The AXA Reinhardt Project

Ad Reinhardt painting in his studio, 1967

The Scientific Study and Experimental Treatment of an Ad Reinhardt Black Painting: A Presentation of the AXA Art Conservation Research Project in conjunction with the Solomon R. Guggenheim Foundation and the Museum of Modern Art

Ad Reinhardt’s Black Painting, 1960–66 (1960–66) was donated to the Guggenheim Museum in 2000 by AXA Art Insurance Corporation as a study painting after it was deemed irreparably damaged. Over the course of seven years, conservators, scientists, curators, and artists collaborated to examine the issues surrounding the conservation of this painting, which include the inherent vulnerability of monochromatic and Minimalist paintings, experimental solutions for conservation, and the associated ethics of these strategies.

Physical examination and scientific analyses of the study painting contributed to a dossier of information about Reinhardt’s working methods and earlier attempts at restoration of damages incurred by the subtle, velvety surface of this black painting. Project conservators strove to define both the significance of the work and the viewer’s perception of an imageless surface with flat planes of color, how an artist’s hand (or lack thereof) confers meaning, and how one can define the essential criteria for a painting’s authenticity. All of these essential elements inform how the conservator ultimately performs treatments of paintings in the conservation studio.

Cross-sections taken from the 9 squares ofReinhardt's Black Painting, 1960-66

Cross-sections taken from the 9 squares of Reinhardt’s Black Painting, 1960–66, viewed under visible light, at 280 x printed magnification. Photo: James Martin, Orion Analytical, LLC. © The Solomon R. Guggenheim Foundation, New York

The related exhibition Imageless shown at the Guggenheim Museum July 11–September 14, 2008, included explanatory texts, mock-ups, historical material, and analysis of samples from the study painting itself. An overview of the comprehensive research project, conducted in conjunction with the Museum of Modern Art, and funded by AXA Insurance, the exhibition featured progressive laser technologies that are being tested to expand the repertoire of conservation techniques used for subtle monochromatic surfaces. Science, art, and perception comingled in this exploration of the motivation of the artist, materials of the painting, and possible treatment strategies that may preserve artworks that rely on unattenuated surfaces to convey meaning.

Reinhardt’s painting was an ideal subject for such a study, given the artist’s meticulous attention to detail and his extensive writings on art, history, architecture, and philosophy. By understanding Reinhardt’s humor, his interest in Eastern art and philosophy, as well as his related pursuit of an essential, timeless form, one can appreciate the spirit in which these works were painted, as they compel the viewer to contemplate what Reinhardt called an “un-reproducible, inexplicable icon.”

At first glance, these monochromatic paintings appear deceptively uncomplicated; subtle shades of black carefully painted to remove all traces of the artist’s touch. With time one begins to perceive a remarkable subtlety, a quality that stems from an innovative and impassioned approach to painting materials. This was achieved by mixing turpentine with the paint, allowing it to separate and then pouring off the oil and turpentine mixture, thereby extracting the oil binder from the paint film, leaving a dense pigment that was used to create compelling and rich matte surfaces.

A cross-section taken from square 6 of Reinhardt's Black Painting, 1960-66

A cross-section taken from square 6 of Reinhardt’s Black Painting, 1960–66, viewed under visible light (left) and under ultraviolet light (right). The numbers indicate the layers that make up the complex structure of this painting. Photo: James Martin, Orion Analytical, LLC. © Solomon R. Guggenheim Foundation, New York

The inherent fragility of the underbound paint film complicates any superficial cleaning; even minor accretions can turn into substantial conservation problems, since cleaning them could create patterns on the surface or discontinuities in surface sheen. In addition to burnishing easily, the paint is easily soluble or stained and thus highly challenging to clean, consolidate, or retouch.

Conservators’ retouching of cracks, losses, and surface alterations can be successful when done well, but the results are often less than perfect. Whereas variations in color, surface, and texture on less minimal compositions help to camouflage restorations, monochromatic or minimalist paintings give conservators virtually no margin for error. Accurate reproduction of texture is essential to any successful restoration, but on monochromatic paintings even very slight discrepancies are readily perceived. For this reason, a restoration that appears seamless from one angle may distinguish itself from the well-preserved original paint with the slightest change in viewing position.

