In 1973 The Center for Art Conservation Studies (CASS) was established at the University of
California, San Diego (UCSD). This was in response to demonstrations that were conducted during
January-March 1972 in Venice for UNESCO, Venice in Peril, International Fund for Monuments,
and the Italian Petroleum Institute (ENI). The feasibility investigation explored in-situ pulsed
holography, holographic interferometry, and laser ablation divestment for applications in art
conservation practice. During subsequent decades scores of UCSD graduate and undergraduate
students as well as conservators, conservation scientists, academics, and engineers who resided in
CASS as “Visiting Scholars” contributed to advancing the understanding and performance of
radiation technologies in the arts. Several technologies in addition to those involving optical
wavelengths were also investigated to aid in art conservation and conservation science. Magnetic
Resonance Imaging (MRI) and Nuclear Magnetic Resonance (NMR) were employed to detect and
map moisture within masonry. Lead isotopic analyses revealed authenticity and provenance of Benin
bronzes. Inside-out x-ray radiography facilitated the detection of defects in stone. Ultrasonic
imaging was introduced for the mapping of fresco strata. Photoacoustic Spectroscopy (PAS) was
used to characterize varnish layers on paintings. Digital image processing was introduced in order to
detect and visualize pentimenti within paintings as well as to perform virtual restoration and provide
interactive museum displays. Holographic images were employed as imaginary theater sets. In the
years that followed the graduation of students and the visits of professional collaborators, numerous
other applications of radiation ablation began appearing in a wide variety of other fields such as
aircraft maintenance, ship maintenance, toxic chemical remediation, biological sterilization, food
processing, industrial fabrication, industrial maintenance, nuclear decontamination, dermatology,
nuclear weapons effects simulation, and graffiti control. It was readily apparent that the customary
diffusion of advanced technologies from science and industry into the art conservation field had
been reversed. In this paper we trace the migration and adaptation of radiation divestment
developments in art conservation to numerous applications in science, industry, and consumer
products. Examples described include the robotized hybrid “Flashjet” aircraft paint stripping system,
the “Novotronic” anthrax remediation installation in the Pentagon Building, the InTa automated
graffiti removal system employing a carbon dioxide TEA laser, the Bellalite body hair removal
product incorporating flashlamp technology, and the Foodco line of optical radiation products for the
sterilization of food products. The Foodco products are also applied to the sterilization and/or
pasteurization of beverages and beverage containers. A similar device has been adapted to seafood irradiation in order to increase shelf life, as well as for the ablative removal of skin and scales. The
Goodyear Tire and Rubber Company, to etch logos and identification information into the sidewalls
of pneumatic tires, also developed a flashlamp-based ablation technology. The founders of the
CYMER Corporation applied UV irradiation technology to the manufacture of high-performance
integrated circuits (viz., memory chips, etc.) In several instances former CASS students and Visiting
Fellows consciously adapted the above-learned art conservation methodologies to still other
purposes. Thus, these examples of technology transfer may be termed: “Art in the service of
Science.” Alternatively, it is evident that many associated innovations developed from independent
activities, unconnected serendipity, or through the normal diffusion of information and knowledge
In recent years there have been enormous advances in nautical archaeology through developments
in SONAR technologies as well as in manned and robotic submersible vehicles. The number of
sunken vessel discoveries has escalated in many of the seas of the world in response to the
widespread application of these and other new tools. Customarily, surviving artifacts within the
debris field of a wreck are collected and then moved to laboratories, centers, or institutions for
analyses and possible conservation. Frequently, the conservation phase involves chemical
treatments to stabilize an artefact to standard temperature, pressure, and humidity instead of an
undersea environment. Many of the artefacts encountered at an underwater site are now
characterized and restored in-situ in accordance with modern trends in art conservation. Two
examples of this trend are exemplified by the resting place of the wreck of the Titanic in the
Atlantic and the Cancun Underwater Park in the Caribbean Sea. These two debris fields have been
turned into museums for diving visitors.
Several research groups have investigated the possibility of adapting the well-established analytical
tool Laser Induced Breakdown Spectroscopy (LIBS) to in-situ elemental analyses of underwater
cultural, historic, and archaeological artefacts where discovered, rather than as a phase of a salvage
operation. As the underwater laser ablation associated with LIBS generates a “snowplough”
shockwave within the aqueous matrix, the atomic emission spectrum is usually severely attenuated
in escaping from the target. Consequently, probative experiments to date generally invoke a
submerged air chamber or air jet to isolate water from the interaction zone as well as employ more
complex double-pulse lasers. These measures impose severe logistical constraints on the
examination of widely dispersed underwater artefacts. In order to overcome this constraint we
report on water-immersion LIBS experiments performed with oblique laser irradiation and spectral
detection at the complementary angle so as to view emission from behind the shockwave. Targets
of silver, gold, and copper have been studied. It is found that this approach enables LIBS detection
in water both in emission and in absorption. It appears that underwater inverse LIBS may be
especially useful in underwater archaeology.
