Sunday, April 29, 2007

Dog Drool on a DaVinci

Having just posted thoughts about restoration of paintings, I came across this tale of restoration woe in Artemisia, by Alexandra LaPierre, translated from the French by Liz Heron.

Background: By the 1620s, the Gonzaga dynasty in Mantua had declined from five consecutive generations of extremely refined art connoisseurship, combined with great wealth, to a series of disinterested Dukes who had no real interest in art and a desperate need for cash. The Spanish and French monarchs also coveted the Gonzaga collection, but it was the English King, Charles I, whose emissary carried away the hugely valuable art collection -- hundreds of antiquities, decorative artifacts and Renaissance paintings.

It was the celebrated collection of which Rubens had been curator for eight years, and it included, besides Caravaggio’s Death of the Virgin which is now in the Louvre, a Raphael Holy Family, Titian’s Entombment, and several dozen other paintings by the likes of Mantegna, Correggio, Giulio Romano and Leonardo da Vinci.

Having concluded the arduous, clandestine negotiations on behalf of his King, Nicholas Lanier packed the art works for transport to London. Knowing that the watercolors would not fare well on a sea voyage, he carried those with him on his overland journey. The rest was crated up and stowed aboard the Margaret –carefully segregated on one side of the hold, away from the sacks of grapes and barrels of mercury.

But Lanier hadn’t considered “the effects of heat and condensation on the sugar and the mercury in the hold.” Uncrating the artworks in England, Lanier discovered that the evaporating mercury had left a sticky layer of ink-colored quicksilver on the canvases, and had saturated the drawings.

A frenzied restoration effort ensued. Although Lanier was by now being castigated by the French and the Spanish (and by the Mantuan people who knew what they had lost) for having “stolen” the collection – having paid far below its market value – nonetheless a large hole had been made in the English Treasury to acquire these works. The King would not be pleased.

“But sponges soaked in milk or dog’s slaver – the customary methods – had not completely erased the ghastly overlay.” The most famous chemists in the realm suggested countless ineffective solutions. He swabbed the canvases with brandy. He dripped droplets of alcohol distilled from wine. Still a film remained. “Finally, he washed the finest canvases with plenty of water. Determination, luck and a mastery of the techniques of painting enabled him to restore some of the masterpieces. He enjoyed His Majesty’s favor more than ever.”

Imagine calling Fido over to drool on a DaVinci!

Thursday, April 26, 2007

Color Controversy in Art History

The controversy around the restoration of the Sistine Chapel ceiling in the 1990s has always struck me as odd. A surprisingly large cadre of critics objected to the brilliance of the colors when the restoration was unveiled, believing them to be too “modern”. I find this odd because it’s widely known that Mediaeval and Renaissance fortunes were made, intrigue and political manipulations abounded and, I suspect, murder was even done in pursuit of control of the components of brilliant colors.

For example, after the Ottomans gained control of and limited access to traditional sources of alum, the Papacy took aggressive steps to control new-found alum sources in Italy. One of the important uses for alum was as a color fixative in dyes and paints, the light-colored alumen being useful in brilliant colors, the dark-colored black or very dark colors.

Certain paint colors were extremely expensive. This added value – both monetary and symbolic – to any work in which they were used. For example, in the more than 50 frescoes he painted at the San Marco priory in Florence, with Cosimo dei Medici financing the work, Fra Angelico -- true to his monastic principles -- used just a single passage of pure ultramarine blue. He used it only in the most prominent fresco, to highlight the importance of the subject: coloring the Virgin Mary’s cloak the unique clear blue that only ultramarine could produce.

Ultramarine is the oldest and most technically specific device whereby a painter and his patron could honor a distinguished personage. That is because ultramarine was by far the most precious of all the painter’s materials. It's beautiful, it’s extremely resistant to the damaging effects of light, and it’s very rare. Consequently, painters’ contracts of the period frequently specified the exact quantity of ultramarine that the patron authorized the master to use. At San Marco, whose frescoes are distinctive for technical as well as aesthetic reasons, the message is clear: in the spirit of humility, the opulent blue pigment appears at San Marco only on the Virgin Mary and only in the Chapter Room.

Referring to the importance of identifying historically-true colors in art restoration, Stephanie Reitz, in an article in the ArtInfo newsletter says, “The implications go beyond aesthetics to cold cash. For example, the use of pure Prussian blue—the first synthetic color of the Industrial Revolution—can cause a painting's value to skyrocket.” So what’s changed?

Theoretical and practical approaches to art restoration change over time, influenced largely by available technologies, and also by cultural trends.
Until a quite recently, restoration and preservation was a “best guess” proposition, with the restorer -- typically an artist by training -- making assumptions about what paints, varnishes and other materials were originally used. Results varied from good to disastrous. Restorers today often find themselves having to undo ill-advised past restoration efforts.

In much the same way as a good historian pursues the truth about what happened at a distant past point in time, a good art restorer seeks to know the facts related to the creation of a particular artwork.

Today chemists are involved in restoration, using invisible-to-the-naked-eye samples of paint taken from the piece. Henry DePhillips. a Trinity College chemistry professor says, ''The whole goal of art conservation is to preserve the original vision of the artist, not my vision of what it could or should be,'' alluding to the guesswork in outdated theories of restoration.

Using cutting-edge science chemists can identify the mix of ingredients – like iron oxide, mercury, titanium dioxide, lapis lazuli -- that constitute various colors. For example, titanium dioxide is what made white, white.

“If you're going to restore a piece of art to the way it was on the day it was finished, you need to know exactly what materials they used. Our job has been done correctly if you, a viewer of the piece, cannot tell that anything has been done,'' DePhillips said. ''That is meeting our responsibility to history.''