Johannes Itten’s color wheel is probably the best-known representation of primary and secondary colors. This shows which hues are created when the primary colors are tinted together in different ratios. This simple mixing variant, which we also know from the ink box, is called Additive Color Mixing.
Inside it, the color wheel consists of the three primary colors yellow, red (or magenta) and blue (or cyan). Primary colors are called primary colors because they cannot be mixed with other colors. Conversely, however, all other tones are produced from them.
If you mix two of the primary colors that are next to each other – you get the secondary colors. Blue with red becomes violet, yellow with blue becomes green, and red with yellow becomes orange. Secondary colors with an exact 50:50 ratio of the primary colors, are represented as wide triangles. The outer circle, on the other hand, represents the different gradations of the secondary colors, depending on whether they contain more or less portions of a primary color.
Tertiary colors are those mixed shades that result from the mixture of all three primary colors. It always results in gradations of brown, tones that occur particularly frequently in nature.
Johannes Itten assumed that colors influence each other. He summarized the systematics of the color wheel in seven color contrasts, according to which the theory of colors is still largely oriented today.
The simplest of all color contrasts is the color-aspect contrast, or simply color contrast. It is created when at least two colors stand next to each other in pure – not tinted – form. As in the inner triangle of the color circle itself, where red, yellow and blue shine next to each other in pure form. This contrast looks very colorful and loud. Expressionists and abstract painters, such as Franz Marc, Mondrian, and Wassily Kandinsky, were fond of this contrast.
Light-dark contrast, as the name implies, uses the lightness and darkness of a hue. This can be used to generate depth effects, because light areas optically recede and dark tones "approach" the viewer. Painters like Rembrandt or Goya are especially known for their light-dark contrasts.
Red, yellow and orange are called warm colors because we associate them with direct light sources. Bluish tones, on the other hand, seem rather cold. According to Johannes Itten, the cold colors are on the right and the warm colors on the left side of the color wheel. However, this can be contradicted, since green and violet can also be described as "neutral", because they each consist of one warm and one cold color. The cold-warm contrast is ideal in painting for depicting the depth effect of landscapes – landscapes "fade" towards the back. This also means that we perceive bluish colors as receding and reddish or yellowish colors as approaching.
Quality contrast or intensity contrast is the contrast between rich, bright color tones and dull, toned-down nuances. Similar to the light-dark contrast, a depth effect can be achieved by simply tinting the same color with white or gray. In painting, this achieves a kind of depth of field as in photography.
Colors have fundamentally different "luminosities. Goethe was the first to note this in the Theory of Colors and to establish clear measurement figures for it. An orange surface appears twice as intense as a blue surface of the same size. Red and green are in equilibrium, whereby one part yellow corresponds to about three parts violet. If you know how to use this contrast effect, the statics of a painting can be influenced and paintings have a calming to suspenseful effect.
Secondary colors that are directly opposite each other in the color wheel are called complementary colors. Directly next to each other, they produce the so-called complementary contrast – one of the strongest color contrasts. Complementary contrasts are combinations of yellow and violet, red and green, and blue and orange. If two complementary colors are mixed together, the result is always a gray tone, in contrast to other color mixtures.
Simultaneous and successive contrast
Color contrasts such as simultaneous contrast or successive contrast are often used for optical illusions. When looking at a complementary color, the human sense of sight is designed to always look for the "counterpart" in order to experience a "color whole". Successive contrast occurs when, while looking at a color, the opposite image of it gradually appears on the retina. The test is very simple: fix the negative of a photo for a few minutes and then quickly direct your gaze to a white surface. What the sense of sight then presents to us – the illusion of the photo – is called successive contrast. Simultaneous contrast works on a similar principle, but plays with the simultaneous interaction of adjacent color areas. If you look at a surface that consists of tiny colored dots, for example, you get a sensory overload that the brain tries to compensate for. In this case, the eye does not perceive all colors, but only nuances of certain tones – nevertheless, such a surface seems to vibrate or literally swarm. Pointilism and Impressionism, for example, make use of this principle.