In 1964 a human skeleton was discovered in the sediments of the Columbia River near Kennewick, Washington (the
extreme northwest portion of the United States). Subsequently, these bones were analyzed in several scientific
laboratories and dated at more than 6000 years BP. Now known as "Kennewick Man", the remains are associated with
the "Clovis Period" and, indeed, a Clovis spear point was discovered imbedded in the bone of the pelvis. Equally
significant were DNA results indicating the individual was of Caucasian racial origin. Consequently, this sensational
archaeological discovery stimulated widespread debates concerning the populating of the Western Hemisphere: the
migration routes, the eras of the waves of migration, and the peoples involved. In spite of the enormous historical and
cultural significance of the Kennewick find, contemporary Native American Indian Tribes (Nez Perce, Umatilla,
Yakima, Wannapum, Colville) prevailed in the courts and were awarded the bones for a "dignified" and "sacred"
reburial on the Columbia River bank at the discovery location. Whereas this reburial may have been culturally sensitive,
it was both dangerous and imprudent. The internment site is only a short distance downriver from one of the most
contaminated nuclear repositories in the world. The Hanford Nuclear Reservation has twelve shutdown atomic reactors
that were constructed almost seventy years ago and built for the production of plutonium. The facility also encompasses
five chemical-processing complexes for the extraction and refining of plutonium. During the past few decades many of
the reactors, as well as their single-wall waste storage tanks and ponds, have deteriorated and have been leaking
radioactive and toxic-chemical waste into the local aquifer. This contaminated ground water has been seeping ever
closer to the banks of the Columbia River and the resting place of Kennewick Man and other associated (yet to be found)
artifacts. Without remediative steps the toxic flow will continue past Kennewick to threaten cities such as Portland with
a Chernobyl-like tragedy. Consequently, a remediation program was initiated to drain the leaking tanks and ponds so that
the toxic wastes could be buried elsewhere and/or transferred to more secure double-shell reservoirs. Unfortunately,
hazardous substances adhere to pores and corrosion on the vessel walls after draining. This poses problems when
disposing of refuse materials and hardware from the site. It has been experimentally determined that this hazardous
surface contamination may be ejected by means of radiation ablation. It was concluded that this is most effectively
accomplished with underwater flashlamp irradiation. In this manner the dislodged surface contamination is freed to float
in the water and is then captured and concentrated by the filters of the fluid circulation systems. The final phase of the
project was assistance in designing a Stonehenge-like monument to celebrate the cleanup of the Hanford Reservation
and the removal of the radioactive threat to the final resting place of Kennewick Man ("The Ancient One").
Ever since the dawn of the 20th Century there has been a universal consensus that Alphonse Mucha launched the
sensation that became known as Art Nouveau. This event was associated with the appearance of his Gismonda poster
promoting the Sarah Bernhardt play of that name in Paris in 1894. At an estate sale in 1954 a small collage bearing a
likeness of Mucha's Gismonda was offered. It had been fabricated by gluing slivers cut from sixty postage stamps to a
20cm ceramic tile. Digital computer image enhancement was applied to the collage design, initials on a walking stick
from the same estate collection, and the Mucha poster. These geometrical analyses revealed that the collage is more
detailed than the Mucha "original". This led to our hypothesis that the famous poster was a hasty photographic
plagiarism of the intricate ceramic-tile collage. Image analyses of the initials on the companion walking stick revealed
conformity with the famous enigmatic "P GO" monogram of Paul Gauguin. We conclude that Gauguin rather than
Mucha created the Gismonda composition. Historical evidence suggests that, while Gauguin was in Brittany recovering
from injuries sustained in a fistfight, Annah la Javanese stole his possessions and took them to Paris where her next
lover, Mucha, copied the collage and presented it as his original poster design.
