Τρίτη, 22 Απριλίου 2014
Saving the Villa of the Mysteries [3st part] - Η διάσωση της Βίλλα των Μυστηρίων [μέρος 3ον]
Some of the methods currently being employed have been used by decades of conservators at Pompeii. Individual tesserae have been replaced, one by one, in each mosaic, using ancient tiles whenever possible. Frescoes have been cleaned by hand using a scalpel or a chemical solution. Painted surfaces have been consolidated with an acrylic resin diluted with deionized water and then injected into cracks. However, the teams today also have more high-tech tools at their disposal, including lasers to clean the frescoes, and ultrasound, thermal imaging, and radar to evaluate the level of decay of the walls and paintings. And drones are being used to examine the entirety of the villa’s protective covering. “The preciousness and historical importance of the Villa of the Mysteries necessitates great care,” says Vanacore. “I’m aware that we are working in one of Pompeii’s most important houses, and that our responsibility is enormous. I know that the work will forever be judged by the results, by people, and by time.”
Although frescoes appear to exist as a single layer on a wall, they are actually created in multiple layers in a way that makes the artwork part of the wall itself. True fresco is made by beginning with several coats of plaster—usually two rough coats that are allowed to dry and harden, and a third, smooth one. Dry pigments mixed with water are painted on while the third coat is still wet. As this uppermost layer dries, the painting becomes part of the wall, creating a durable surface that can last for hundreds, indeed thousands, of years, unlike an oil painting on canvas, for example, which can easily peel or chip. The Villa of the Mysteries has dozens of frescoed walls, almost all of which need attention, according to Vanacore.
Though these walls are durable, they still must be handled carefully. “We felt that lasers were a good method to clean the frescoes because they allow for the gentle cleaning of hard surfaces, and there is minimal impact on the work of art,” says Vanacore. Although lasers are generally used for cleaning stone, they have been tested on metals and pottery as well to great success. The process by which the lasers clean the frescoes—a few microns at a time—is called photoablation, a sort of vaporization of what can appear as a layer of black crust. “This allows for precise cleaning of very delicate surfaces, and it’s also much less time consuming than using a scalpel or chemicals,” Vanacore adds. Even where the surface is very degraded, lasers can remove minuscule amounts of dirt without affecting the layer underneath, revealing as much of the ancient painting as possible without putting it at risk.
πηγή : http://www.archaeology.org/issues/124-1403/features/1813-pompeii-saving-the-villa-of-the-mysteries#art_page3