The energy emitted by a light source strikes matter/bodies, where it is partially absorbed. The remaining energy is reflected and reaches the eye, where it is projected onto the retina. The stimulus is then transmitted, by way of visual nerves, to the brain. This is where actual colour perception takes place. Whenever light from a natural or an artificial source is reflected by an object or dust particle, colour perception occurs. Depending on the composition of this object, the incoming light is either absorbed or reflected. In other words, parts of the spectrum of visible light are filtered out, while others reach our eyes in the form of colour stimuli.

The spectral composition of a colour stimulus changes according to the spectral composition of the light striking the object in question. For example, if white light falls on a blue surface, all spectral parts of this light are absorbed - except for the blue parts, which are reflected. That means that the colouration of an object is dependent on the type of light falling on it, such as natural daylight or various kinds of artificial light. Colours change by virtue of different qualities of light. The sensation of colour occurs more in three-dimensional space, rather than on surfaces. Only in three-dimensional space is colour really developed, gaining in tonal differentiation by virtue of ambient lighting.