The assassination of US President John F. Kennedy on November 22, 1963 transformed the US political landscape as
well as the trajectory of subsequent world history. The venue of that tragic event in Dallas was Dealey Plaza,
encompassing the "grassy knoll" and the adjacent book-depository and courthouse buildings. For the past forty years the
site has undergone a series of conservation/preservation projects in order to make it more suitable for those visiting
either in homage or out of curiosity. One such project concerned the deterioration of ironwork within the "Old Red
Courthouse". The building architect noted that both stairway railings and floor-support trusses were corroding and
deteriorating at accelerating rates. In most situations of this sort the iron would be sandblasted and repainted. However,
in this instance sandblasting was inappropriate due to environmental concerns and logistical limitations. Furthermore,
historical authenticity criteria dictated that the metal be preserved with its original unpainted finish. In order to avoid
excessive floor loading (in this fragile old building) and the generation significant environmental air pollution (within
urban Dallas) the general contractor (Avery Mays, Inc.) opted to evaluate photonic divestment. Both laser cleaning and
laser glazing were assessed for efficacy and cost effectiveness. Xenon-flashlamp irradiation was evaluated both with and
without citric acid augmentation. Citric acid matrix-assisted flashlamp treatment was selected for the preservation of the
courthouse ironwork. This decision was based on three advantages over laser treatments: higher speed and cost
effectiveness, preservation of the historic "Oliver Foundry" logo markings, and the chemical passivation and rust
resistance of the final surface patina.
In 1972 Ente Nazionale Idrocarburi sponsored a program to holographically record the images of Venetian sculptural treasures for archival purposes. At Laboratorio San Gregorio, where the initial holography took place, G. Musumeci and K. Hempel suggested an experiment to determine whether the concentrated beam from the ruby holographic laser could ablate black-patina crusts from decaying marble. Initial success of a laser-divestment test on a Palazzo Ducale capital launched a search for funding to enable a full-scale laser-conservation demonstration. Later, at a Caltech reunion one of the author's physics professors (Carl Anderson, the discoverer of mu mesons and the positron), noting the prominence of the Venice Film Festival suggested our approaching the motion picture industry. Many years earlier Anderson's Caltech classmate, Frank Capra, had supported the research that led to the discovery of cosmic-ray-generated antimatter on Pikes Peak. (After Caltech, Capra had become a director at Columbia Studios.) Anderson's chance comment led to an introduction to producer Jack Warner at a festival screening of his "A Clockwork Orange" in Asolo. He and his friends contributed US$5000 toward the laser conservation of a marble relief of "The Last Supper" in the Porta della Carta of Venice. This work was conducted in 1980 under the direction of Arch. G. Calcagno. In 1981 it was found that the granite veneer or the newly completed Warner Center Tower had been stained during transit from the quarry. The Venice laser successfully restored the veneer, thereby returning the Warner Brothers' favor.
Since the inception of the laser-divestment process, emphasis has focused on the treatment of reasonably durable materials. Marble, limestone, sandstone, and bronze are foremost among these. In most situations the objective of laser divestment is the removal of superficial corrosion or chemical-decomposition products. To a lesser extent laser ablation is also used to treat diverse surface problems for a spectrum of other historic and artistic substrates such as paper, vellum, ivory, paint, and plaster. Although materials of this sort are not particularly strong, their optical, thermodynamical, and mechanical properties are sufficiently propitious to enable successful laser treatment (with the exercise of precise control). There is another, quite different, cleaning problem encountered in the maintenance of museum collections. This is often referred to as "dusting" (in contrast to "divestment" or "conservation"). Vacuuming, wiping, blowing, and feather dusting are used most often to improve the cosmetic appearance of museum objects after dust and aerosols have accumulated on exposed surfaces. However, many collections include extremely friable pieces composed of feathers, fir, hair, plant fibers, or mummified skin. Conventional dusting may be impossible in such instances. From experimental observations and theoretical analyses we speculate that at very low fluxes laser-induced acoustic and electrostatic forces are responsible for the ejection of debris. Laboratory experiments demonstrated that laser dusting was effective on feathers and textiles, The practical viability of laser dusting was demonstrated by laser-cleaning two very large sand sculptures by San Diego artist C.R. Faust. In contrast, all conventional cleaning techniques damaged the surface by dislodging sand grains.
