The Nature of Colours

Although the world appears colorful to us humans, we must still admit that chromatic symphonies are nothing more than sensations. According to the laws of physics, the world is colorless and only a part of living things and we humans see it colored. Color is, therefore, a sensation and not an objective phenomenon, independent of man, as it does not have its own existence, not being a property of things such as pigmentation. Thus, when we talk about a colored object, we must take into account three distinct notions:

• rays of light;
• the surface of the object;
• our eye.

We can thus conclude – color is a subjective reality generated by the three factors listed above .

When we talk about colors, at first glance it seems that we all speak the same language, but in reality, the colors around us can be of two kinds, light (spectral colors ) or pigments (pigmentary colors ). Each group has different basic colors, and the resulting mixture differs for each group.

1. Pigment colors are those used by painters, prepared from pigments. The fundamental primary colors are the well-known ones: red, yellow and blue , and the secondary colors, derived from the first ones: orange, green and violet . The complementary pairs are: red-green, yellow-violet, orange-blue

The color wheel of pigment colors

Pigment color mixtures are known to the painter primarily from palette practice. They can be of two types:

- an optical (or additive ) one, where juxtaposed colors are perceived at the level of the retina. Such mixtures are found in works such as mosaics, pointillist painting, colored raster in old typography, etc.

Print Master Detail 6th century pavement mosaic George Serat Great Palace of Constantinople Study for “Le Chahut” 1889-1890 Courtauld Gallery, London

- the other physical (or subtractive) produced by the mixing of pigments before the colored rays reach the retina. The physical mixture can be done either by mixing colors or by superimposing transparent or semi-transparent glazes.

Physical mixture by superposition

Physical mixture – pigment melange (formation of shades)

2. Spectral colors are colored lights or light-colors. We observe changes in substance and name in them. The primary colors are here: vermillion red , yellowish green and blue-violet (ultramarine ), and the secondary colors, which result from the first, are: yellow, blue-green ( cyan or turquoise ) and magenta violet (better known as purple or cyclamen ). The complementary pairs in this case are: vermillion red with blue-green (cyan ), yellowish green with magenta violet (purple ), yellow with violet blue.

The mixing of spectral colors can also be done in two ways: by addition and subtraction.

The first of them, the addition one , is performed directly on the retina, and is also called optical . If the three primary colors are superimposed, white light is recomposed. The same thing happens if the three colors are just juxtaposed and viewed from a distance, adding up on the retina, creating the optical effect of white. This mixture can be seen best when three projectors are placed on colored bottles in the primary colors, and the mixture is done by projecting them onto a white screen.

The color wheel of spectral colors

Subtractive mixing occurs before the light rays reach the retina. And this mixing can best be demonstrated using a single projector on which all three colored bottles are mounted or stacked. Projecting them onto a white screen will produce the color black.

Additive mixing of spectral colors

We encounter such examples of mixtures in: color television ( additive mixing ), and subtractive mixing is found in various stage projections, colored light plays on water, etc.

Fernand Leger , a great creator, once said in the first half of the last century that: " never has the world been so colorful as today ", a statement that has remained valid to this day. Today we are bombarded by colors and sometimes even assaulted by them, we do not always know how to decode them and often react randomly.