42nd Annual Meeting – Paintings Specialty Group Tips Session, May 29

The PSG tips session at the 42nd annual meeting took place prior to the afternoon session on Thursday, May 29th.  The following recaps the twelve tips that were presented.  I’ve done my best to give you the most complete information possible, but please feel free to contact each tipper for more information or for clarifications.  You can also always enter your questions into the comment section below!
Tip 1:  “Texas Strappo” varnish removal, presented by Helen Houp
Helen began with a case study of a damaged painting with a thick varnish that needed to be removed.  The thickness of the varnish combined with the severity of the damage to the painting precluded the use of traditional methods of varnish removal.  A search for treatment alternatives led to the use of pressure sensitive tape for varnish removal.  The tape was applied to the top layer of varnish and then pulled away gently to remove a thin layer of material without risking the paint underneath.  It was also possible to use the tape to remove overpaint.  The method allowed for a controlled removal of the varnish and overpaint in layers without leaving behind significant residues.  I was unable to determine the type of tape that was used, but I’m sure Helen would be willing to provide details to those who may be interested.
Tip 2:  Reverse of Paintings Database, presented by Elise Effmann Clifford
Elise previewed a database for “Information on the Reverse of Paintings” that she has been developing in cooperation with the Fine Arts Museums of San Francisco, which will host the final site.  The goal for the completed database is to provide a searchable and expandable archive of shared information specific to the reverse of paintings with international access and contributions.  In the interest of security and permissions, a login will be required and it will be possible to make entries available to the general public or adjust privacy settings to limit viewing.  Members will be able to upload images with file size allowances up to 30MB.  Transcriptions and key terms will allow searches for details like canvas stamps, stencils, labels, and seals.  The project is destined for beta testing beginning some time in July 0f 2014.  People interested in taking part in the testing or submitting future contributions should email Elise.
The presentation of the database was followed by a brief question and answer period.
Q:  Will any of the information contained in the database be found through a general internet search?
A:  That will depend on the privacy settings.  There will also be terms and condition sections on the site as well.
Q:  Will uploaded images become property of the Fine Arts Museums of San Francisco once they are uploaded?
A:  No.
Q:  Will the database accept video?  What kind of images are accepted?
A:  It will not take video.  Right now it cannot take RAW images but will handle things like jpg, tif, etc.
Tip 3:  Filling cracks at the edges of canvas, presented by Kristin Robinson
Fine cracks along the turnover edges of a canvas can be very difficult and tedious to fill.  Kristen suggested using dried modostuc, which can be held in the fingers and gently rubbed over the cracks to fill them quickly and safely.  The dried material leaves very little residue and what remains can be gently wiped way.
Tip 4:  Edge lining iron support, presented by Kristin Robinson
Kristin followed her first tip with a suggestion for edge-lining.  A backing board or mat board can be folded into thirds to form a triangle, which can act as a rigid support for the iron to press against when applying an edge lining on folded margins.
Tip 5:  IMAT developments, presented by Nina Olsson
This tip focused on recent advancements of the IMAT project, which is the natural progression of an earlier project Nina introduced to the Paintings Specialty Group in a talk presented at AIC’s 38th annual meeting in Milwaukee.  IMAT refers to “Intelligent Mobile Accurate Thermoelectrical” mild heating devices.  The aim of the project is to provide conservators with a controlled and mobile tool for the structural treatment of materials.  It is worth noting that Nina is a paintings conservator but the IMAT was developed with a broad audience in mind, including but not limited to conservators of works on paper and textiles.  The details of the IMAT project are significant and advanced so this is merely a summary of what was presented at this tips session.  Links to more detailed information about the IMAT are included at the end of this summary.
The current IMAT team has developed working prototypes that should be ready for production within a few years.  The current focus is on low temperature applications that can be sustained for many hours at a time with a low voltage requirements (I wrote 70-150 degrees Fahrenheit and 36 volts, though these should be confirmed through additional resources).    The carbon nanotube heat source is galvanically insulated and has a thermosensor connected through bluetooth technology with a touch screen control for heating over time within a 0.5 degree Celcius fluctuation.  The mats will be flexible and come in various sizes, though any customizable size will be possible.
There are 3 IMAT forms at present.  The first is a standard mat that is opaque and does not offer any breathability.  The second is a black mesh mat with a gray polyurethane coating and thin silicone coating.  The third, which is still in development, is a transparent mat with silver nanotube technology.  A fourth incarnation–a textile-type mat of silk organza with silver nanowire–is next in line.
All questions regarding the history and current developments of the IMAT project can be directed to Nina Olsson.  Additional information can also be found via the following links:
PSG 2010 Postprints
H. Meyer, K. Saborowski, T. Markevicius, N. Olsson, R. Furferi, M. Carfagni. “Carbon Nanotubes in Art Conservation.” International Journal of Conservation Science. 4 (2013): 633-646.
Tip 6:  PSG Wiki, presented by Gabriel Dunn and Erin Stephenson