The Center for Art/Science Studies (CASS) was established at the University of California, San Diego (UCSD) in 1974 in order to foster formal interactions between students and faculty in the arts with students and faculty in the sciences. The majority of these cross-disciplinary activities have involved members of the Schools of Visual Arts, Theater, Oceanography, Physics, Medicine, Chemistry, Space Sciences, and Applied Mechanics. In its early years CASS developed into a program of "science in the service art." Technologies such as isotopic analyses, holography, laser illumination and surface modification, digital-computer image processing, ultrasonic imaging, and magnetic resonance imaging (MRI) were applied to art in the areas of display, history, interpretation, performance, restoration, conservation and creation. For the most part the stimulus for developing such connections came from searching for ways of applying current scientific innovation to the arts. However, it was a surprising revelation to eventually realize that the artists were contributing to the sciences, as well. This reversal that we experienced has roots going back to the earliest civilizations and includes notable recent artistic contributions to general relativity, quantum electrodynamics, and cosmology. At the present time the activities of CASS are being carried on by the Center for Research in Computing for the Arts (CRCA).
Just as lasers have found countless applications in science, industry, medicine, and entertainment, an array of real and potential uses for lasers in art-conservation analytes and practice have been investigated over the past thirty years. These include holographic recording, holographic recording, holographic nondestructive testing, laser-induced ultrasonic imaging, laser-scattering surface characterization, atomic and molecular analyses, photoacoustic spectroscopy, surface modification, as well as surface divestment and cleaning. The initial endeavors in exploring and assessing the utility of these tools for art conservation are recounted for investigations involving ruby, glass, ion, YAG, carbon dioxide, dye, and excimer lasers as well as high-intensity nonlaser light generators such as xenon flashlamps and argon pinchlamps. Initially, laser divestment/cleaning was, by general consensus, the least plausible laser application in art conservation. In the past ten years it has emerged to dominate all the other applications noted above. Today, at least a dozen firms supply user-friendly laser systems optimized for a range of art-conservation divestment applications. The first-generation laser-cleaning tools are essentially a laser, a beam-delivery device, and a debris- collection accessory. Advanced developmental work has turned in large measure to ancillary subsystems for more sophisticated process control. Of particular importance are acoustic, optical, spectral, EMP, and electronic-vision process control. Beam direction may be via manual, translational-scanner, or robotic beam positioning implemented by means of fiber optics, minors, or prisms and computer control. Substrate thermal alteration and debris redeposition may be minimized or avoided through the incorporation of a gas jet, fluid or fluid jet, or dry-ice blast.
Since the turn of the century there has been widespread acknowledgement that Alphonse Mucha inspired the birth of the Art Nouveau movement when he created the 'Gismonda' poster advertising the opening of the Sarah Bernhardt play of that name in Paris in 1894. At an estate sale in 1954 a small collage bearing a likeness of the Mucha 'Gismonda' was offered. It was composed of fragments of sixty postage stamps glued to a small ceramic tile. Digital computer image processing has been applied to the collage design, scratches on the handle of a walking stick in the same collection, and the Mucha poster. From comparative analyses of the enhanced 'Gismonda' images it is revealed that the little collage is considerably more detailed and compete than the Mucha 'original'. Thus, it is concluded that the poster is a hasty photographic plagiarism of the intricate collage. Further image processing of the scratches on the handle of the walking stick and the collage reveal them to conform to the famous and enigmatic 'P GO' monogram signature of the artist Paul Gauguin. Thus, it follows that the original design was created by Gauguin rather than by Mucha. It may be that while Gauguin was in Brittany recovering from injuries sustained in a brawl his former lover, Annah la Javanese, pilfered his belongings and took them with her to Paris and her next lover, photographer-designer, Alphonse Mucha, who copied the collage and offered it as the Gismonda Poster.
Jay DeFeo's sculptural-painting was originally begun as a 'concept with a center'. This DeFeo work was pivotal to both her artistic recognition and development It epitomized the beat- culture's newly discovered creative freedoms encouraged during the art renaissance of the period that has come to be known as America's Chamelot. Jay DeFeo's Rose was the culmination of an almost ritualized performance-art process of creation and destruction that spanned the years 1958 through 1965 and resulted in a 0.4 X 2.5 X 3.2 meter, 100 kilogram composite-laminate painting/artifact. When the artwork begun to crumble twenty years ago it was totally encased in approximately 10cm of steel-reinforced plaster for structural support. Here we will describe the solids-imaging techniques considered and utilized in determining the painting's internal composition to aid in safe extraction of the artwork from its plaster tomb followed by complete restoration. Our imaging goals were first, locate the interior plaster-paint boundary and second, characterize the size, shape and relative geometry of voids and artifacts in the paint composite laminate to facilitate the positioning and embedding weight-bearing pins.
