This talk was given by Sarah Bertalan, as the culmination of a career observing foxing and reverse foxing during her conservation practice. It is such an interesting topic that there was too much information to squeeze into 30 minutes, and Bertalan left us hanging without a conclusion but I will provide some links to articles that she mentioned at the end of the talk summary, as well as to the conservation wiki on foxing. I hope that she will publish in the BPG Annual Postprints, as I’m sure the majority of the attendees of her talk would agree! It is a topic that I find so interesting, and I even compiled my own literature review of foxing while in graduate school!
Bertalan’s observation of 19th and 20th century papers has led her to propose that foxing, the “reddish, brownish, roundish stains that occur in a random pattern,” is not caused by mold or by metal inclusions, but rather by inorganic additives that were added to the paper. It is widely reported that treating foxing stains can frustratingly lead to their reappearance within a relatively short amount of time. Bertalan also considers the capacity for 19th and 20th century papers to discolor over their entire surface, not just in in the staining we associate with foxing. In such cases, the stains may be extensive but superficial, and the condition would be due to contact with catalyzing, acidic materials, not migration of degradation products, as is seen for matburn. Reverse foxing is a term that remains undefined, and the cause is unknown. White spots, as if negative images of the dendrite-like reddish brown foxing spots, will appear and be visible in normal light, often after a paper has been treated. Reverse foxing has been identified frequently on Van Gelder Zonen papers.
Inorganic additives were added to papers in the 19th and 20th centuries to achieve specific results. Additives such as minerals and metal oxides were added to modify the surface and texture, to act as fillers and opacifiers, brighteners and to aid in ink retention. The additives are extremely reactive and act as salts, catalyzing acid-base reactions. While foxing was not visible immediately after the paper was made, elevated humidity, changing pH and daylight would provide the environment to form foxing. Contemporaries were aware of the effect of humidity on papers, notably the appearance of foxing stains.
Bertalan observes that the sensitivity of papers coated or immersed in metal salts to light is well documented, as the earliest photographs were made with paper coated in metal salts. The supporting evidence Bertalan presents for inorganic particles causing foxing is the presence of opaque zones that correspond to foxing stains when paper is seen in transmitted light. Furthermore, when foxing is not visible in normal light, opaque dendrite-like inclusions in the paper can be seen in UV light as well as transmitted light. Even when the reddish-brown stains have been washed out of the paper, the opaque regions still remain when viewed in UV light.
Resources:
http://www.conservation-wiki.com/wiki/Foxing_(PCC)
Soyeon Choi Literature Review on Foxing (you must use your AIC sign-in to access the article) http://www.maneyonline.com/doi/pdfplus/10.1179/019713607806112378
Browning, B.L. Analysis of Paper 1977.
Category: Specialties
AIC 43rd Annual Meeting – The Daguerreotype Uncovered: An Overview of the Surface and Subsurface Chemistry, Physics and Material Science Underlying the First Photographic Process Based on Electron Microscopial Studies. Patrick Ravines
This presentation was delivered by Patrick Ravines, Director and Associate Professor, Buffalo State University. Co-authors include Peter Bush, Lisa Chan, Natasha Erdman, Lingjia Li, Rob McElroy, and Anne West.
Patrick et al have been using electron microscopy to investigate the surface and subsurface of daguerreotypes. They have created fresh plates for the investigation, and have used these analytical techniques during each stage of preparation. They have made discoveries including how scratches to the surface Ag are not always completely removed during the polishing process, polishing removes approximately 1 mm of Ag, and fuming with I2 creates a discontinuous layer of AgI across the plate. One interesting thing Patrick noted was how upon placing a sensitized daguerreotype plate in an SEM, the electron beam produced enough energy to cause the AgI particles to print out before their eyes. After exposure to Hg vapor, they were able to observe the Ag-Hg particles from various angles and discern that there are many other cluster shapes than cubic and hexagonal. Using lasers, they drilled into the daguerreotype surface, created cross-sections, and observed the subsurface voids. Patrick discussed their believe that the subsurface voids are the result of Ag migrating up to the surface to form the image material, leaving behind an absence of material. This work will be published soon in more detail.
Patrick noted that professionals in the electronics industry are using similar materials, Ag and Au, and they are finding similar subsurface voids.