In May of 2013 a core team of paintings conservators formed the Paintings Specialty Group Wiki Committee under the guidance of Chief Wiki Editor Erica James.  The group worked to bring organization to the PSG wiki page.  Gabriel and Erin presented the improvements that were made to the page and announced that the group is seeking contributions.  They encouraged the PSG membership to visit the site and consider submitting material or reaching out to be paired with a liaison who can submit material on their behalf.  Any questions or concerns about the PSG wiki can be directed to Erica James or any member of the current Wiki Committee listed on the main PSG wiki page.
Tip 7:  Fume extraction, presented by Robert Proctor
Rob presented a design for a fome-cor “cabinet” that he built to enclose a painting during varnishing.  The structure can fit around a painting to contain fumes, and hoses attached to the structure will remove the fumes before they escape into the studio space.
Another fume extraction tip involved the wheels on portable fume extractors.  Rob mentioned that the ones sold with the portable extractors are expensive and mark floors.  He suggested making a mobile base using wheels purchased at a home improvement store that will not mark the floors.  As a side note, he added that it is not necessary to purchase the proprietary prefilters for the portable units because those used for home air conditioning units work just as well.
I’m certain Rob would be happy to provide details for anyone who wants more information on his designs!
Tip 8:  Building your own microscope, presented by Ria German-Carter
Microscopes are expensive and can be an especially significant cost for conservators in private practice.  When faced with the task of acquiring a new microscope, Ria decided to put together her own.  She was able to find some good quality used components on eBay and save on additional parts by purchasing through amscope.com.  She built an inspection microscope with the following specifications for under $1000:

  • 8 inch working distance
  • articulated arm
  • different camera mounting tubes
  • LED lighting
  • fiberoptics

Unfortunately, I missed the specification regarding the microscope’s magnification.  Please contact Ria if you would like more details!
Tip 9:  Laser line for cutting batting and what to do with the scraps, presented by Chris Stavroudis
Chris gave a simple but effective tip to assist in cutting a straight line in batting material.  He placed the line across the batting and was able to cut a smooth line without needing the assitance of a physical straight edge.  He suggested using scraps of batting for cleaning dishes, lab tools, or as a less abrasive material for surface cleaning.
Tip 10:  More fume extraction, presented by….
I apologize to this tipster for missing their identity!  Please comment below if this is your tip.  It described the use of a dryer tube/trunk for fume extraction rather than buying a specialized trunk.  White mesh can be put ver the tube to make it less like a dryer tube and a PVC cap can be added to the end for finish and for weight.  An angled piece, such as those used for water heater tubes, can be used to create a swivel at the end of the tube.
Tip 11:  Proper ventilation, presented by Daisy Craddock
This wasn’t a traditional tip, but is still important information.  Daisy pointed out that exhaust systems, such as elephant trunks, need to exhaust to the outside of a studio because they don’t remove all vapors and may produce precipitants.  She also reminded us that microemulsions do not get extracted at all.
Tip 12:  Storage rack solutions, presented by Kate Smith for Gordon Lewis
Gordon was not in attendance at the tips session so Kate presented his images of a storage system that involved the use of foam board.  It appeared that the foam was used as an inexpensive alternative material to create slots in his storage racks.  Gordon may be able to provide more details about his tip if interested people wish to contact him.
Thanks for the tips, everyone!

AIC’s 40th Annual Meeting – Paintings Session, May 9, “Frederick Hammersley: An Artist’s Documentation of His Painting Practice” by Alan Phenix

Pacific Standard Time is not just a time zone.  It is also the title of a Getty-funded initiative, jointly launched by the Getty Foundation and Getty Research Institute, that enabled more than sixty cultural institutions across Southern California to tell the story of the art scene in Los Angeles, California.  The initiative focuses on archives, research, exhibitions, publications, and other programs to record the region’s artistic history.  A substantial part of the project is dedicated to Los Angeles art from post-World War II through the 1970s.  In 2011/2012 The Getty Center held an exhibition entitled Crosscurrents in L.A. Painting and Sculpture, 1950-1970.  One of the artists in the show was the painter Frederick Hammersley, who died in 2009.  After Hammersley’s death a artist-endowed Foundation was established to preserve and maintain his artistic legacy.  Getty researchers first encountered the extensive archive of materials held by the Hammersley Foundation during preparations for the Crosscurrents show.  Alan Phenix presented to the Paintings Specialty Group some introductory observations on the wealth of that information.

