Focal Press. ISBN 0-240-80345-0.
- Ross, MS Sharon; Kinkead, Elise (2004). Decorative Painting & Faux Finishes. Creative Homeowner. ISBN 1-58011-179-3.
- Swirnoff, Lois (2003). Dimensional Color. W. W. Norton & Company. ISBN 0-393-73102-2.