A closer look at watercolour technique
Conservation record photograph: detail in raking light, Arthur Streeton Egyptian vendor of drinks 1897 (detail) watercolour and pencil on paper Collection of the National Gallery of Australia more detail
The works on paper in Moist: Australian watercolours cover a wide range of periods and genres, but the one aspect they have in common is the medium of watercolour. In the purest sense watercolour is a painting medium which uses pigments dispersed in water and bound in gum, applied by brush to a paper support. This basic principle has remained unchanged over 500 years. The gum is customarily gum arabic mixed as a proprietary formula with other ingredients to enhance its working characteristics. The pigments would once have been extracted from minerals and plants, ground by hand and stored in shells. More familiar colours pre-prepared in pans or tubes, kept moist and easy to work with the addition of humectants and wetting agents such as honey and ox gall, were developed in the nineteenth century. Modern pigments are likely to have a synthetic origin and are usually machine-ground to ensure a homogenous composition.
The conventional support for watercolour is paper, held flat and taut; preferably with a textured surface and the right degree of absorption to allow for a controlled application of the thin, fluid wash. A rough finished paper is often preferred as the tiny hollows in the surface impart vitality and variety to the wash. The choice of paper colour is almost always white or cream as the lightness of the paper is reflected through the sheer layer of applied colour, providing the desired brilliance in the pigments
Watercolour reached its peak of technical excellence as an artform in England between the eighteenth and the nineteenth centuries, becoming both a collectable and exhibitable commodity. Initially it was regarded as a medium for amateurs. Many artists supplemented their income by teaching and writing manuals for watercolour painting. The current abundance of modern manuals attests to the technique’s enduring popularity and accessibility. Historically, the purpose of the work played an important role in the choice of materials and technique. In the nineteenth century, the creation of a highly finished watercolour intended for public display or sale would have been approached in a quite different manner to that of a work produced for private consumption.
Watercolour was originally used simply as a means of tinting prints and drawings, since its transparency allows the underlying structure of the ink or pencil lines to remain visible. A large expressive range is possible as the colour itself can be layered or blended in a number of ways. In Rah Fizelle’s figure studies the pigment washes have been impressively handled, using a wet-on-wet technique over the soft pencil outlines. The granular nature of the pigments is apparent, particularly in the bands of red and brown ochres, which have been applied adjacent to one another, allowed to combine and yet remain distinct.
Watercolour washes are dispersions of solid particles in water, not dyed water; the smaller the particles, the longer they will remain in suspension. Organic pigments, such as indigo and madder, are made up of extremely small particles, so the resulting paints are easier to handle compared with those which have a more granular texture like ochres. Blues have notoriously varied handling properties. Prussian blue and indigo wash easily and evenly, whereas other blues such as cobalt and ultramarine deposit grainy sediments.
Conservation record photograph: before treatment. The disfiguring brown spot stains in the upper right quadrant of the image are known as ‘foxing’. Rah Fizelle Study of a woman 1938–39 (detail) watercolour and pencil on paper, Collection of the National Gallery of Australia more detail
Many artists avoid pre-mixing watercolour pigments on a palette as this can deaden the colour. Instead, the purity of the pigment can be maintained by building up layers of transparent washes. The technique can appear deceptively simple, but it requires virtuoso handling. By this means it is possible to capture those sought-after fleeting impressions of atmosphere and light. The layered wash in Streeton’s Egyptian vendor of drinks 1897 is notable for its transparency, which even in the shadow areas creates an extraordinary depth and luminosity. There are barely any indications of drawing. Expanses of white paper, unmodulated except for a few touches of wash, define the pillars of the white arch from which the figure is emerging into the harsh brilliance of an exotic sunlight.
Whites are one of the greatest causes of controversy. Purists argue that highlights should only be created through the reserved white of the paper or the smallest touches of body colour. Gouache is a medium in which the transparent watercolour pigments are provided with opacity by the admixture of white. The addition of chalk, fillers and extenders reduces the amount of pigment used, making gouache a more economical option.
In Streeton’s work the only added white highlights are those indicating the birds in the background. Highlights could also be achieved by a plethora of reductive techniques including scratching, sponging and even sandpapering so that selected areas of wash would be removed revealing the white paper beneath. The English papermakers Whatman became famous for their papers in the eighteenth and nineteenth centuries; not only because of their wove structure and range of textured finishes, but because of their unique hard, gelatine-sized surfaces which could withstand the rigours of reductive watercolour techniques without disintegrating into pulp.
Although extraordinary vibrancy can be achieved with watercolour, light exposure may diminish pigment intensity and darken paper supports, destroying the tonal contrast. When a work has faded the margin areas of paper under the window mount provide a vital record of the original appearance. Such a change is apparent in William Westall’s small seascape Cape Wilberforce, where a traditional wash technique has been employed. Indian red, a light stable pigment, has been applied in the sky area. This is now apparent as pink clouds; while a yellowish-brown ochre is visible in the sea. Originally, a wash of indigo would have been laid over both, with the underlying warm and cool tones, providing the differentiation between sky and sea. The indigo wash has faded completely. Only small patches of a bright, light stable blue remain in the sky. Pigments such as indigo are exceptionally fugitive (light sensitive) but have continued to be favoured by artists.
Conservation record photograph: the unfaded blue pigment in the margin area is visible on the left edge. William Westall Cape Wilberforce 1802 watercolour, pencil and gum arabic on paper Collection of the National Gallery of Australia more detail
With the exception of miniature portraits, watercolours were originally kept in albums, which assisted in their care and preservation. When the Royal Academy was established in 1780 a small room was included for the display of watercolours, acknowledging the medium’s ascendance, although not its equality with oils.
Mounting and framing created new problems. Constant exposure to light and polluted air damaged pigments and degraded paper; poor quality, acidic mounting materials compounded the problems. Artists resorted to varnishing and glazing works in an attempt to keep them safe. In the nineteenth century many new and exotic pigments became available. Unfortunately many were unstable, particularly the aniline dyestuffs. The permanence of watercolours was the subject of much controversy and debate.
Public concern led eventually in 1835 to the publication of George Field’s Chromatography, the first truly scientific investigation into artists’ pigments, and later in 1888 to a government enquiry. The Russell and Abney Report on The Action of Light on Watercolours had far-reaching effects and established the principles on which modern gallery conservation and display standards are based.
Senior Paper Conservator