Frederick Hammersley was a leading abstract painter in Southern California in the postwar period.  He first gained widespread notoriety in 1956 when he was included with artists Karl Benjamin, Lorser Feitelson, and John McLaughlin in an exhibition entitled Four Abstract Classicists.  The show led to the coining of the painting movement known as “West Coast Hard-Edge”.  Hammersley was born in 1919 and studied art in the 1940s at the Chouinard and Jepson Art Institutes in Los Angeles.  He stayed on at the Jepson Institute in a teaching capacity after he finished his studies.  He also held subsequent teaching positions at Pomona College (1953-62), Pasadena Art Museum (1956-61), and Chouinard (1964-68).  In 1968 he took a teaching position at the University of New Mexico in Albuquerque, which he kept until 1971 when he stopped teaching to concentrate on his painting.  He continued to work at his home studio until six months before his death and his space remained essentially untouched after his death, serving as final documentation of his life and work.  Hammersley had also fastidiously documented his artistic process in series of notebooks for a period of more than 50 years with few interruptions.  Among the most notable of these were four “Painting Books” that consist of cumulative and descriptive chronological lists of works completed.  The project being undertaken by the Getty Conservation Institute aims to examine and interpret that archive of materials for what it may reveal about Hammersley’s process, materials and techniques, and what it might mean for the preservation and conservation of his work.

Hammersley’s painting had a strong psychological element, which is illustrated in the evolution of his work.  From 1954 to 1959 he worked on a series he called “Hunch” paintings, which developed without preparation as the artist relied on “hunches” coming from reflection and intuition to guide his work.  In 1963 until 1965 he worked on series defined as “Organics” and “Cut Ups” that expanded upon his intuitive painting with more organic processes.  In several periods throughout his career he also worked on more hard-edged geometric paintings.  An early instance of his documentation and creative evolution was found in a set of notes on labels on the back of a 1956 “Hunch” painting entitled In Front Of, in which he recorded dates for the addition of specific shapes in the composition.

The artist began keeping his “Painting Books” in 1959, wherein he kept lists of his work, information about his process, when and to whom each work was sold, and other related information.  The details of his records continued to increase and by 1966 he’d expanded his notes to include additional items, such as information on specific paints.

It was interesting to hear that Hammersley’s documentation was not limited to formal records and itemized lists; his notebooks were also works of art in their own way.  Some of his books contained visual composition ideas in thumbnail sketches.  When he liked a composition he would execute it in a slightly larger (ca. 3″ x 3″) format.  Eventually he began including sequential breakdowns of the development of particular artworks.  On occasion he would revisit past artworks and those changes were also documented in his notebooks.  The artistic process was not limited to the works themselves.  Hammersley kept a “Titles” folder that contained lists of words written by free association.  When he came across words he liked he would underline them and then retrofit them to create titles for particular works.

This presentation just scratched the surface of the available information in Hammersley’s personal documentation.  The goal of the Getty Conservation Institute’s work is to make the mass of information of Hammersley’s archive available to a wider audience, including conservators who may have cause to work on his paintings in the future.  A searchable database is envisaged once the material is transcribed, collated, and interpreted.

This year’s annual meeting was focused on connecting to conservation through outreach and advocacy.  A searchable database of artists’ materials and techniques certainly has potential to assist with that effort.

AIC’s 40th Annual Meeting – Paintings Session, May 9, “Relating Artist Technique and Materials to Condition in Richard Diebenkorn’s ‘Ocean Park’ Series” by Ana Alba

When Ana Alba was working at the Hirshhorn Museum she undertook a research project on four paintings from Richard Diebenkorn’s “Ocean Park” series.  Her study compared the materials used in each of the paintings and assessed how that tied in to their current condition.  She presented her findings at the 2010 annual meeting in Milwaukee, Wisconsin.  Two of the paintings had severe cracking while the other two were in good condition; the paintings with the cracking had an acrylic preparatory layer.  At this year’s annual meeting she presented research conducted at the National Gallery of Art that expanded upon her intial study.

Ana’s current research involved the examination of more than 45 paintings and samples for analysis were collected from approximately 15 paintings.  All of the information gathered was compiled into an extensive chronological database.  An additional list of travel histories with photographic references was completed.  The results of this study showed changes in the artists materials both between paintings and within individual works.

Diebenkorn worked for weeks to years on some of his paintings.  He painted consistently on unsized cotton duck but his choice of preparatory materials fluctuated over time.  Between 1968 and 1973 he used white acrylic gesso and toned it with diluted acrylic.  In some cases he added alkyd.  From 1973 to 1978 he transitioned from white to clear preparatory layers, presumably in order to maintain the raw canvas color and achieve transparencies in his paint layers.  Scientific analysis suggested the clear material was synthetic and consistent with Rhoplex AC-33.  This was more or less confirmed by photographic evidence of showing large jugs labeled as Rhoplex located in the artist’s studio.  By 1979 Diebenkorn had returned to using acrylic gesso almost exclusively.

