Many of the works of art featured on this site are created using oil on canvas or panel, but they vary significantly in their finished appearance because of the different techniques used to create them. For example, look at Rembrandt’s portrait Titus. Rembrandt first blocked in the composition in broad brush strokes, then built up paint layers, working from dark to light. The heavy use of impasto (areas of thickly-applied paint) lends the image a feeling of spontaneity and immediacy. In some areas the rough textures look as if they have been applied with a palette knife rather than a brush, while some of the fine lines of the hair have been etched into the paint by the artist’s brush-handle.

Rembrandt’s bravura handling of paint on canvas was equalled only by Frans Hals in 17th-century Dutch art. In The Laughing Cavalier the vivid colours, differing textures and details of the costume are brilliantly captured by Hals’ fluid brushwork. The face is quite carefully executed in fine brushstrokes that blend together to illusionistic effect while the layers of lace in the ruff are conveyed by the build up of layers of opaque white paint. The more translucent cuff is quite a thin wash of white with opaque strokes depicting details. Strokes of black and grey are then used to convey the sheer of the silk satin sash. It is as though Hals is creating an essay in paint and showing off his various techniques. In other paintings, artists use ‘dry’ white paint on the surface to evoke lace or the shimmer of light on silk, for example those of Queen Charlotte, The Byam Family and Cardinal Pietro Ottoboni.

The technique used on the portrait of Admiral Lord Exmouth is a much more naïve style and is almost childlike in appearance. ‘Folk art’ typically uses flattened perspective and the inclusion of objects out of scale with each other. Pictures such as this tended not to be painted by professional artists but by untrained people who painted for fun or who had a particular story to tell.

Colour can be used specifically to structure a painting: look at the relationship between the blue of the dress and the sky in The Byam Family or the feather, the bow and trimming in Madame Perregaux. Colour can also be used symbolically. For example, red symbolises the position of Cardinal in the portrait of Cardinal Pietro Ottoboni and Pauline Bonaparte’s white dress could symbolise simplicity and purity. Many artists use a limited palette, for example in the portraits Titus and Pauline Bonaparte, which can add considerably to the force of the portrait. The use of colour here focuses our attention on particular aspects, such as a feeling of intimacy or an attempt to unravel the character of a person. Other artists use a range of colours to convey luxury and opulence.