AIC 43rd Annual Meeting – A Glimpse from the Dawn of Photography: Investigation and Stabilization of an Early Daguerreotype from 1839 at the Peabody Essex Museum. Elena Bulat and Kathryn Carey
For this presentation Kathryn Carey, paper conservator at the Peabody Essex Museum (Massachusetts), introduced the project and the museum. The Peabody Essex received an early daguerreotype dated 1839 from a donor in 1858. The image is of Pont Neuf in Paris, and the plate is tentatively attributed to Vincent Chevalier, or Daguerre himself. The daguerreotype was “rediscovered” in 2008 and Elena Bulat, photograph conservator at Harvard University’s Weissman Preservation Center, was contracted to perform analysis and treatment. The daguerreotype was housed in the European style with a paper passe-partout and framed. Elena’s work consisted of opening the package, digitally imaging the plate, performing XRF on the plate and FTIR on the glues, fiber analysis of the papers, observation and imaging under UV radiation, removal of superficial dust from the plate with a manual air blower, replacement of the old passe-partout and cover glass with new but similar materials, and rebinding. XRF revealed low levels of Hg and no Au. S was found in tarnish areas, and no Cl was found. These results in conjunction with observation under UV confirm the identification of this plate as an early 19th century daguerreotype that was cleaned. FTIR revealed beeswax, and fiber analysis found bast and cotton fibers in the paper components. The new housing for the plate consisted of a backing piece of borosilicate glass, a window mat of borosilicate glass, and a new cover glass (also borosilicate). The plate was secured between these layers with a mylar Z-tray. Elena recommended the plate not be exhibited as it was not stabilized by gold toning.
Elena described her experience speaking with a reporter from the Boston Globe regarding this project, and how he had difficulty grasping the concept that “treatment” does not necessarily mean intervention. This rang true for me, and I imagine for many other conservators in the audience. You can read the article here: http://www.boston.com/ae/theater_arts/articles/2010/06/27/a_glimpse_from_dawn_of_photography/
43rd Annual Meeting-Book and Paper Session, May 15, 2015, "16-17th Century Italian Chiaroscuro Woodcuts: Instrumental Analysis, Degradation and Conservation" by Linda Stiber Morenus, Charlotte Eng, Naoko Takahatake, and Diana Rambaldi
The presenter, Linda Stiber Morenus, began her discussion of these complex prints with a description of the printing process. Chiaroscuro woodcuts were intended to emulate chiaroscuro drawings, which were comprised of black chalk shadows and white chalk highlights on colored paper. Color oil-based printing inks were first used to print 14th-century textiles, being used on paper by the mid 15th-century. The chiaroscuro woodblock prints required two to five separate woodblocks, inked with different shades lighter and darker than the midtone colored paper.
In order to better characterize the media, Morenus collaborated with art historian Takahata, and conservation scientists Eng and Rimbaldi from the Los Angeles County Museum of Art (LACMA). In addition to prints at LACMA, the team studied prints from the British Museum and Library of Congress. Out of over 2000 surveyed woodcuts, 72 were studied in depth, with X-ray Fluorescence (XRF), Fiber Optic Reflectance Spectroscopy (FORS), and Raman spectroscopy. Inorganic compounds were indicated by XRF analysis. FORS was especially helpful for detection of indigo. Raman spectroscopy provided additional information about organic colorants.
Renaissance artists’ manuals, such as Cennino Cennini’s Libro dell’Arte guided the research by providing information on the most likely colorants for printing inks. Inorganic pigments included lamp black, lead white, ochres, vermillion, verdigris, and orpiment. Organic pigments included indigo and a variety of lake pigments.
After providing background information, the presenter began to focus on deterioration and conservation of the chiaroscuro prints. The prints from the Niccolo Vicentino workshop had a high lead content. The inks typically had a low vehicle-to-pigment ratio, tending to turn gray around the edges, due to the presence of lead sulphide. Verdigris corrosion was also a common problem, as found on “Christ Healing the Paralytic Man” by Giuseppe Niccolo Vicentino, as well as 13 other prints from the same workshop. Typical copper-induced paper degradation included yellow-brown halos around inked areas and cracks in the paper.
Fading and discoloration were major problems for the organic colorants, such as indigo and the yellow lakes. Morenus compared copies of Ugo da Carpi’s “Sybil Reading a Book” in the British Museum and the Library of Congress, finding clear evidence that the indigo in the British copy had faded. The British Museum had confirmed the presence of indigo through Raman spectroscopy. At least 8 of the prints were found through XRF to have high levels of calcium in the same areas where indigo had been identified, suggesting the presence of chalk-based lakes. Organic greens had shifted to blue or brown where organic yellows had faded or become discolored.