Diebenkorn primarily painted with acrylics and alkyds.  He added oils sparingly and extended his paints as far as possible.  He also used charcoal, graphite, and colored pencil to define his images.  Infrared reflectography of his paintings show numerous alterations in his compositions, which is unsurprising given his appreciation of layering and the amount of time he spent working on each piece.  Once a painting was finished he applied matte fixative to the surface.  In his early works he applied this in 6 or 8 consecutive layers that left a glassy, heavy surface.  Eventually he shifted his process and masked out the painting to limit application to the charcoal areas.

The condition assessment of this larger group of paintings seem to support the findings of Ana’s initial study.  Paintings executed between 1960 and 1973 vary and some show some cracking.  The cracks follow drawn lines, compositional changes, and are greatest on the paintings with heavy layers.  Paintings completed after 1973 and before 1980 have heavier, more pronounced cracking with broad and isolated areas of cupping.  These paintings follow the same trend as the earlier works with the greatest cracking located in the layered areas.  Diebenkorn’s paintings after 1980 are in much more pristine condition with less cracks.  The trend of this condition timeline show that the paintings in the poorest condition are located in the middle of the Ocean Park series.  This supports previous findings by showing that paintings with Rhoplex and acrylic exhibit the worst cracking, especially when they are painted thickly with numerous layers.

This study highlights concerns regarding some of Diebenkorn’s selection of materials.  Alkyds are brittle so putting them over flexible preparatory films and unsized canvas makes them susceptible to cracking from impacts and physical movement of the substrate.  Fortunately, they do not seem prone to delamination so the cracking does not lead to significant paint loss.  In addition, when Diebenkorn diluted his materials he reduced their strength.  That left them with a greater chance of deformation in response to physical and environmental factors.

Ana pointed out that there are some limiting and extenuating factors to consider in this research.  The are as follows:

  • No samples were taken from privately owned paintings.
  • His assistants did not see him working so they could not provide information about his process
  • Diebenkorn did not keep detailed records of his work or do preparatory drawings.
  • The study compares paintings in good and poor condition only.
  • The artist destroyed some works, painted over others, and skipped #5 when creating the series.
  • One large painting from Brooklyn was an outlier in the study; it was completed prior to 1973 but it shows significant cracking across large ares of the surface.
During the question and answer session following the presentation it was also noted that areas with Rhoplex on raw canvas showed discoloration.
I have a personal appreciation for Diebenkorn’s work and have enjoyed following the progression of Ana’s research project.  By coincidence, I had the opportunity to realize that interest in person this week when the exhibition, Richard Diebenkorn:  The Ocean Park Series, was deinstalled at the Orange County Museum of Art in California.  I conducted outgoing condition assessments of some of the paintings and was able to see exactly what Ana had discussed in her presentation.  The exhibition will open at its final destination, the Corcoran Gallery of Art, on June 30th.  I encourage all of you to check out the show if possible to see the subjects of Ana’s research side by side for the first time on such a large scale.

AIC’s 40th Annual Meeting – Paintings Session, May 9, “Print or Painting? The Treatment of a Penschilderij by Willem van de Velde the Elder” by Kristin deGhetaldi

Penschilderijn*, also known as “penpaintings“, involve drawing an image in black ink on top of a substrate prepared with a white lead oil ground.  The technique originated in seventeenth century Holland and was popularized by one of its most skilled practitioners, Willem van de Velde the Elder.  The artist’s painting, Dutch Ships Near the Coast, became the first penschilderij in an American public collection when it was gifted to the National Gallery of Art in 1994.  Treatment of the painting began in 2010, which gave conservators the rare opportunity to conduct an in-depth study of the materials and techniques utilized in its creation.  Kristin deGhetaldi headed the treatment of the painting and presented the current study findings and treatment results to the Paintings Specialty Group.

Willem van de Velde the Elder built his career on pen paintings but his beginnings were much more humble.  He was born in 1611 as the son of a skipper and spent most of his early years on ships, giving him a natural familiarity with navigation and the sea.  He was also an excellent draughtsman and became skilled at sketching maritime scenes.  As his skill improved he was sought for victory images and his clientele of wealthy patrons increased.  He gained significant notoriety with his penpaintings as early as the end of the 1630s and it was said that his penschilderij were considered more popular and valuable than his other works.

Penpaintings were often done on panel or vellum primed with oil.  Working atop these surfaces with pen and ink made it difficult to make corrections to the composition.  Van de Velde was a perfectionist who was easily dissatisfied with the quality of his work.  If he did not like a sketch he would go over the basic outline in wet ink and quickly press the image to another substrate and begin again.  He also utilized both fine line drawing and washes to create his images, with washes becoming more prominent in his work by the 1650s.  Washes provided the advantage of covering large areas quickly without the need for intricate underdrawings.  This allowed the van de Velde workshop to generate larger penpaintings at a faster rate in order to meet teh demands of the market.

