Month: May 2010

Education As The Basic Tool of Conservation in the 21st Century

The third talk of the morning session was delivered by Paper Conservator Eugenia Guidobono of the National University Institute of Art in Buenos Aires, Argentina. Her talk titled, Education As The Basic Tool of Conservation in the 21st Century, grew out of the results of her Master’s thesis on improving collections through preventive conservation. She examined conservation in public museums via surveys and interviews. She briefly discussed the history of conservation in Argentina with the introduction of preventive ideas in the 1980s brought about by loan stipulations imposed by other institutions. In the 1990s the Smithsonian began to conduct courses in Argentina.

Guidobono then went onto focus on her survey of museums within the Entre Ríos Province. She found that of the museums that responded 18% were art museums, 13% had general collections, 62% were history museums, and 6% solely museums of Anthropology. 94% of the museums listed for this one province were part of the Town Hall (run by the state). 81% of these museums do not operate with a fixed budget and have to rely on political affiliations to raise money.

There are no regulations in place for professional training. She emphasized that local universities only have a few museum courses and that in general there is a total lack of conservation training available. Of some 133 employees interviewed, only 4% have a university education. 11% of those practicing conservation in museums in the Province of Entre Rios have conservation training, while 89% of those practicing do not. The author stressed that while there are national laws in place for heritage protection they are not regulated. The Town Hall authorities are neglecting the needs of the collections and she found that the human factor is the greatest detriment to the collections surveyed.

She called for a change to the mindset of society, with preventive conservation becoming the concern of all museum staff members. She concluded with images of storage areas in shambles versus storage areas in institutions that have worked on maintaining preventive conditions.

2:30 – 3:00 p.m. Re-thinking the Cleaning of Claes Oldenburg’s Floor Cake

Margo Delidow, Sculpture Research Fellow, The Museum of Modern Art; and Cynthia Albertson, Paintings Research Fellow, The Museum of Modern Art

Just in time for dessert, this unique treatment of Oldenburg’s Floor Cake (Giant Piece of Cake) brought together objects and paintings conservators at the Museum of Modern Art to investigate the painted sculpture’s treatment history and develop methods for re-treatment.

Well organized and clearly presented, the duo provided images of the artist with a number of his painted oversize food artworks, created for the Green Gallery, NYC show in 1962. Since acquisition by MoMA in 1975, Floor Cake has been heavily exhibited including extensive travel, and has undergone at least two treatments, one of which involved surface cleaning using chelating agents.

The project was approached scientifically, using optical microscopy to reveal the artist’s technique, including changing the color/flavor of the cake ‘drop’ a number of times. FTIR was used to examine the original canvas fibers for evidence of cleaning residues from the previous treatment. The pH and conductivity of the surface dirt were measured in order to concoct the appropriate Modular Cleaning Program solution. Cleaning solutions were developed based on the results of considerable research done by Chris Stravroudis and others as presented at the Cleaning of Acrylic Painted Surfaces: Research into Practice (CAPS) colloquium held on July 7-11, 2009 at the Getty.

The treatment of this object provided a useful practical application of this research, including the investigation into different solution delivery methods (PVOH sponge vs. cotton swab). It was particularly interesting to see this acrylic painting treatment in the OSG session, as these types of surfaces are going to become increasingly problematic for sculpture conservators.

Additional information regarding this treatment, including future testing, can be found the the Museum of Modern Art conservation blog, INSIDE/OUT.

Joanna Phillips’ fascinating presentation explored the different ways in which museums must look at objects that have moved from being purely functional to being inherent parts of an artwork: electronic display equipment.

From the 1960s onward, artists created moving-image and sound works that were dependent on current technology for their display in the museum. Once that technology becomes obsolete, however, conservators face a choice: maintain old equipment of often-dubious functionality, or migrate the work to new technology that may not have been available to the artist at the time of creation. Critical to this decision: determining whether equipment is merely an accessory to the artwork – something akin to a pedastal or a vitrine – or an essential component of the work.

Phillip, conservator for time-based art at the Guggenheim Museum laid out the ways in which playback equipment can change over time from accessory to essential component. The Guggenheim, like many museums, maintains a pool of video playback and display equipment that can be used for multiple works: one DLP projector, for example, could be suitable for any number of projected video works. But as equipment becomes obsolete, what was once common and easily available technology becomes rare and difficult to obtain. When this happens, equipment that is critical to maintaining an artist’s vision of a work may be assigned to a specific artwork to insure that it will be available for that work’s display in the future.

The most striking example given by Phillips is a video installation by Marina Abramovic, Cleaning the Mirror I (1995). The piece consists of five video channels played back on a stack five color cathode ray tube (CRT) monitors. When the piece was created, CRT monitors were common and plentiful. The artist did not require specific sizes or models for the monitors, only describing their approximate size and appearance. The technology was so commonplace that further specificity didn’t seem important.

