Coloured afterimagesIf a person stares for about 30 seconds at the coloured disk under a clear light and then fixes upon the empty space of the adjacent circle, coloured afterimages will appear. Encyclopædia Britannica, Inc.
Hues containing a high proportion of blue (the violet to green range) appear cooler than those with a high content of yellow or red (the green-yellow to red-violet range). This difference in the temperature of hues in a particular painting is, of course, relative to the range and juxtaposition of colours in the design. A green will appear cool if surrounded by intense yellow, while it will seem warm against blue-green. The optical tendency for warm colours to advance before cold had been long exploited by European and Asian painters as a method of suggesting spatial depth. Changes in temperature and intensity can be observed in the atmospheric effects of nature, where the colours of distant forms become cooler, grayer, and bluish, while foreground planes and features appear more intense and usually warmer in colour.
Optical colour change(Top) By complementary action, the same gray pigment will appear greenish when adjacent to red but reddish if adjacent to green. (Bottom) A green hue will seem cool if surrounded by yellow but warm when surrounded by blue-green.Encyclopædia Britannica, Inc.
The apparent changes in a hue as it passes through zones of different colour has enabled painters in many periods to create the illusion of having employed a wide range of pigment hues with, in fact, the use of very few. And, although painters had applied many of the optical principles of colour behaviour intuitively in the past, the publication of research findings by Chevreul and others stimulated the Neo-Impressionists and Post-Impressionists and the later Orphist and Op art painters to extend systematically the expressive possibilities of these principles in order to create illusions of volume and space and vibrating sensations of light and movement. Paul Cézanne, for example, demonstrated that subtle changes in the surface of a form and in its spatial relationship to others could be expressed primarily in facets of colour, modulated by varying degrees of tone, intensity, and temperature and by the introduction of complementary colour accents.
While the often complex religious and cultural colour symbologies may be understood by very few, the emotional response to certain colour combinations appears to be almost universal. Optical harmonies and discords seem to affect everyone in the same way, if in varying degrees. Thus, an image repeated in different schemes of colour will express a different mood in each change.
Emotive colour relationshipsAn identical pattern of shapes may express a different emotional mood through each colour variation. Encyclopædia Britannica, Inc.
Texture
Pointillism (a term given to the Neo-Impressionist system of representing the shimmer of atmospheric light with spots of coloured pigment) produced an overall granular texture. As an element of design, texture includes all areas of a painting enriched or animated by vibrating patterns of lines, shapes, tones, and colours, in addition to the tactile textures created by the plastic qualities of certain mediums. Decorative textures may be of geometrical repeat patterns, as in much of Indian, Islamic, and medieval European painting and other art, or of representations of patterns in nature, such as scattered leaves, falling snow, and flights of birds. Volume and space
The perceptual and conceptual methods of representing volume and space on the flat surface of a painting are related to the two levels of understanding spatial relationships in everyday life.
Perceptual space is the view of things at a particular time and from a fixed position. This is the stationary window view recorded by the camera and represented in the later periods of ancient Greek and Roman paintings and in most Western schools of painting since the Renaissance. Illusions of perceptual space are generally created by use of the linear perspectival system, based on the observations that objects appear to the eye to shrink and parallel lines and planes to converge as they approach the horizon, or viewer’s eye level.
Young children and untrained artists, however, do not understand space in this way and represent it conceptually. Their paintings, therefore, show objects and surroundings independently of one another and from the views that best present their most characteristic features. The notion of scale in their pictures is also subjective, the relative size of things being decided by the artist either by their degree of emotional significance for him or by their narrative importance in the picture (interest perspective).
The conceptual, polydimensional representation of space has been used at some period in most cultures. In much of ancient Egyptian and Cretan painting, for example, the head and legs of a figure were shown in profile, but the eye and torso were drawn frontally. And in Indian, Islamic, and pre-Renaissance European painting, vertical forms and surfaces were represented by their most informative elevation view (as if seen from ground level), while the horizontal planes on which they stood were shown in isometric plan (as if viewed from above). This system produces the overall effect that objects and their surroundings have been compressed within a shallow space behind the picture plane.
By the end of the 19th century Cézanne had flattened the conventional Renaissance picture space, tilting horizontal planes so that they appeared to push vertical forms and surfaces forward from the picture plane and toward the spectator. This illusion of the picture surface as an integrated structure in projecting low relief was developed further in the early 20th century by the Cubists. The conceptual, rotary perspective of a Cubist painting shows not only the components of things from different viewpoints but presents every plane of an object and its immediate surroundings simultaneously. This gives the composite impression of things in space that is gained by having examined their surfaces and construction from every angle.
In modern painting, both conceptual and perceptual methods of representing space are often combined. And, where the orbital movement of forms—which has been a basic element in European design since the Renaissance—was intended to hold the spectator’s attention within the frame, the expanding picture space in late 20th- and early 21st-century mural-size abstract paintings directs the eye outward to the surrounding wall, and their shapes and colours seem about to invade the observer’s own territory.
Opening out the picture spaceThe movement of shapes in Morris Louis's acrylic painting Alpha-Phi, 1961, directs the spectator's eye outside the picture surface. In the Tate Gallery, London. 2.59 × 4.58 metres. In contrast, Vermeer's design is contrived to hold the spectator's attention within the frame.Courtesy of the trustees of the Tate, London; photograph, A.C. Cooper Ltd.
Time and movement
Time and movement in painting are not restricted to representations of physical energy, but they are elements of all design. Part of the viewer’s full experience of a great painting is to allow the arrangement of lines, shapes, and accents of tone or colour to guide the eye across the picture surface at controlled tempos and rhythmic directions. These arrangements contribute overall to the expression of a particular mood, vision, and idea.
Centuries before cinematography, painters attempted to produce kinetic sensations on a flat surface. A mural of 2000 bce in an Egyptian tomb at Beni Hasan, for instance, is designed as a continuous strip sequence of wrestling holds and throws, so accurately articulated and notated that it might be photographed as an animated film cartoon. The gradual unrolling of a 12th-century Japanese hand scroll produces the visual sensation of a helicopter flight along a river valley, while the experience of walking to the end of a long, processional Renaissance mural by Andrea Mantegna or Benozzo Gozzoli is similar to that of having witnessed a passing pageant as a standing spectator.