A visual analysis of Dutch Ships Near the Coast was conducted in comparison to van de Veldes other known works and some characteristics stood out.  Although it is dated to the 1650s, the work is smaller than his other penpaintings and it lacks the expected fluid washes in favor of fine linear strokes.  The penpainting does have an underdrawing, though it remains unclear whether it was sketched in silverpoint or graphite.  In addition, the ground layer composed of calcium carbonate instead of the slightly darker ground that is common in his similar works.  Finally, unique raised lines are present where the ink is applied and in other areas of the white ground.

Scientific analysis was conducted in an attempt to clarify some of these discrepancies.  Cross-sectional microscopy revealed two layers of lead white, with the topmost layer containing particles that were more finely ground.  The presence of only carbon black in the ink design confirmed that iron gall ink or bone black was not used by the artist.  Analysis using GCMS was conducted in an attempt to identify the binding medium of the ink, though the tests were inconclusive.

Conservators decided to create a reconstruction of the penpainting to gain insight into the identity of the oil binder and find possible causes for the raised lines.  Linseed oil was used in the reconstruction but it yellowed quickly, leading conservators to believe a slower drying oil was used in order to avoid the discoloration.  Next conservators tested reed and quill pens dipped in gum based ink to determine how the ink was likely applied.  Reed seemed like a good candidate but they produced broader and less precise lines than the sharp, fine lines created with quills.  Goose quills were ideal but quills from raven and crow feathers were also acceptable.  It was hypothesized that the sharp quills may have scratched the ground before it was totally dry and created the fine lines.  However, that did not account for the raised nature of the lines or the fact that they existed in areas where ink was not applied.  At that point conservators wondered if the lines could be the result of engraving techniques.

The Dutch artist Experiens Sillemans was a contemporary of van de Velde and also created penschilderijn.  Sillemans was known to use printmaking practices such as engraving in the creation of his works.  The technique involved pressing a freshly inked engraving on to a primed support.  To create raised lines, however, van de Velde would have had to press his inked copper plate into the soft preparatory ground of the support.  Given the art historical evidence, it still seems unlikely that van de Velde used this practice as no two of his penschilderij are alike.  In addition, there are no prints in his oeuvre to suggest he was a practiced engraver.

Ultimately the technical study of Dutch Ships Near the Coast left more questions than answers and conservators are hopeful that future study will lead to greater understanding.  At that point it was time to address the treatment of the piece.

Examination of the painting revealed fills and overpaint, discoloration, flaking, and crumbling around the fills.  The abraded surface was almost ghost-like in some areas and the face of one man in the foreground was completely lost.  The painting was stabilized using sturgeon glue.  During removal of the varnish layers, Kristin did not have to worry about solubility issues.**  Once the painting was given an isolation layer of MS2A varnish, losses were filled using a mixture of Aquazol 200 and Modostuc.  To begin the inpainting process Kristin  isolated the painting with MS2A and then used pigmented micropens under magnification to conduct a painstaking recreation of the abraded areas.  The damaged background was reinforced with thin HB micro graphite sticks.

A question and answer session followed Kristin’s presentation and someone asked what additional theories she may have regarding the cause of the fine lines.  Kristin said she has a few weak theories.  One theory is that the penpainting was put in the sun to bleach and dry, during which time the black ink may have absorbed more heat and created the lines.  Her second theory was that a slower drying oil like walnut or poppy may have left the grounds soft and created uneven drying which could have led to the raised lines.  She stressed that more study is necessary.

I thought this was a very interesting presentation and look forward to hearing about future developments in the study of Willem van de Velde’s penschilderij.



* A past study by David Freedberg, Aviva Burnstock, and Alan Phenix refer to these works as penschilderijen.  Since I am not fluent in dutch, nor an expert on penpainting, I deferred to the spelling used by Kristin deGhetaldi.

** The question of solubility was raised during the question and answer session, to which Kristin replied she detected absolutely no solubility issues in the materials of the penpainting, especially since the painting had already been subjected to harsh overcleaning in the past.

AIC’s 40th Annual Meeting – Paintings Session, May 9, “Treatment of Izhar Patkin’s ‘The Black Paintings’–Collaboration and Compromise” by Jennifer Hickey

Israeli-American artist Izhar Patkin’s work combines traditional painting and sculpture with nontraditional techniques.  In 1986 he completed his work, The Black Paintingsa series of twenty-two pleated neoprene panels painted with images based on Jean Genet’s play, “The Blacks: A clown show.”  The 14′ long panels hang side by side to create a 28′ x 22′ installation.  Recently, the sculpture and painting conservation departments at the Museum of Modern Art in New York collaborated to address the treatment of this work.  Jennifer Hickey presented the challenges, philosophy, and compromises of the project to the Paintings Specialty Group.

When conservators took on The Black Paintings they were met with a host of interesting challenges.  The first set of issues had to do with the materials.  Neoprene is a stable synthetic rubber that maintains its flexibility over time and wide temperature variations.  It is not an ideal substrate for painting because of its flexibility and the size and weight of each panel exacerbated that problem.  The artist was aware of those issues and used spray paint and vinyl paint under the assumption that the spray paint would crack while the vinyl paint would remain flexible.  Unfortunately, the expected interactions of the materials proved false as the entire painted surface cracked and flaked with the stretch of the neoprene.  The cracking and losses were compounded by the handling required to deinstall and reinstall the panels each time they were exhibited.