Within the last few years, however, CRTs have become almost completely obsolete, and are increasingly difficult to obtain. New monitors using LCD or plasma technology have a completely different aspect ratio – 16:9 vs. 4:3 – that would change completely the appearance of the work (anyone who has suffered through an old movie that has been “stretched” to fill a 16:9 monitor understands the damage this change could cause to a video artwork.)

Phillips laid out the detective work necessary to find five monitors suitable for installing Cleaning the Mirror I, and the complex technical process required to bring them up to optimum performance. These five monitors will now be dedicated to the work, insuring that it can be displayed according to the artist’s specifications – for now. But as Phillips pointed out, these monitors can only be maintained for so long.

She also described an early work by Korean-American artist Nam June Paik – Random Access (1963/1999) which consists of strips of ¼” analog audiotape glued to a wall. Nearby is a modified audiotape playback deck with a detachable head. Philips also described an early work by Korean-American artist Nam June Paik – Random Access, (1963/1999) which consists of strips of ¼” analog audiotape glued to a wall. Nearby is a modified audiotape playback deck with a detachable had. Viewers can run the playback head over the tape to hear what’s on it. As with Abramovic’s CRT monitors, Paik’s analog audiotapes were extremely common technology when the work was created. Today, however, the equipment is extremely difficult to come by.

Complicating the conservation history of the work is the fact that the modified deck that the Guggenheim acquired with the work was actually modified by Paik’s studio (as opposed to Abramovic’s monitors, with which the artist had had no direct content.) Phillips explained the categories that the Guggenheim assigns to its equipment: “Artist-provided,” “Artist-approved,” or “artist-specified.” Paik’s audiotape deck falls into the first category. Phillips highlighted the peculiarities of the deck in question: it had been crudely modified by the artist or his studio – at one point, when electronic circuitry needed to be replaced, rather than unscrew and open the deck, someone knocked a hole in the back and hot-glued in the required capacitors. The clear hand of the artist and his collaborators marks this particular piece of equipment as an essential part of the work.

A pair of fascinating papers by Walter Forsberg and Elizabeth Seramur gave two views of just how much effort can be required to make sense of artist-created digital files – even files that are barely a decade old. The idea of “Digital Archaeology” – Seramur’s term – summed up the problem.

Seramur’s paper (Developing a Digital Archaeology for the Warren Spector Collection: A Case Study) traced a project that took her back to the pre-historic days of personal computing – the early 1980s, when there was no such thing as standardization of file formats, interfaces, cabling, or operating systems. The project involved recovery of word processing documents created by game designer Warren Spector, whose papers are part of the Video Game Archive at the Dolph Briscoe Center for American History, University of Texas at Austin. The media: 18 5.25 inch floppy discs – from the days when floppy discs really were floppy – containing files created on the Kaypro IV personal computer using WordStar or WordPerfect, and on an Apple IIc using Appleworks.

Key to her work was the discovery of Austin’s Goodwill Computer Museum, which was founded as an offshoot of Goodwill’s computer training program. Volunteers from the tech industries watched as a wide variety of early personal computers came into Goodwill as donations, and couldn’t bear to see these rare specimens recycled. The result was a collection holding nearly every model of early PC. The museum was able to provide a computer that could read the early files – though a great deal of trial and error was required. A lack of standardization meant incompatibility between ports, cables and drivers – even among PCs with the same make and model number. The smallest variation rendered files unreadable.

Walter Forsberg’s project had the advantage of both relatively recent files – the 1990s – and a living artist, Cory Arcangel, willing and able to consult. In this case, the subject of research was a collection of CD-Rs holding backup files made in the process of creating multiple computer works. The discs held more than 200 different file extensions, marking different file formats, many of which are tied to obscure, obsolete, or short-lived software. Frequently, the file names were obscure or meaningless, and Arcangel sometimes wasn’t able to tie the files to a project now more than a decade past. The takeaway: organize digital files and standardize file names!

The RATS talks, organized by Stephanie Porto, included a morning session on microfading, as well as afternoon talks covering a range of topics. Chong Tao and Paul M. Whitmore presented work on developing a new microfading test instrument (MFT) for light exposures that includes near-UV wavelengths. The instrument takes advantage of the effect of chromatic aberration to tune relative intensity and incorporate the 300 – 400 nm range. Using various filters, the authors have successfully tested the new instrument with good correlation to the Suntester microfade instrument.

Jim Druzik and Christel Pesme presented research that characterized the performance characteristics associated with four different instrumental set-ups. They presented data collected from seven instruments where the lens design/light probe method was varied including three bench top instruments (planoconvex, achromat, lens-less) and two portable instruments (planoconvex and lens-less). These instruments test a range of spot-sizes during analysis (0.2 – 0.5 mm). Results were tabulated using three of the CIELAB equations used to calculate color space. Based on their results, the authors are satisfied that portable MFT will return similar results to bench top instruments. Future research will include testing prepared samples in a round robin, while also further altering experimental parameters to include other light sources, as well as testing samples in air/anoxic environments.