The presenter concluded with suggestions and caveats for conservation treatment. First, she advised conservators to exercise caution in aqueous treatment, in order the preserve the topography of the prints. The woodblock creates a relief impression in the paper, and the layering of the inks adds another level of texture that might be altered by humidification, flattening, washing, or lining treatments. The low binder content also makes the inks more vulnerable to saponification and loss during alkaline water washing. Morenus warned that the hydrogen peroxide color reversion treatment for darkened lead white would be particularly risky, because the white lead sulphate end product has a lower refractive index than basic lead carbonate original pigment. This means that treated lead white becomes more translucent, and the lower “hiding power” shifts the tonal balance of the print to appear darker overall.
For exhibit recommendations, Morenus suggested that we should always expect to find fugitive organic colorants in chiaroscuro prints, so exhibit rotations should be planned accordingly. Maximum exhibit conditions should be 5 foot-candles (50 lux) of visible light for 12 weeks of exposure, no more often than every three years. She also indicated that overmatting should be avoided to reduce the risk of differential discoloration.
During the Question and Answer period, Morenus clarified the color order used in printing. Some prints were inked from dark to light, but most were printed with the lightest color first.
I thoroughly enjoyed learning about these beautiful prints, but I think that the discussion of the lead white conversion treatment-induced refractive index shift was the most important “take-away” from the presentation.
British Museum, 20-21st April 2015. Symposium on the care and conservation of human remains with a focus on natural mummies.
How comfortable do you feel surrounded by skeletal remains and natural mummies? The symposium hosted by the British Museum left no areas unturned, from the excavation, conservation and curation of natural mummies, and allowed participants of the day access to natural mummies from their extensive collection.
Daniel Antoine, curator of physical anthropology at the British museum, kicked the day off by considering the legal aspects and ethics in the curation of human remains. A huge 91% of the British population appears to be on side with the display and retention of human remains by museums for research purposes, but there are obligations. The display of human remains less than 100 years old does not sit well on some peoples’ shoulders and named remains attract a similar apprehension. This seems at odds with the display of Egyptian mummies that often have their names inscribed on their cartonnages, but maybe the longevity of these mummies makes their display more palatable.
Derek Welsby, assistant keeper in archaeology of Sudan and Egyptian Nubia, and Daniel Antoine followed with a description of the problems involved in the excavation of skeletal remains and natural mummies from their resting places, in this instance, the fourth cataract of the Nile Valley, Sudan. Skeletal remains dating back to the Neolithic period were uncovered from various burial sites and natural mummified bodies from the medieval period were excavated from this previously understudied region of The Sudan. Over a 1000 skeletal remains and naturally mummified bodies were donated to the British Museum by SARS, the Sudan Archaeological Research Society via the National Corporation for Antiquities and Museums of Sudan. For the past two years the British Museum have been undertaking research into population genetics and the pathology of these Nilotic human remains. A human remains database has been created by the museum that will open up the research potential of these people, negating the need for physical interaction and reducing the risk of damage to the bodies.
Barbara Wills, conservator of organic artifacts at the British museum had the job of surveying the mummies. She examined, photographed, assessed the needs of each individual and established a strategy for stabilization. Barbara was in the wonderful position of receiving a Clothworkers Conservation Fellowship that allowed her to put all of her time and effort into the development of a passive method of stabilization and display. Barbara has a wonderfully calm demeanor that exudes respect for humanity. I don’t know whether she had this disposition before she started work on the mummies or whether the mummies taught her this respect on her travels with them. A workshop on the second day of the symposium allowed for the exploration of these stabilization and display methods that Barbara developed during her fellowship and shall be discussed later.
The life of the Nilotic people is unraveled not only from research into the human remains but also by analyzing the textiles and leather excavated along side the bodies. Caroline Cartwright, from the department of conservation and scientific research at the British Museum, gave an excellent talk about the problems and pitfalls of trying to identify materials that may have been in close proximity to soft tissues and Anna Harrison, a senior conservator of organic materials at the British Museum, followed with the issues surrounding the conservation of archaeological textiles. Of particular fascination was the discovery of human hair mats that were treated like dry archaeological wool and the revelation that an imprint of a textile may be present on a skin sample even if the textile no longer remains.
A lunch break allowed time for a visit to the temporary exhibition: Ancient Lives, New Discoveries, where a number of the curatorial issues discussed in the morning session could be seen in practice. The use of explanatory and contextual information was well presented and tasteful lighting within display cases offered respect to the mummies.
