George O'Fair's Museum in Santa Fe, New Mexico, contains about 140 oil paintings by an American artist, as well as thousands of additional works from the fruitful O & Kifa. But oil paintings develop tiny bubbles about pin size, almost like acne, for decades. At first, defenders and scientists believed that they were sand that got into the paint. But then the performances grew, spread and began to disintegrate, which led to an increase in anxiety.
An interdisciplinary team of scientists from the Northwestern University is now exploring this mysterious "disease of the paint", using an inexpensive, portable tool that allows the user to quickly and easily depict the surfaces of paintings using a smartphone or tablet. They demonstrated a new technique last week at a conference of the American Association for the Advancement of Science in Washington.
This "disease of the paint" is not limited to Kifa's creativity . Conservatives have found such a deterioration in oil masterpieces for all periods of time, including Rembrandt's work. Chemists conclude that blisters are actually soap with metal carboxylates, which are the result of a chemical reaction between metal ions in lead and zinc pigments, as well as fatty acids in a paint-using environment. Miles begin to stick together, forming blisters and migrate through a film of paint. "They can form exudates on a surface that closes the drawing itself, creating an insoluble film, or a transparency effect, so you can view those layers that were not intended by the artist," said Mark Walton of the Northwest University.
About 70 percent of all oil paintings have a deterioration associated with metal soaps.
In fact, about 70 percent of all oil paintings have a sharp deterioration associated with soaps from metal carboxylate to varying degrees. to Walton "Often it's benign, and nothing will happen in terms of deterioration of the paint, but in some cases it's pretty devastating," he said. This applies to Kiefa's work, where determining the magnitude of the deterioration is extremely important.
Walton is co-director of the Center for Northwestern Research in the Arts (CSSA), dedicated to working with cultural institutions. the scientific assistance needed to solve such problems. His northwestern colleague, Oliver Cossairt, almost visited the Chicago Arts Institute before switching to computer vision and computational visualization, so that he was the perfect choice to work with Walton on the easy, accessible documenting tool how the performances evolve over time.
Two men met with Dale Crohnright, head of conservation at the Museum of the O'Keyf, working with the Chicago Institute of the Arts on a project depicting the shape of the surface of the Paul Gauguin collection several years ago. Kronkright told them about the unusual performances he noticed in many of Kiefa's paintings during a museum museum survey. Some paintings have more pronounced performances than others, but even when the conservatives restored the most damaged cloths, the appendage returned.
working on this idea, using 3D-surface measurements [techniques] to paintings as an analysis tool for a while, "said Cossairt." We believe that it is possible to develop tools measuring using devices that are readily available to museum conservators to get a little more information that the conservator will need to make a more informed decision. "It is based on a technique called reflection transformation, which usually involves a lot of large, bulky including a dome containing several light sources
Most museums do not have the financial resources to purchase and service such equipment, so Cossairt has developed a more convenient option. "We want to implement these 3D measurement systems as cheaply as possible and put them in the hands. as many people as possible, "he said. His method uses an LED flash or a liquid crystal display of a smartphone or tablet as a convenient light source to display light from the surface of the canvas and capture these prints up the front. S camera.
This is an elegantly simple, intuitive idea that looks like a skyscraper with mirror windows that work like a mirror. "You see a reflection of another skyscraper, or some other structure, and you notice that the lines are bent when they have to be straight," said Cossairt. Thus, the surface of the window should be curved, not flat, and this allows you to define the 3D-form of the window.
A similar principle also applies to the Cossairt visualization tool. If the surface of the painting is completely flat, you will receive an accurate reflection of the patterns on the canvas. If the sample causes unevenness, "the picture locally distorts and stretches and shrinks in different areas," – he said.
Ultimately, Cossairt hopes to build the equivalent of a portable device "Tricorder" for nature conservation museums. where they could take a smartphone, waving it in front of the canvas, and software will be installed that can automatically analyze when the screen moves through the object by seaming the field of view. The following images can be compared with the previous ones to get an idea of what has changed since the last measurement.
YouTube / North- West University
Another colleague from the Northwest, Aggelos Katsaggelos, develops these software tools. "Technology uses machine learning to distinguish whether there is a softening texture or something benign, like a stroke," said Katsaggelos. "Then, for protrusions, we extract stats: density, size, and shape. "The Cohairt Tricorder tool never works replacing the synchrotron, which will always be a higher-power tool, a higher resolution for this kind of presentation.This is often used for non-destructive analysis of works of art and archaeological artifacts.For example, scientists used synchrotron radiation that reconstructs the portrait of a peasant written by Vincent van Gogh, who The artist repainted when he created the "Grass Patch" in 1887. from collecting and bringing it to the synchrotron, and access to such objects is limited, since synchrotrones are useful for many different applications and are in great demand among scientists. Thus, the Cossairt tool is a useful additional method.
The next step in developing a conservative solution is to better understand what specific factors contribute to selection, including environmental factors such as humidity, temperature and direct sunlight. Walton's team is now experimenting with surrogate paintings in the lab, creating their own metallic soap reactions and documenting the process. Kronkright provided a ton of information about the history of travel and exhibitions of the collection, since the paintings that traveled at public exhibitions seemed more and more prominent.