The physical incompatibility of the neoprene and paint media was not the only problem.  Neoprene is often coated with a talcum-based release agent to keep it from being sticky.  The application of the talc leaves a hazy gray surface that the artist liked so he painted on it without removing the coating or preparing the surface with another material.  Therefore, the release agent that kept the neoprene from being sticky also acted as a release agent for the paint media.

Conservators were also faced with challenges that went beyond the materials.  Izhar Patkin is a living, working artist so conservators were able to consult him during the assessment and planning stages of the project.  This may sound like a blessing if we consider all the times we’ve wished for input on a complicated project from its creator.  However, it can be a double-edged sword and that was the case with The Black Paintings.

As previously mentioned, Patkin was aware that the painted surfaces would deteriorate and enjoyed the nonstatic idea it presented.  He chose his materials to encourage that deterioration and scratched into the paint to initiate the process.  He also appreciated how the heat of the installation space intensified the smell of the neoprene.  Perhaps it was serendipitous that such heat adds to the risk of instability in paint films.  Conversations with the artist allowed conservators to understand where he’d intended damage and deterioration, which guided their treatment decisions.  At the same time they ran into complications during their discussions.  For example, the artist and conservators used the word “craquelure” to describe different phenomena and the conservators had to contend with impractical suggestions from the artist.

In the end the treatment of The Black Paintings was limited to triage with the understanding that maintenance treatment will be required each time the panels are unrolled.  Conservators designed a cleaning system that accounted for the sensitivities of the solvent based paints and avoided heat, which could have compromised the rubber.  The panels were hung and then gradually lowered to a table for access, at which point they were cautiously dry cleaned and a very time consuming consolidation was undertaken using an acrylic emulsion adhesive.  An old interleaving was replaced with finely woven undyed cotton and permanent cleats were secured to the tops of each panel.  At that point the panels were rerolled and stored.  A manual was prepared to instruct all individuals on the proper handling during all future installations and deinstallations.

This was a very complicated project that illustrated many of the issues that arise when dealing with modern and contemporary artworks and the involvement of a living artist.  A question and answer session following the presentation continued to highlight the gray areas surrounding these kinds of treatments.

One conservator asked Ms. Hickey why they chose to roll the panels with the paint side facing inward rather than out because of the added risk it posed to the already unstable paint.  Ms. Hickey explained that the size and weight of the panels necessitated this compromise because they were too large and heavy to flip over once the panel was unrolled.  Rolling them in this way may risk the paint but significantly reduced the level of handling and resulting unavoidable losses.

A second question posed to Ms. Hickey was whether or not they thought of alternatives to the permanent cleats because rolling the paintings with the cleats creates a risk.  When Ms. Hickey explained that the budget of the project would not allow other preferable but more expensive alternatives she was asked if they considered the fact that additional costs at present could maintain value in the piece and curtail future treatment costs.  Ms. Hickey addressed this question with great poise by reminding us all that conservators do not always have the final say when it comes to the cost of a treatment and sometimes we must find the best compromise available within our limitations.

This was an excellent presentation and I hope it will lead to continued discussions regarding the issues that arise in these kinds of complicated projects.

AIC’s 40th Annual Meeting – Paintings Session, May 9, “Challenges and Choices in Conserving an Early Abstract Expressionist Painting by Clyfford Still” by Barbara Ramsay

American painter Clyfford Still (1904-1980) was a leading Abstract Expressionist artist.  In November of 2011 the new Clyfford Still Museum opened in Denver, Colorado.  For more than seven years prior to the opening conservators in the ARTEX Conservation Laboratory worked to prepare Still’s paintings for travel and exhibition.  One of those paintings was the oil on canvas,  1943 (PH-286).  Barbara Ramsay carried out the treatment of the painting and kept coming back to the question, “Should we hold the artist accountable for the materials and techniques that he has used, or should we attempt to reintroduce aspects of his original intent as we perceive them?”   As one might expect, the answer is often complicated and open to interpretation.

1943 (PH-286) is a key early painting in Still’s oeuvre that serves as an excellent documentation of his artistic process.  The painting represents his transition from abstracted figurative work to the complete abstraction for which he is known.  It is understood that Still considered the painting to be an important work and he exhibited it more often than most of his other works.  The painting also important because it has the inscription “White and Black” on the verso, which may be an early title because he did not completely abandon titling his work until some time in the 1940s.