Nancy Odegaard from the University of Arizona and Arizona State Museum resumed proceedings by discussing the post-excavation deterioration of the Chinchorro mummies of Arica, Northern Chile. The storage facility for the mummies is far too hot and humid and the mummies are acting as the environmental buffer. Deterioration was manifesting itself in the form of a ‘black ooze’ emanating from the bodies. A quick, easy and inexpensive solution to this problem was the introduction of some locally sourced hygroscopic wall coverings that took over the work of attempting to stabilize the environment.
A Sudanese mummy offered Joanna Russell, from the department of conservation and scientific research at the British Museum, the opportunity to use HPLC to investigate the dyes present in colourful textiles adorning the body. All dyes identified, Pseudopurpurin, Purpurin, Alazarin and Indigotin were used in Egyptian dying.
Marie Vandenbeusch, a project curator in the department of Ancient Egypt and Sudan at the British Museum, used infrared reflectography on a tattoo found on the upper leg of a naturally preserved female mummy from medieval Sudan. The tattoo represents one of the earliest known surviving examples of a tattoo from this period and region and represents a Christian monogram of the Archangel Michael. (images found at: http://blog.britishmuseum.org/2014/06/26/tattoos-in-ancient-egypt-and-sudan/) Of particular interest was the fact that it was mainly women that were tattooed and this particular tattoo was hoped to provide protection under Michael, the patron saint of Nubia.
Heather Bonney, a collections manager for human remains and repatriation at the British Museum, discussed the general curation and digitization of the human remains collection at the British Museum. Human remains can be acquired via three different routes. They may have been purchased anatomical specimens, ethnographic collected remains or they may be from an archaeological context and each requires different legal documentation for their storage and display. Osteoware software and the Oracle Word database were then discussed for the digitization of the collection. (The Oracle Word database is really tailored towards a British archaeological context).
Finally but certainly not least Emily Taylor and Simon Prentice, museums assistants at the British Museum, gave a superb talk about the safe packing and transportation of human remains. It is essential that all remains are carefully photographed before travelling so they can be referred to after unpacking and the person unpacking the remains must be able to deconstruct and replicate the packing easily so it must be simple but effective. Cellite honeycomb boards were used instead of the old-fashioned mummy boards but beware, do not use the Aluminium version of the boards if the mummy is to be sent for a CT scan as the Aluminium interferes with the scan.
Barbara Wills lead the second day of the symposium. She gave us an insight into the development of an inexpensive, simple, reversible, reliable and relatively quick way of displaying human remains for display or research using Plastazote LD33 and LD45 (polyethylene foam), PTFE tape and sheets (polytetrafluoroethylene, plumbers tape) and Polyester wadding.
Plastazote LD45 covered in Tyvek (a spun bonded olefin material that is inert and gas permeable) can be placed on a cellite board onto which the mummy can be displayed. Plastazote LD33 can be cut into shape and pinned to the board, offering support or preventing movement.
Fig. 1 Artificial bones being supported or held in place by Plastazote LD33.
There should be at least a 10cm boarder to the outside of the human remains to prevent damage to any delicate parts when being transported. Barbara demonstrated a quick and easy way of cutting the plastazote into shape using only a big sharp knife. (Figure 2)
Fig. 2. Fold the strip of Plastazote LD33 and cut on the outside of the fold. Cut as deeply or as shallow as needed to create the supporting structure.
The wonderful thing about PTFE is that it adheres to itself through static attraction only. There is no adhesive involved! PTFE sheet can be wrapped around Polyester wadding that has been fluffed, to create really soft ‘pillows’. Really soft ‘pillows’! ‘Pillows’ of the size and shape you require. (Figures 3 and 4)
Fig. 3. Barbara Wills demonstrating the construction of a small PTFE and Polyester wadding ‘pillow’ used for the support of a very fragile part of a body.
The PTFE polyester wadding ‘pillow can be pinned directly to the board or supported in a cut piece of Plastazote LD33 to give extra support. This was named ‘The Mushroom’.
Fig 4. Barbara Wills demonstrating the construction of a skull mount using fluffed Polyester wadding wrapped in PTFE sheet. Barbara made a sausage shape that she then curved round and pinned in place. Plastazote LD33 cut into wedge shapes can be pinned at each pole position to offer additional support.
A sheet of PTFE could be pinned to a Plastazote LD33 surround creating a hammock like structure. This could support very fragile parts of a body that would not survive using a conventional support.
PTFE tape can be wrapped directly around a fragile part of a body that needs to be held together and, as there is no adhesive involved it is completely reversible. When the static property of PTFE could potentially be damaging to a fragmented part of a body or where hair is present then the static can be eliminated quickly by shooting a beam of electrons at the material from an antistatic gun. Conventional tying can then be used to hold the PTFE in place.