A high-pressure laser-guided gas-embedded plasma pinchlamp is described for the generation of intense UV radiation. It has been configured to optimize energy transfer from the storage PFN. The output energy peaks within the spectral range 150 - 250 nm with a pulsed power of 20 MW at 10 Hz. The device employs a working gas of argon at 3 AMAGAT and has a pulsewidth of 20 microseconds. The results of exploratory surface modification experiments with the pinchlamp are reported. These include the destruction of chemical warfare agent simulants, asbestos, petroleum, and insecticides on surfaces as well as semiconductor annealing. In addition it was determined that various aircraft coatings are able to be removed from aluminum and composite substrates. These coatings included primers, top coats, and anti-erosion materials. This pinchlamp technology potentially fills a performance gap in the hard ultraviolet between flashlamps and lasers. On the one hand it offers a peak power and brightness comparable to parameters customarily associated with laser technology. On the other hand it possesses the efficiency, simplicity, and scalability often encountered with conventional flashlamp systems.
When created in 210 BC, the 6,000 terra cotta warriors of the Mount Li tomb near the ancient imperial Chinese capital city of Xi'an were emblazoned with dramatic colors. Previously, it had been thought that this polychrome glaze had been entirely consumed in an inferno that swept the tomb shortly after its completion. Careful manual control of laser divestment experiments on the statues during the archaeological excavation of the site has revealed that faint charred vestiges of the original polychromatic glaze still exist. Unfortunately, as a consequence of the long burial, the terra cotta statues with their cooked polychrome glazes are encased in tenacious mineral deposits. Consequently, laser removal of the mineral encrustation requires tedious human implementation in order to avoid damaging the very delicate underlying statue surfaces. A real-time spectral control system for precise automated laser cleaning of archaeological objects is described. It has improved the results, accelerated the process, and relieved the operator tedium in the recovery of this Qin Dynasty polychrome as well as in the cleaning of ancient coins from other archaeological sites.
In the late 19th Century the Old Executive Office Building (OEOB) was constructed adjacent to the White House. Over the years it has housed many of the departments of the executive branch of the U.S. Government. By the turn of the century most of the original painted designs on its walls had been covered over with various `institutional' wall paints. In recent years there has been a move to restore may of the private and public rooms in the OEOB to their original appearance. In the case of the Office of the Vice President during a brief period when the office was vacant, the overpaints were removed in small areas to reveal glimpses of the original wall designs. These design fragments were then photographed and digitally scanned. The techniques of digital computer image enhancement were next employed to clarify, extend, replicate, and rotate these designs. An image of the office was then restored to show its original appearance. Subsequently, the office itself was restored. Before and after images of the office are presented along with the computer-generated reconstruction that guided the restoration work.
The techniques of digital computer image processing have been employed to investigate the characteristics of paintings by the Italian master, Raphael. In particular spectral histograms have been generated for several of his paintings for individual areas such as hair, face, and garments. It was found that the palette employed by the artist does exhibit regularities. Similarly, spatial frequency histograms of like areas of his different paintings also show certain uniformities. Thus, the first steps have been taken in developing a `fingerprint' for the chromatic tonality and impasta characteristic of this artist's hand. Such information may be of use in trying to attribute controversial paintings where historical data are lacking and chemical data are ambiguous. This trial `fingerprint' has been applied to an unattributed Italian painting known as the `Madonna della Divino Amore.' Although the match to the `Raphael fingerprint' is not perfect it does offer sufficient encouragement to suggest that further investigations into the nature of its materials and its history are warranted.
There is a great deal of uncertainty and controversy surrounding the artwork legacy of Rembrandt van Rijn. Much of the difficulty stems from the dearth of reliable contemporary documentation covering the artist's activities as well as the great number of students who painted in his studio. Consequently, attributions have rested heavily upon subjective assessments of style and execution, together with whatever historical evidence can be uncovered. The dilemma associated with selecting those works which should be assigned to Rembrandt is complicated further by his fame and the potential for great financial return from the discovery of new pieces. In recent decades this dilemma has been alleviated to a considerable degree by the introduction analytical scientific methods for analyzing (and, in some cases, dating) the materials of an artwork. However, the greatest impact of materials analyses has been to throw out many style-based attributions after finding that the materials were inconsistent with the artist's legacy. Thus, materials analyses typically play a negative role in showing that an attribution is impossible rather than proving that the work in question was by the artist in question. On the other hand a new opportunity is at hand as a consequence of the emergence of digital computer image processing technology. It is now possible to apply this tool to the direct attribution of a painting through analyses of statistical properties pertaining to palette, albedo, and impasta. This paper describes the first efforts at creating a data base on the properties and statistics of Rembrandt portraits so as to provide a basis for determining which should be included in the body of his works, rather than which should be excluded.