Dale Kronkright presented microfade research and a database template for archiving and organizing this information. All work results from microfade research associated with a group of Georgia O’Keeffe watercolors in the Georgia O’Keeffe Museum collections. This work was the result of collaborations with the Getty Conservation Institution and University of Texas El Paso. The selected watercolors were well-documented with limited exhibition histories. The research also tested similar/same artist’s materials found in the artist’s studio – also in the museum’s collections. The authors analyzed all objects to characterize chemical composition using portable XRF and FTIR. In an effort to improve the conservator’s voice and make microfade results useable for curatorial and collections management staff, Kronkright et al. developed an automated database platform in Microsoft Excel to aid curatorial decisions. The database tracks remaining exhibition weeks/loan time available using a graphical fuel gauge in terms of just noticeable difference (JND). Future research will correlate accelerated fade rates with those observed in real time in order to adjust exhibition strategies.

More microfading and other RATS talk summaries coming.

The first trio of papers presented during the Architecture Specialty Group’s morning session all covered research on mortars. Brad Shotwell and Joshua Freedland, both of Wiss, Janney, Elstner Associates, asked the question “Evaluation of Historic Mortars: Is Petrography Ever Enough?” Mr. Shotwell presented a methodology for analysis of historic mortars beginning with petrographic examination. Petrography can be both qualitative and quantitative, incorporating techniques such as chemical spot tests to identify specific components and modal analysis to determine relative amounts of binder and aggregate. Several case studies were used to demonstrate the answer to the question posed in the paper’s title: it depends on the questions being asked and the goals of the project. Depending on the research goals and on the nature of the mortar being examined, ASTM C1324: “Standard Test Method for Examination and Analysis of Hardened Masonry Mortar,” which is weighted toward chemical analysis, may not be completely relevant. The approach to mortar analysis recommended by Mr. Shotwell is to begin with petrography and to supplement it with chemical analysis as needed.

John Walsh of Highbridge Materials Consulting presented “The Mortars and Concretes of Fort Jefferson: A Critical Examination of Effective Analytical Techniques for Unique Construction Materials.” The goal of the analysis was to identify the components of the mortar used at Fort Jefferson, constructed between 1846 and 1876. Mr. Walsh’s approach to mortar analysis, starting with qualitative petrographic examination and applying supplemental instrumental analysis, reinforced the first presentation of the day. As demonstrated by Mr. Walsh and Magdalena Malaj in the Fort Jefferson case study, petrography is also important to anticipate anomalies or interference that may arise during other analytical work.

In the third paper of the morning, chemical engineer Nora Perez presented her research on the mucilage additive to historic mortars in “The Application of Opuntia sp. Mucilage in the Pre-Hispanic Age, Today.” Polysaccharide extracts from the mucilage cactus has been used traditionally as an additive to Pre-Hispanic mortars to increase lime solubility, improve mechanical resistance and delay setting time. In a testing program conducted by Ms. Perez, the mechanical and physical properties of lime mortars prepared with different concentrations of mucilage additive were evaluated. Mucilage extract used as an additive to lime mortars does improve the physical properties of the mortars, makes injection mortars easier to apply and promotes the formation of a compact crystalline lattice. Biogrowth does not appear to be a concern with mortars having the mucilage additive, as the extract breaks down over time.

The second group of presentations in the Architecture Specialty Group’s morning session covered a range of topics. Victoria Pingarron Alvarez of the University of Pennsylvania presented “Performance Analysis of Hydraulic Lime Grouts for Masonry Repair.” Ms. Alvarez described research carried out in 2005 and updated with current research to evaluate low-strength grouts used for adhesion. Moderately hydraulic lime grouts were formulated with different concentrations of El Rey Superior 200, an acrylic polymer emulsion, and subjected to tests of their mechanical and physical properties. A mix of 2 parts lime, 1 part fine mason’s sand, 1 part ceramic microsphere filler and 10% solution of acrylic emulsion in water yielded a grout with low shrinkage, moderate resistance to frost and compatible tensile and compressive strengths to historic masonry. Future research related to Ms. Alvarez’s work may address the suitability of test standards, as all of the test standards used in the evaluation of the lime grouts were modified in some way.