Barbara Wills was apologetic to those attending the workshop as she considered her ideas simple. However, the simple ideas are sometimes the ones that are overlooked and missed. Barbara has developed a system that can stabilize and display any human remains without the need for chemicals and consolidants. The mummies we observed had been displayed in a manner that negated the need to move them for research purposes. However, if a research project did come along that required the movement of any of the bodies then this could be easily achieved without too much intervention, minimizing any damage that might occur to these priceless human remains.
Author: Julie McBain, MSc student at Cardiff University.
Photographs: Renata Peters, Lecturer, University College London
2015 Annual Meeting EMG/OSG/VoCA Joint Session: Collaboration with Artists in the Preservation of Artistic Heritage
The Electronic Media Group (EMG) and Objects Specialty Group (OSG) of the American Institute for Conservation (AIC) are joining with Voices in Contemporary Art (VoCA) to present a special joint session on the topic of collaboration with artists at the upcoming AIC Annual Meeting in Miami, FL, May 13-16, 2015.
Recognizing that artists have a stake in the legacy of their work has shifted conservation practice in recent decades. Moreover, it is possible to maintain a critical art historical discourse while also integrating the voices and opinions of the artists within preservation strategies for their artworks. The mission of organizations like VoCA has been guided by the possibilities of this shift. Increasingly, these practices are flourishing at major museums across the country.
Many conservators are actively seizing opportunities to interview and otherwise interact with artists. This session provides a venue for novice and experienced practitioners alike, from conservation and allied preservation-related fields, to share their outlook on and practice of collaboration with artists and their associates.
The sessions will be take place on Thursday, May 14, from 2pm-5:30pm, and Friday, May 15, from 8:30am-12:30pm. A ½ hour discussion will be held at the end of each day’s talks, led by Jill Sterrett on Thursday and Glenn Wharton on Friday.
The full schedule for the joint sessions is available here.
PMG Winter Meeting – “New Insights into the Composition and Permanence of the Silver-Platinum Satista Paper and the Satista Prints of Paul Strand” by Lisa Barro
Lisa Barro covered new technical information about Satista paper and related topics on preservation of Paul Strand’s Satista prints at The Metropolitan Museum of Art.
At the beginning, Barro introduced Satista paper and informed the audience that the current research is building on the previous research presented at the 2003 PMG Winter Meeting, San Juan, Puerto Rico and published in Topics in Photographic Preservation, Volume 10: Lisa Barro, The Deterioration of Paul Strand’s Satista Prints.
Satista is a silver-platinum paper introduced in 1914. It was a cheaper alternative to platinum, before palladium paper was introduced. The Strand prints on this paper at the Met show overall fading and discoloration as well as local staining. Barro mentioned that there is a slim chance that the prints under study are platinum-toned barytaless silver paper rather than Satista, but this is unlikely, based on historical information about Strand’s papers. She also mentioned that it is unclear whether or not the Satista paper itself is causing this type of deterioration. It might be that just this group of prints that Strand made is deteriorating in this way, due to the processing, storage history, or other variables. It is possible that there are Satista prints in collections in good condition, perhaps presently identified as platinum prints. Further study and more XRF data will help make those determinations.
As part of the research published in Topics in 2003, Barro concluded that the deterioration was related to sulfiding combined with finely divided silver particles and staining possibly related to residual chemistry, but there have been many questions raised by this research. Some of these questions were related to characterization of Satista paper:
- Does Satista paper have what is called a Japine surface?
- Was there bromine in Satista paper, because the patent mentioned bromine in addition to chlorine?
- Some historical literature mentions gelatin, so is it possible that there could be gelatin present as a sizing or binder?
Conservators who heard Barro speak at PMG in 2003 have since asked her practical questions related to preservation:
- Should we exhibit these prints?
- How quickly are they changing?
- How sensitive are these prints?
This talk addressed these questions by sharing new findings from analyzing 15 years of spectrophotometric data collected from Paul Strand’s Satista prints before and after exhibition, as well as performing analysis on an unprocessed Satista paper with a range of techniques: transmission FTIR, ELISA, SEM-EDX, Raman spectroscopy and XRF. (The pack of unprocessed postcard-sized Satista paper was a gift from photographer Alison Rossiter in 2010.)
In general, the analytical results of this study shed some light on the questions above. The study showed no gelatin or bromine in the Satista paper. The question about the Japine surface is as yet unanswered; whether or not Satista has a parchmentized surface is still being investigated. If it does, it is thinner than observed in other prints. Barro also showed SEM images that illustrate where the silver and platinum salts are situated in the unprocessed paper in cross-section (the silver to platinum ratio was 12.5:1), but the implications for processed prints are not yet known. While analyzing the unprocessed Satista paper provided valuable information, it is possible that there were different surfaces made by the Platinotype Company.