The stretched painting was executed on unsized cotton duck canvas with a white ground.  The canvas showed signs of being unstretched and restretched more than once.  It was slightly stained but otherwise it was generally stable.  Examination of the paint layers revealed mingling of matte and glossy areas and a discolored surface coating.  The areas of highest gloss appeared bluish white under ultraviolet irradiation but whether there was a local or overall surface coating remained unclear.  There were also areas of marked drying cracks in the black paint layers but all of the cracks appeared to be stable.

After minor consolidation, the structure of the painting was stable so the focus of treatment was on the aesthetic qualities.  Barbara’s approach was to open up a dialogue between curators, the representatives of the Still estate, and conservators to discuss the interpretation of the condition and determine a course of action that prioritized minimal intervention.  Unfortunately, such conversations are often complicated and this case was no exception.  Some of the stakeholders felt the painting should be left as is.  Others wanted the drying cracks to be inpainted.  Still others wanted a complete aesthetic treatment to remove and replace the discolored varnish, saturate the matte areas, and inpaint the drying cracks.  Barbara wanted to do more research before determining her ideal course of action.  The critical questions:  could it be done safely and should it be done at all?

To answer those questions Barbara focused on Still’s working process.  GCI analysis suggested that he used titanium white ground, zinc white, carbon black, organic colorants, and some commercial tube colors on his paintings.  Many of Still’s paints are known to be particularly sensitive to water and organic solvents.  The variable gloss in the paint surface posed several other issues for consideration.  The matte areas could have indicated an original difference in leanness in the paint.  It was possible that Still applied an overall surface coating that soaked into areas of underbound paint over time and left an unexpected variable gloss.  There was also a chance that Still applied the coating to specific areas of the painting.  So, did Still apply a coating?  Was it local or overall?  Did he intend or like the uneven surface?  Research turned up examples where Still did both localized and overall surface coating applications.  It was documented that paint that appeared “too dry” was not his original intention.  However, what did he mean by “too dry”?  Was this an “overly matte” surface or did it describe a surface that had traces of efflorescence?

Additional study by the GCI identified a drying oil on the surface and it was determined that Still likely coated the painting with the oil in the 1970s.  Examination under ultraviolet irradiation supported the theory that the oil coating was absorbed by leaner areas of paint, resulting in localized matte patches.  Although the oil was applied by the artist there was no documentation to indicate what effect he was trying to achieve.  Since the discolored coating was very disfiguring and misleading, it was decided that it should be removed.  But could it be removed?

As expected, solvent sensitivities in the paint layers complicated the removal of the surface coating.  As a result, it was determined that selective and partial cleaning was the most viable option.  Using solvent compresses the coating was reduced in the whites, grays and colored areas, but was left untouched over the black paint.  A varnish was not applied either to the cleaned areas or to the matte black paint passages.

The last step in the treatment was inpainting of the craquelure.  Barbara preferred to leave the craquelure as evidence of the artist’s materials and working methods but finally agreed to inpaint the most distracting craquelure with a reversible medium.  At that point the treated painting was ready for exhibition.

This was a complicated project full of the difficult questions that seem inherent in the treatment of modern and contemporary art.  As a result, the conclusion of Barbara’s presentation was followed by a very interesting question and answer session.  I was unable to keep a written record of the various dialogues that occurred but I can recall one question and answer that I thought was interesting and could lead to additional discussion:  One conservator asked Barbara why she decided to inpaint the craquelure when Still had chosen to exhibit it for so many years in that condition.  Barbara replied that she had considered this factor and believed it was a valid reason not to inpaint.  She did not want to inpaint the craquelure but she feared the other alternative was that the painting would not go on exhibit.  She felt it was necessary to compromise on inpainting the cracks to ensure that such an important painting would be included in the inaugural installation in the new museum.  She noted also that Still had not intended that the drying craquelure would form.  She felt the museum’s desire to show Still’s work to the public for the first time looking its very best was also a valid concern. What do you think?

AIC’s 39th Annual Meeting – Paintings Morning Session on June 3, “Industrial Literature as a Resource in Modern Materials Conservation” by Dawn V. Rogala

Artists working in the post-WWI era frequently used industrial products in their work.  This can put conservators in the position of dealing with materials with unknown compositions and behaviors that are not conducive to long-term preservation.  Unfortunately, existing conservation literature does not always provide adequate materials information or case studies for conservators wrestling with these issues.  Expanding literature searches to include period industrial articles can fill in those informational gaps.

Dawn Rogala discovered the benefits of such industrial literature while researching mid-century American oil-based zinc oxide house paint during her postgraduate fellowship at the Smithsonian Institution in Washington, DC.  Her research focused on a group of abstract expressionist paintings and the relationship between their zinc oxide grounds and failure of the paint layers.  She found that industrial literature provided significant evidence of a connection between the choice of materials and the current unstable condition of the paintings.