Ben Haavik and John Childs, both of Historic New England, gave the presentation “Revisiting Realty: A Changing Approach to Environmental Control in Historic House Museums at Historic New England.” Historic New England manages over 120 buildings and 1200 acres at 36 sites, and its collections include over 50,000 objects in its house museums as well as another 70,000 objects in storage. The introduction of environmental control systems at several Historic New England house museums in the 1990s quickly resulted in problems that are currently being addressed with a revised approach to environmental control. Two case studies were used to demonstrate Historic New England’s new approach to environmental control, which is a simplified approach applied incrementally. It includes a wider acceptable range of relative humidity, a monitoring program, humidistatic heating and simplification of equipment.

The final presentation of the morning by Avigail Charnov of Historic Resources Group was “A Review of 100 Years of Site Management.” The presentation, co-authored with Jake Barrow of Cornerstones Community Partnership and subtitled “Conservation of Earthen Sites in the American Southwest,” examined the creation of national monuments and parks in the southwest and the development of conservation efforts at these sites. While early conservation treatments were not well documented and were often undertaken in a trial and error fashion, a fundamental shift in conservation practices occurred in the 1970s. This shift incorporated laboratory material analysis, increased levels of documentation, monitoring of conditions, critical evaluation of treatments and a collaborative team approach.

Following the Architecture Specialty Group Business Meeting, the afternoon session of presentations began with a paper by Mary Jablonski and Stephanie Hoagland of Jablonski Building Conservation on “Picking, Peering, and Peeling: The Evolving Field of Architectural Paint Research.” The presentation focused on lessons learned from paint studies of interior architectural spaces. Key points raised in the presentation are that paint research involves more than color matching using cross section samples. It should encompass ultraviolet light microscopy and staining, exposure windows and research on paint knowledge and decorative techniques. The Colonial Building in St. John’s, Newfoundland was used as a case study to demonstrate the importance of exposure windows and reveals. Exposure windows can reveal finishes that may be easily missed in cross section examination.

The afternoon’s second paper by Neal Vogel of Restoric LLC and artisan Andrew Delarosa was entitled “In Search of Diana & Endymion (and Walking in Edgar, Hester & Jesus’ Shoes): Researching & Restoring Lead Silhouette Windows.” Lead silhouette windows were popular in the United States between the 1920s and mid-1930s. In one case study, the McKinney Coach House in Buffalo, NY from 1927 with lead silhouette windows by the D’Ascenzo Studio of Philadelphia, Mr. Vogel discussed the challenges of restoring the windows that have missing artwork. In another case study, Mr. Delarosa described the process of recreating lead silhouette windows for the Walter Guest Apartments in Chicago to replace the windows originally designed by Edgar Miller in 1932. The recreation process included trying to recapture the hand of the original artist.

Patricia Miller’s presentation of “Identifying and Treating Aged Water Repellents on Historic Stone Structures” highlighted the point that treatments developed for specific conditions can be unsuccessful if those conditions are not well understood. Ms. Miller, of Conservation Solutions, Inc., discussed the development of film forming water repellents, primarily silicone resins, and penetrants, such as silanes and siloxanes. Two case studies, the World War I Memorial in Washington, DC and the Sutri Fountain at Vizcaya in Miami, FL were reviewed. In each case, previous water repellent treatments had to be considered when evaluating future treatments.

The final three papers of the Architecture Specialty Group session focused on the conservation of metals. Andrzej Dajnowski, of Conservation of Sculpture and Objects Studio, discussed “Removal of Clear Coat Lacquers with Lasers.” Mr. Dajnowski used the case study of the Tadeusz Kosciuszko Monument in Chicago to show the laser cleaning process. The presentation also presented the interesting possibility that the ablation process that occurs with laser cleaning may reduce copper and tin corrosion products to their metallic states. Laser cleaning can be an effective way to remove coatings from bronze sculpture, with almost no risk of damaging the surface if properly applied.

Tami Lasseter Clare of Portland State University presented “Understanding Performance Properties and Limitations of Coatings for Metals.” Ms. Clare discussed a research project whose goal was to develop a clear coating for exterior metal surfaces with a 50 plus year expected lifetime. After reviewing traditional coatings and desired properties of durable coatings, polyvinylidene fluoride (PVDF) was selected for testing and found to have promising durability performance. Durability of PVDF clear coatings can be further increased using a corrosion inhibitor such as benzotriazole (BTA) as a pretreatment and inorganic additives that reduce water permeability.

Bob Score of Harboe Architects gave the last presentation of the ASG session. His paper, “Historic Finish Analysis and Coatings Design,” presented the restoration of the cast iron storefront of the Sullivan Center, the former Carson Pirie Scott Building in Chicago. The finishes analysis was undertaken to identify the original color scheme on the cast iron storefront. A finish analysis from a previous restoration campaign was incorporated into the current study, as well as archival documentation. The challenges and considerations related to the painting work of the present restoration project included problems enforcing required curing and drying times, surpassing the 12-month maximum duration before recoating and routine quality testing conducted by the paint manufacturer to ensure coating thickness and adhesion.