To answer the questions related to exhibition and change in the prints over time, they used spectrophotometric data collected over 15 years at the Met. Color monitoring of the photograph collection at the museum began in 1992. Dana Hemmenway conducted a baseline study in 1999, and today the museum continues to collect data before and after exhibition to learn more about change during exhibition and storage periods. Katie Sanderson is the primary collector of this data at the museum. She takes measurements before and after exhibition in Dmin, Dmid and Dmax areas and evaluates the data using the CIE L*a*b* color space. Barro presented the findings that the overall rate of change for Satista prints is higher than for platinum, both in storage and on display. Using data for Strand’s portrait of Harold Greengard as illustration, she also demonstrated that the rate of change is measurably faster under exhibition conditions than during periods in storage. This data is still being interpreted and studied, and some data (such as different directions of change in different areas of the print) is posing new questions. Research is ongoing, but based on these findings, the study suggests that the approach to exhibition of Satista prints should be conservative. They recommend 40 lux, a sealed package, cool storage, and color monitoring.
PMG Winter Meeting – "Characterization of Digital Output Media… Or How to Hit a Moving Target" by Monique Fischer, Feb. 20
During the first day of the meeting, Monique Fischer, senior photograph conservator at the Northeast Document Conservation Center (NEDCC) gave a talk on her research on the characterization of digital output media. In 2010 Fischer was awarded a Getty Conservation Institute (GCI) guest conservation scholar position to conduct this research and although five years have passed since she started this work, the big picture concepts still remain relevant.
As photograph conservators know, many of the challenges associated with the preservation of digital output media are a result of the rapid development of technology and changes in product manufacture; in some cases materials have become obsolete, their formulations have changed, or their product name has changed. Due to these factors, the importance of gathering the “now” information was emphasized in the talk. This “now” information includes the collection of characterization data (type of paper, surface qualities, and component materials) from unused paper samples.
The impetus for this research project came in 2008 when Fischer noticed yellow stain formation on inkjet papers that had not yet been used. The sheets of inkjet paper were left in ambient conditions for about a year, and were only exposed to indoor air pollutants and some light; the uncovered areas of the paper showed signs of the yellow staining. In the talk, she noted other examples of yellow stain formation seen in different brands of inkjet papers: from consultations with artists as well as firsthand with the digital imaging department at NEDCC. In the latter instance, the staining occurred where the non-archival plastic packaging was in contact with the paper, prior to it being unwrapped. An important factor connecting the papers exhibiting yellow stain formation is that all possessed no optical brighteners (OBAs), and it is known that OBAs, a fluorescent component added to improve sheet brightness, may yellow when exposed to light and heat.
The research project had two major objectives: the creation of a digital paper characterization database and material analysis of paper samples. For the database, 241 paper samples were compiled and they are categorized to include: manufacturer and commercial name, thickness and weight, base substrate and composition, surface texture and finish, presence of OBAs, ink compatibility, and type of coating. Out of this, trends were documented, for instance, 81% of photographic inkjet papers contained OBAs, while only 31% of fine art inkjet papers contained OBAs. Additionally, OBAs were found in different layers of the inkjet papers.
Prior to looking at trends, Fischer notes the importance of using proper nomenclature for these materials. Part of her research includes the development of standardized terminology and she has turned to product discussion groups for photographers and practitioners using these different types of materials in order to gain insight on their current use and application. Though it is apparent that due to the proprietary nature of these materials, characterization may prove challenging.
The material analysis was carried out in conjunction with research scientists Dr. Dusan Stulik and Art Kaplan of the GCI. Initially, Fourier transform infrared spectroscopy (FTIR) was applied as a surface only technique, but due to limited sensitivity, minimally-destructive samples were taken. The findings from one type of inkjet paper were discussed, and in this paper sample, polyvinyl acetate (PVA) and a wax-like material as a possible coating and additive, respectively, were found.
Based on this finding, it was concluded that some coatings on inkjet papers may be PVA, a material widely used in many industries including the paper manufacture industry. In conservation, PVA has been documented as a relatively stable resin, and it is used for certain treatments in book conservation. However, it is possible that the stability of the resin is decreased when combined with additives – thus the yellow stain formation could be a result of degradation in the PVA coating. No conclusions were made on what caused the staining. Additional research goals include conducting gas chromatography/mass spectrometry (GC/MS) as a characterization technique.