The Reinhardt study painting was tested with a variety of approaches to remove damage and overpaint, including traditional solvent mixtures, gels, poultices, and mechanical treatment . This work was done under a stereomicroscope to minimize and monitor any damage done to the surface. Ultimately it was found that traditional techniques such as those mentioned above were not successful and left the surface altered in unacceptable ways.

Scanning electron microscope (SEM) image of a cross-section from Reinhardt's Black Painting, 1960-1966

Scanning electron microscope (SEM) image of a cross-section from Reinhardt’s Black Painting, 1960–1966, showing the ground and approximately twenty paint layers, both the original and the restoration layers above. Photo by Jim Eckert, Department of Geology and Geophysics, Yale University. © Solomon R. Guggenheim Foundation, New York

A team of conservators and scientists then began examining the use of laser ablation. This technology has been used for cleaning satellites, as well as in the fields of hair removal, dentistry, and both optical and cosmetic surgery. Conservators have used lasers for the treatment of sculpture and architectural elements since 1976 and have more recently applied them to painted surfaces and works on paper, but no previous attempt had been made to treat a fragile monochrome painting using laser technology.

Tests on mockups done in the laser facility at the Los Angeles County Museum of Art prompted further investigation, and the team decided to work with world-renowned laser scientists at the Institute of Electronic Structure and Laser at the Foundation for Research and Technology (IESL-FORTH) in Crete, where the painting was tested with both ultraviolet and infrared lasers.

Laser ablation is the removal of a material due to incident light, removing the material with a high energy pulse that transforms a solid directly to a gaseous state. When a material vaporizes, a plume is observed that contains a plasmalike material comprising small molecular fragments. These fragments can be analyzed through laser-induced breakdown spectroscopy (LIBS), which facilitates accurate removal of specific materials.

The laser's penetration depth is contingent upon the beam intensity, wavelength, pulse duration, and the exposed material's ablation threshold. For painting materials, these thresholds differ considerably and depend primarily on pigment and binder compositions.

The krypton fluoride ultraviolet excimer laser was chosen as the most appropriate for this painting. The excimer laser emits short bursts of high-intensity UV light, removing submicron layers of material with very little heat production. After establishing the appropriate laser parameters, the painting was transported to Art Innovations in Oldenzaal, the Netherlands, to utilize a mechanical easel with an optical arm that enables the laser to move over a large surface in a highly controllable manner.

Reinhardt's Black Painting, 1960-66, photographed under ultraviolet light before laser treatment (left) and during treatment (right)

Reinhardt’s Black Painting, 1960–66, photographed under ultraviolet light before laser treatment (left) and during treatment (right). © Solomon R. Guggenheim Foundation, New York

Images of the study painting in ultraviolet light before treatment (left) and during treatment (right) show the difference in materials that are visible on the surface of the painting. On the left, the overall spray-painted acrylic surface fluoresces strongly while a non-fluorescent local restoration is visible at the lower right corner.

In the image on the right, areas that have been uncovered by the laser are clearly identified by their lack of a fluorescing synthetic coating. The strong difference in fluorescence reflects the differing chemical compositions of the original oil layers and the acrylic restoration layers.

Not surprisingly, a study of this innovative nature has raised as many questions as it has answered. With all available techniques, how close can we arrive to the artist’s original intent, and at what point are we willing to make or accept compromises? Should we retire a painting that we deem irreparable, or wait for the refinement of technology that may offer new methods to achieve a satisfactory surface? One thing is certain: we must begin to accept signs of age on modern paintings, just as we do for historical works. Only through sustained research and restraint can the preservation of these sensitive works be ensured. Continuing interdisciplinary dialogue between art historians, scientists, and conservators will produce the most informed and sensitive practices.

Top: Ad Reinhardt painting in his studio, 732 Broadway, New York City, 1967. Photo: © John Loengard /Time Pix

Guggenheim Collections history


Learn about the
history of the
Guggenheim Collections

A Guggenheim conservator at work

Support conservation of important artworks.

Guggenheim staff, 1968

Learn More

Visit Findings for interesting highlights from the Library & Archives collection.