Shape and mass, as elements of design, include all areas of different colour, tone, and texture, as well as individual and grouped images.
Children instinctively represent the things they see by geometrical symbols. Not only have sophisticated modern artists, such as Paul Klee and Jean Dubuffet, borrowed this untutored imagery, but the more arresting and expressive shapes and masses in most styles of painting and those to which most people intuitively respond will generally be found to have been clearly based on such archetypal forms. A square or a circle will tend to dominate a design and will therefore often be found at its focal centre—the square window framing Christ in Leonardo da Vinci’s Last Supper, for example, the hovering “sun” in an Adolph Gottlieb abstract, or the halo encircling a Christian or Buddhist deity. A firmly based triangular image or group of shapes seems reassuring, even uplifting, while the precarious balance implied by an inverted triangular shape or mass produces feelings of tension. Oval, lozenge, and rectangular forms suggest stability and protection and often surround vulnerable figures in narrative paintings.
There is generally a cellular unity, or “family likeness,” between the shapes and masses in a design similar to the visual harmony of all units to the whole observed in natural forms—the gills, fins, and scales in character with the overall shape of a fish, for example.
The negative spaces between shapes and masses are also carefully considered by the artist, since they can be so adjusted as to enhance the action and character of the positive images. They can be as important to the design as time intervals in music or the voids of an architectural facade. Colour
In many styles and periods of painting, the functions of colour are primarily decorative and descriptive, often serving merely to reinforce the expression of an idea or subject communicated essentially in terms of line and tone. In much of modern painting, however, the full-spectrum range of pigments available has allowed colour to be the primary expressive element.
colourA variety of colourful paints.© adimas/Fotolia
The principal dimensions of colour in painting are the variables or attributes of hue, tone, and intensity. Red, yellow, and blue are the basic hues from which all others on the chromatic scale can be made by mixtures. These three opaque hues are the subtractive pigment primaries and should not be confused with the behaviour of the additive triads and mixtures of transparent, coloured light. Mixtures of primary pairs produce the secondary hues of orange, violet, and green. By increasing the amount of one primary in each of these mixtures, the tertiary colours of yellow-orange, orange-red, red-violet, violet-blue, blue-green, and green-yellow, respectively, are made. The primary colours, with their basic secondary and tertiary mixtures, can be usefully notated as the 12 segments of a circle. The secondary and tertiary colour segments between a pair of parent primaries can then be seen to share a harmonious family relationship with one another—the yellow-orange, orange, and orange-red hues that lie between yellow and red, for example.
Colour(Left) Colour wheel made up of the primary colours and their basic secondary and tertiary mixtures. (Right) Colour wheel with approximate, inherent tonal values.Encyclopædia Britannica, Inc.
Local hues are the inherent and associative colours of things. In everyday life, familiar things are described by particular colours, and these often are identified by reference to familiar things; the green of grass and the grass green of paint, for instance. Although, as the Impressionists demonstrated, the inherent colours of forms in the real world are usually changed by effects of light and atmosphere, many of the great “primitive” and classical styles of representational painting are expressed in terms of local hues.
Tone is a colour’s relative degree, or value, of lightness or darkness. The tonal pattern of a painting is shown in a monochrome reproduction. A painting dominated by dark colours, such as a Rembrandt, is in a low tonal key, while one painted in the pale range of a late Claude Monet is said to be high keyed. The tonal range of pigments is too narrow for the painter to be able to match the brightest lights and deepest darks of nature. Therefore, in order to express effects of illumination and dense shadow, he must lower the overall tonal key of his design, thus intensifying the brightness value of his lightest pigment colours.
The Greco-Roman, Renaissance, and Neoclassical method of representing volume and space in painting was by a system of notated tonal values, the direction of each plane in the design being indicated by a particular degree of lightness or darkness. Each tonal value was determined by the angle at which a plane was meant to appear to turn away from an imaginary source of light. The tonal modeling, or shading, of forms was often first completed in a monochrome underpainting. This was then coloured with transparent washes of local hues, a technique similar to that of colour tinting a black-and-white photograph.
An example of the early oil method of (left) colour glazing a (right) monochrome painting.
Each hue has an intrinsic tonal value in relation to others on the chromatic scale; orange is inherently lighter than red, for instance, and violet is darker than green. Any reversal of this natural tonal order creates a colour discord. An optical shock is therefore produced when orange is juxtaposed with pink (a lighter tone of red) or pale violet is placed against dark green. Such contrasts as these are deliberately created in paintings for the purpose of achieving these dramatic and disturbing effects.
The intensity of a colour is its degree of purity or hue saturation. The colour of a geranium, therefore, is said to be more intense, more highly saturated with pure orange-red than is mahogany. The pigment vermilion is orange-red at maximum intensity; the brown earth pigment burnt sienna is grayer and has a lower degree of orange-red saturation.
Intense hues are termed chromatic colours. The achromatic range is made up of hues reduced in intensity by the addition of white, making the tints, or pastel colours, such as cream and pink; or of black, producing the shades, or earth colours, such as mustard and moss green; or of both white and black, creating the neutralized hues, or colour-tinged grays, such as oatmeal and charcoal.
An achromatic colour will seem more intense if it is surrounded by neutralized hues or juxtaposed with its complementary colour. Complementaries are colour opposites. The complementary colour to one of the primary hues is the mixture of the other two; the complementary to red pigment, for example, is green—that is, blue mixed with yellow. The colour wheel shows that the tertiaries also have their colour opposites, the complementary to orange-red, for instance, being blue-green. Under clear light the complementary to any chroma, shade, or tint can be seen if one “fixates,” or stares at, one colour intently for a few seconds then looks at a neutral, preferably white, surface. The colour afterimage will appear to glow on the neutral surface. Mutual enhancement of colour intensity results from juxtaposing a complementary pair, red becoming more intensely red, for instance, and green more fiercely green when these are contiguous than either would appear if surrounded by harmonious hues. The 19th-century physicist Michel-Eugène Chevreul referred to this mutual exaltation of opposites as the law of simultaneous contrast. Chevreul’s second law, of successive contrast, referred to the optical sensation that a complementary colour halo appears gradually to surround an intense hue. This complementary glow is superimposed on surrounding weaker colours, a gray becoming greenish when juxtaposed with red, reddish in close relationship with green, yellowish against violet, and so on.