Though not fully discussed in the talk, during the question and answer session, a question was asked regarding the impact of the printer profile on the stability of the inkjet print. Without hesitation, Fischer stated that the printer profile may have a tremendous impact on image permanence, specifically in color rendering and amount of ink used when using a manufacturer’s recommended printer profile or a custom printer profile. The main takeaway from her answer is that conservators should do their best [through artist interviews/consultations] to document as much information on an inkjet print including: printer profile, printer, type of paper, type of ink, et cetera, as these factors and their, potentially endless, combinations will greatly impact image permanence.
PMG Winter Meeting – “Photographic Paper XYZ: de facto standard sizes for silver gelatin prints” by Jennifer McGlinchey Sexton, Feb. 20
Jennifer McGlinchey started her impressive talk with an explanation of the history of lists of photographic paper sizes. She stated that there were no available references that have lists of ‘standard’ sizes. In fact, the lists of sizes they were able to find were very small, and also corresponded to very specific time periods. Further research suggests that these sizes were not considered standard and were certainly not inclusive of all sizes used. Rather than identify ‘standard’ sizes, she identified ‘common’ sizes by the criteria that they appear in five or more of the references. These she concluded were ‘de facto standard sizes.’ For the study, McGlinchey used Paul Messier’s extraordinary paper collection which consists of over 5,000 samples of silver gelatin photographic paper, as well as 9 manufacturer’s sample books and pricelists and 6 encyclopedias: http://www.paulmessier.com/
The use of English-language publications from a few geographic locations (US and Europe) may have been limiting, but in fact, there are very few references from other geographical areas. Concluding that there were common rather than standard sizes is not to say that there were no attempts to standardize paper sizes, but the attempts were never very successful. The result of the study was that she identified over 200 distinct sizes, just over half of which occurred only once. She identified 32 de facto standard sizes. Many of the sizes considered common now in the USA, such as 4×6 and 5×7 inches, are included in that list, but many sizes which are no longer manufactured are also on that list. This includes smaller sizes like 2.5 x 2.5 inch, which were much more common in early days of gelatin silver printing. She mentioned that the measurements for papers grouped together as the same size allowed for a difference of +/1 5 mm along each dimension, to account for natural expansion/contraction, ferrotyping, and so on, which could account for small dimensional changes. As part of the research they also evaluated common thicknesses of silver gelatin paper, and found three de facto standards. The most common was ‘single weight,’ followed by ‘double,’ and finally ‘medium.’ Double weight papers fall above 0.25 mm, medium weight papers under 0.25 and single weight papers under 0.2 mm. The double weight paper started get thicker in the 1930s until the 1950s and then got thinner again, so manufacturers changed the thicknesses over time but not the terminology. It was also found that five common aspect ratios occurred in 88% of the de facto standard sizes. This implies that scaling relationships were a factor for determining silver gelatin DOP paper sizes. Characterization by aspect ratio not only simplifies the dimensional diversity of silver gelatin paper by emphasizing their scaling relationships, but also highlights their relationship with other media. For example, 6:5 is common mainly with plate sizes, 5:4 is the aspect ratio of many large format films. 4:3 is the first motion picture aspect ratio and 8:5 is the golden ratio.
The measurements and other data were recorded in spreadsheets (the full results were published in JAIC, Volume 53, Issue 4 (November, 2014), pp. 219-235). It led to the conclusion that there is no easy answer to these questions. No system of standard paper sizes was successfully put in place for photographic papers. Additionally, available sizes varied widely over time and across geographic boundaries.
This research can be utilized in identification of artist’s methods and paper preferences. One useful application is to study photograms. This technique was used to great effect by Man Ray and Laszlo Maholy-Nagy, contemporaries working in France and Germany respectively. Of course, each print is unique, because it would be difficult to replicate the exact condition since no negative has been used. Of a selection of 163 prints by Man Ray dating from 1920 to 1940, there were 88 photograms and 75 traditional prints from negatives. Compared with the de facto standard sizes identified by this research, the dimensions of 39 Man Ray photograms (roughly 44%) correspond to de facto paper sizes. From 75 prints from negatives, only 25 (33%) correspond to the de facto paper sizes. This survey shows that Man Ray most likely trimmed his photographs from negatives, but didn’t trim his photograms. Averaging about 3.5 mm thickness, the photograms fall into the category of double weight papers.