The period between 1925 to 1950 provided Rogala with the most useful articles, likely due to market demand and frequent product adaptation during that time.  The largest percentage of articles she found were presented by representatives of the paint manufacturers who were focused on promoting the benefits of their paint to consumers.  Those may seem like biased and unreliable sources for accurate information, however such articles often mentioned engineered mechanical behaviors that were considered beneficial in their paint films.  Approximately 25% of the articles in her research were affiliated with scholarly research.  Those articles provided more comprehensive and practical analyses of paint film behaviors with useful reference bibliographies.

Weathering test articles were another rich source of information on paint formulations and behaviors.  The variations in regional weather often caused adaptations in regional paint formulations.  This meant that artists working with a zinc oxide house paint in a mild climate may have worked with an entirely different formulation of zinc oxide house paint than an artist working in a more severe climate during the same period.  It also suggested titanium dioxide’s introduction into house paints in the mid-1950s could have been delayed on a global scale when considering issues of climate influences on formulation changes.

One of the specific examples Rogala gave to illustrate the usefulness of industrial literature referred to self-renewing paint films.  Weathering test articles cited a preference for acicular particles because their brittle nature allowed for microfissures in the paint, which would cause it to slough off in the rain and result in a crisp clean surface.  Another example was the mention that three years was the required life expectancy for engineered paint films according to industrial standards.  While such qualities were acceptable and even desirable in house paints, such paint films pose clear disadvantages for conservation.  In fact, Rogala pointed out a 1909 article that warned about the dangers of zinc oxide paint as a ground layer!

I thought this was an outstanding presentation.  Conservators must be resourceful and adaptable when dealing with unknown, unpredictable materials.  This is a particular necessity when it comes to the conservation and preservation of modern and contemporary artwork.  I appreciate Rogala’s study for delving into the industrial side of zinc oxide and providing an open look at a somewhat unconventional resource for conservation research.

AIC’s 39th Annual Meeting – Paintings Morning Session on June 3, “The Construction and Reconstruction of the 15th Century Spanish Retable” by Judy Dion

Judy Dion’s study of 15th-century Spanish retables adds to the limited information available on the impressive altarpieces that have undergone less technical and historical research than their Northern European and Italian Renaissance cousins.  Dion’s research is the result of five years of collaborative efforts during her Mellon Fellowships at the Balboa Art Conservation Center and the Philadelphia Museum of Art.  The study involved extensive non-invasive examination of panel paintings from the collections at the San Diego Museum of Art and Philadelphia Museum of Art, as well as paintings in Spain, the United States, the United Kingdom, and mainland Europe.  Dion focused her investigation by concentrating on panel paintings made in the Spanish regions of València, Catalonia, and Aragón. Her findings address construction methods specific to Spanish retables, how construction features on individual or smaller sections of panels can provide clues to their placement within a complete retable, and the history and changing attitudes regarding alterations of disassembled panels.

To summarize the discussion of construction, retables consisted of a central panel surrounded by additional panels usually in the form of an inverted T-shape that measured anywhere from two to seven meters high.  The panels were in a fixed position and surrounded by framing components that served as pictorial and transitional elements between the scenes.  Review of the fabrication methods showed the panels, most often constructed from poplar or pine, were assembled using butt-joined boards with battens.  Transverse battens were used in combination with either vertical or diagonal battens but the latter were never used together.  All of the retables from the Valencia region examined in Dion’s study had diagonal battens and metal dowels were common additions.  Any flaw in the panels were filled with wooden shims and gesso before painting commenced.  Nonwoven plant fibers and fabric were also used in preparation of the panels.

In my opinion the most interesting part of the construction was during the assembly step that included the framing elements.  The frame components were attached to one of any two adjacent panels and then overlapped the face of the second panel. Raised framing elements were installed during the final assembly.  This construction caused a bare edge and gesso burr on the side of the panel with the attached framing element, while the paint layer extended to the edge of the side that was overalapped.  As a result, individual panels often appeared asymmetrical when retables were disassembled.

The disassembly of retables was often a response to changing aesthetics, demand for profit, and damages.  Individual or smaller panel sections could hold a higher value than an intact retable.  This led to frequent alterations of the panels to improve their appearance as stand-alone works.  Such alterations included but were not limited to repainting, the addition of false elements, and cutting down of the panel edges.  Fortunately, shifts in the methodology of collecting institutions encourage the recognition and appreciation of the historical context of fragmented works.  Panels that were altered for the aforementioned reasons are increasingly the subjects of reversal treatments.  In some cases the alterations are left visible, while in others missing or altered elements are restored to recover evidence of their original appearance.

This is a very abridged overview of Judy Dion’s thorough research and presentation due to my mere mortal status as a note taker.  I encourage anyone interested in this subject to seek out the conference postprints and/or approach Ms. Dion with any questions regarding her study.  She applied her findings to a hypothetical reconstruction of Jaume mateu’s The Birth of the Virgin, from the John G. Johnson Collection at the Philadelphia Museum of Art.  It is an excellent case study and definitely worth a review to gain a greater understanding of this research.