Post -by Gautam Shah
Fresco (Italian =fresh), is a method of loading colours on a wet or green plaster. The term is mainly applied to art of creating paintings, but may include craft of painting the architectural entities like walls and ceilings. It was a slow and labourious process, but for many centuries, it was the only viable process for rendering a painting on a masonry surface and for applying architectural colour.
Fresco technique of coating was not suitable for wood, or other soft surfaces. Metals and alloys were new materials at that time, and being mostly non ferrous did not require any additional finish.
In TRUE OR REAL FRESCO, the colourant pigments are applied on the top layer of a multi layered plaster system. For structural and levelling purposes one or more layers of plaster were applied. The final layer was thinner, and this was scratched to imprint the outline or sketch of the scheme. The sketch was drawn directly or imprinted by using a full size replica drawn on cloth (and later paper), called a cartoon. The cartoons were often reused in different works of art. The outlines of the various figures and forms were than filled-in with indicative dark water-based colours. A topping or finishing plaster was laid over the drawing in small sections, and each section of wet plaster was loaded with final colour scheme. As the plaster dried, the lime in the plaster absorbed the carbon dioxide from the air, forming a surface of calcium carbonate. This film of calcium carbonate impregnated with the colours became part of the plaster mass.
The colours of a fresco are usually thin, translucent, and light, often with a chalky or pastel look. It was not possible to achieve saturated hues due to dominant presence of white of Lime.
It was very necessary to finish the section of the painting before the plaster set. Most of the paintings, as a result lacked the finer detailing and perforce consisted of bare essentials. As the work was carried out in zones, segment by segment, it became the ‘style of painting’. In early works of Fresco painting such compartmentalization is very apparent. In later art works paintings were overdrawn to create graduated or tonal variations. Defective portions were removed by scratching the plaster and redone, and patchy effects were inevitable.
The artist had to be well aware as to the amount of colour the plaster will hold or absorb. Too much pigment caused the surface to become chalky or powdery.
In later day Frescos, the fixing of colour was controlled with use of variety of fixers such as sizing compounds, starch, gums, and plant excreted resins. These fixers were mostly hygroscopic, and so used to ‘run’ in wet weather or developed fungus. Plant resins had a few other problems that such fixers on drying provided comparatively a flat or dull-matt finish. Plant resins were acidic in nature and not always suitable for alkaline masonry surfaces.
Fresco painting was known to the ancient Egyptians, Cretans, and Greeks. The Romans also practised fresco painting, examples of which are found in Herculaneum and Pompeii. In early Christian times (2nd C AD) Frescos were used to decorate the walls of catacombs, or underground burial chambers.
The art of fresco underwent a great revival in Italy during the 13th and 14th C., begun by the Florentine painters Cimabue and Giotto, who painted numerous fine works in churches in Assisi, Florence, and Pisa. In the 15th C. the art flourished in Florence, notably in the work of Masaccio, Benozzo Gozzoli, and Ghirlandaio. Fresco painting reached its peak in the 16th C., with the supreme achievements of Raphael in the Vatican Palace and with The Last Judgement and Genesis frescoes by Michelangelo in the Vatican’s Sistine Chapel. Fresco painting was widely practiced in Europe in the 18th C., with nobility of style replaced by elegance and illusionist effects. One outstanding fresco painter in this period was Giovanni Battista Tiepolo in Italy.
In FRESCO SECCO or lime-painting, the dry plaster was rubbed with a pumice stone to remove the crust, then washed with a thin mixture of water and lime. The colours were applied to this surface. Secco colours dry out lighter than their tone at the time of application, producing a pale, mat, chalky or ‘a distempered wall’ like effect. The fresco secco is inferior to true fresco. The colours are not clear, and the painting is less durable. The pigments are fused with the surface, but not completely absorbed in it, and may flake in time. Secco painting was the prevailing medium during medieval and early Renaissance period, and was revived in 18th C. Europe.
Sgraffito (Italian Graffiare, “to scratch”) is a form of fresco painting for exterior walls. A rough plaster undercoat is covered by thin layers of plaster, each stained with a different lime-fast colour. These coats were than covered by a fine-grain mortar finishing surface. The plaster was then engraved with sharp tools to varying depths to reveal the underlying layers of various colours. The surface of modern sgraffito fresco is often enriched with textures and with mosaics of stone, glass, plastic, and metal tesserae. Sgraffito has been a traditional folk art in Europe since the Middle Ages and was practiced as a fine art in 13th-century Germany. It has been recently revived in northern Europe.