Man Ray’s process contrasted with the working practices of Laszlo Maholy-Nagy. Print dimensions and estimated thickness for 216 prints by Maholy-Nagy made in Germany between 1922 and 1928 were collected from the catalogue raisonne of his photograms. Of these photograms, 216 or about 89% correspond to the de facto standard sizes identified by this research. The majority of the prints made from negatives were printed on two sizes of paper, 18 x 24 cm and 13 x 18 cm, both de facto standard sizes. This shows that Moholy-Nagy used full sheets of paper for his photograms and didn’t trim them down. The catalogue raisonne describes the thickness measurements of many Moholy-Nagy photograms as single weight or double weight. According to these descriptions Moholy-Nagy used the single weight or double weight papers in equal frequencies and sometimes used both in the same series.
Understanding the de facto standard sizes provides a useful point of comparison of these two artists. Differences in their methods can be due to a variety of factors. Moholy-Nagy was known for his scientific approach to photography, as a record of the interaction between light and physical object composed within the border of the paper. His photograms were complete upon processing. In contrast, Man Ray was more acutely engaged in producing highly refined settings of expression; attention to detail and subtle manipulation apply to all aspects of Man Ray’s photography as evidenced by his skilled practices in retouching and using carefully proportioned mounts.
In summary, there really were a lot photographic paper sizes available, particularly in middle of the 20th century, when these papers were extremely popular. While there are some de facto standard sizes and thicknesses, silver gelatin papers were made in numerous sizes and the majority of paper sizes listed in the references occurred only once.
PMG Winter Meeting – "New Photo Histories in West Africa" by Erin Haney, Feb. 21
This was the final session of the 2015 PMG Winter Meeting. Speaker Erin Haney is an art historian and co-founder/co-director of Resolution, which hosted the 2014 “3PA” workshop in Benin. During the Q&A afterward, one conservator remarked that her talk “reminds us why we do what we do.” That couldn’t be more true. She provided an exciting glimpse of family and private photograph collections in West Africa that have not been widely seen nor studied. The stewards of important West African photography collections have recently started to come together to explore strategies for their preservation as well as raising their visibility worldwide.
She began by saying that West Africa has valuable historic photographs that won’t come up on Google searches. The reason is simply that these photographs tend to be dispersed widely in private and family collections. There are very few cultural institutions, archives and museums that have enjoyed stability from the colonial era to the present day. Some institutions have lost all or part of their photographic collections in times of political upheaval. Instead, it is primarily families and private owners who have safeguarded that region’s photographic heritage.
Haney showed just a few examples that reflect the diversity of images that can be found in these collections. These include photographs made during the colonial period, the images made by the great, early studios (often now in family collections of their descendants), domestic portraits, group portraits, and events of social and political importance. There are images of the social elite and the wealthy, showing a materially rich and cosmopolitan West Africa that is seldom seen, and a history that is seldom taught. She showed a daguerreotype by Augustus Washington, who went to Liberia from the US and made daguerreotypes in cities all along the West African coast. There were photographs made by the Lutterodt family, which established a far-reaching network of family photography studios that operated from the 1870’s to the 1940’s. There were British colonial scenes, portraits by early French-run studios, portraits of West African women and their Bordeaux trader husbands, and debut portraits–young women dressed in the finest cloth, showing their readiness for marriage. More recent images included Gold Coast soldiers, independence movements, city skylines and infrastructure, and prominent political figures. These are but a few of the many treasures in these collections, spanning the 19th and 20th centuries. There is an extraordinary variety of subjects and photographic traditions.
She showed how photographs were made and remade in order to improve them and preserve them. Some photographs took on new meaning as memorial objects when the sitter passed away. These could be marked with crosses, mounted, and/or captioned by loved ones. Other photographs that had condition issues over time might be heavily overpainted to refresh them. In one case, a painting of a Dutch ancestor was remade by photographing it, in order to present it alongside a group of other family portrait photographs. The original image was not sacred. To study these collections, one has to understand how the images functioned when they were made and how they continue to function. Theirs is an iterative practice of artistry, which must inform preservation and conservation decision-making.
Of grave concern today is that these collections are at risk when the custodians feel they must sell or dispose of them to reclaim the valuable space they occupy in a private home, or generate much-needed income. Resolution communicates the importance of photographic cultural heritage to people in West Africa and around the world. The Benin workshop provided participants with the skills to document and manage their collections, while networking with others in the region working toward the same goals. The workshop involved nine countries in Francophone West Africa and is actively building partnerships and capacity to make a case for the ongoing support of photographic collections. There is a growing recognition of their critical importance for national identity, education and research. It was an inspiring end to this PMG Winter Meeting.