Tag Archives: daguerreotypes

Seeing ghosts: recovering images from dageurreotypes with help from the Canadian Light Source (synchrotron)

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A daguerreotype plate with the photograph hidden by the tarnish (left) yet visible when imaged with synchrotron X-rays (right). Courtesy of Madalena Kozachuk.

Amazing, yes? Especially when you consider how devastating the inadvertent destruction of important daguerreotypes in an exhibition of US Civil War photography must have been to the curators and owners of the images. The ‘destruction’ occurred in 2005 and inspired research into the cause of the destruction, which was first covered here in a January 10, 2013 posting and followed up in a November 17, 2015 posting about an exhibit showcasing the results of the research.

A daguerreotype plate with the photograph hidden by the tarnish (left) yet visible when imaged with synchrotron X-rays (right). Courtesy of Madalena Kozachuk.

This latest research into daguerreotypes was performed at the Canadian Light Source (CLS; Saskatoon, Saskatchewan, Canada). Unlike my previous postings, this research was an attempt to retrieve the original image rather than research the reasons for its ‘destruction’. From a June 22, 2018 CLS news release (also on EurekAlert) by Lana Haight and Jeffrey Renaud (Note: Links have been removed),

Art curators will be able to recover images on daguerreotypes, the earliest form of photography that used silver plates, after scientists learned how to use light to see through degradation that has occurred over time.

Research published today [June 22, 2018] in Scientific Reports includes two images from the National Gallery of Canada’s photography research unit that show photographs that were taken, perhaps as early as 1850, but were no longer visible because of tarnish and other damage. The retrieved images, one of a woman and the other of a man, were beyond recognition.

“It’s somewhat haunting because they are anonymous and yet it is striking at the same time,” said Madalena Kozachuk, a PhD student in the Department of Chemistry at Western University [formerly University of Western Ontario] and lead author of the scientific paper.

“The image is totally unexpected because you don’t see it on the plate at all. It’s hidden behind time. But then we see it and we can see such fine details: the eyes, the folds of the clothing, the detailed embroidered patterns of the table cloth.”

The identities of the woman and the man are not known. It’s possible that the plates were produced in the United States, but they could be from Europe.

For the past three years, Kozachuk and an interdisciplinary team of scientists have been exploring how to use synchrotron technology to learn more about chemical changes that damage daguerreotypes.

Invented in 1839, daguerreotype images were created using a highly polished silver-coated copper plate that was sensitive to light when exposed to an iodine vapour. Subjects had to pose without moving for two to three minutes for the image to imprint on the plate, which was then developed as a photograph using a mercury vapour that was heated.

Kozachuk conducts much of her research at the Canadian Light Source and previously published results in scientific journals in 2017 and earlier this year. In those articles, the team members identified the chemical composition of the tarnish and how it changed from one point to another on a daguerreotype.

“We compared degradation that looked like corrosion versus a cloudiness from the residue from products used during the rinsing of the photographs versus degradation from the cover glass. When you look at these degraded photographs, you don’t see one type of degradation,” said Ian Coulthard, a senior scientist at the CLS and one of Kozachuk’s supervisors. He is also a co- author on the research papers.

This preliminary research at the CLS led to today’s [June 22, 2018] paper and the images Kozachuk collected at the Cornell High Energy Synchrotron Source where she was able to analyze the daguerreotypes in their entirety.

Kozachuk used rapid-scanning micro-X-ray fluorescence imaging to analyze the plates, which are about 7.5 cm wide, and identified where mercury was distributed on the plates. With an X-ray beam as small as 10 by 10 microns (a human scalp hair averages 75 microns across) and at an energy most sensitive to mercury absorption, the scan of each daguerreotype took about eight hours.

“Mercury is the major element that contributes to the imagery captured in these photographs. Even though the surface is tarnished, those image particles remain intact. By looking at the mercury, we can retrieve the image in great detail,” said Tsun-Kong (T.K.) Sham, Canada Research Chair in Materials and Synchrotron Radiation at Western University. He also is a co-author of the research and one of Kozachuk’s supervisors.

This is one of the many examples of successful research collaboration between Western University and CLS scientists.

Kozachuk’s research, which is ongoing, will contribute to improving how daguerreotype images are recovered when cleaning is possible and will provide a way to see what’s below the tarnish when cleaning is not possible. She will be back at the CLS this fall to continue her work.

The prospect of improved conservation methods intrigues John P. McElhone, recently retired as the chief of the Conservation and Technical Research branch at the Canadian Photography Institute of the National Gallery of Canada. He provided the daguerreotypes from the institute’s research collection.

“There are a lot of interesting questions that at this stage of our knowledge can only be answered by a sophisticated scientific approach,” said McElhone, another of the co-authors of today’s paper.

“A conservator’s first step is to have a full and complete understanding of what the material isand how it is assembled on a microscopic and even nanoscale level. We want to find out how the chemicals are arranged on the surface and that understanding gives us access to theories about how degradation happens and how that degradation can possibly or possibly not be reversed.”

As the first commercialized photographic process, the daguerreotype is thought to be the first “true” visual representation of history. Unlike painters who could use “poetic licence” in their work, the daguerreotype reflected precisely what was photographed.

Thousands and perhaps millions of daguerreotypes were created over 20 years in the 19th century before the process was replaced. The Canadian Photography Institute collection numbers more than 2,700, not including the daguerreotypes in the institute’s research collection.

By improving the process of restoring these centuries-old images, the scientists are contributing to the historical record. What was thought to be lost that showed the life and times of people from the 19th century can now be found. [emphases mine]

That last sentence seems to be borrowing from a line in the song, Amazing Grace, “I once was lost, but now am found,” from the song’s Wikipedia entry.

Here’s a link to and a citation for the paper,

Recovery of Degraded-Beyond-Recognition 19th Century Daguerreotypes with Rapid High Dynamic Range Elemental X-ray Fluorescence Imaging of Mercury L Emission by Madalena S. Kozachuk, Tsun-Kong Sham, Ronald R. Martin, Andrew J. Nelson, Ian Coulthard, & John P. McElhone. Scientific Reports volume 8, Article number: 9565 (2018) DOI:10.1038/s41598-018-27714 Published online June 22, 2018

This paper is open access. By the way, the research into the ‘destruction’ of the daguerreotypes in the 2005 exhibition? It’s cited in this paper.

When based on plastic materials, contemporary art can degrade quickly

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There’s an intriguing April 1, 2016 article by Josh Fischman for Scientific American about a problem with artworks from the 20th century and later—plastic-based materials (Note: A link has been removed),

Conservators at museums and art galleries have a big worry. They believe there is a good chance the art they showcase now will not be fit to be seen in one hundred years, according to researchers in a project  called Nanorestart. Why? After 1940, artists began using plastic-based material that was a far cry from the oil-based paints used by classical painters. Plastic is also far more fragile, it turns out. Its chemical bonds readily break. And they cannot be restored using techniques historically relied upon by conservators.

So art conservation scientists have turned to nanotechnology for help.

Sadly, there isn’t any detail in Fischman’s article (*ETA June 17, 2016 article [for Fast Company] by Charlie Sorrel, which features some good pictures, a succinct summary of Fischman’s article and a literary reference [Kurt Vonnegut’s Bluebeard]I*) about how nanotechnology is playing or might play a role in this conservation effort. Further investigation into the two projects (NanoRestART and POPART) mentioned by Fischman didn’t provide much more detail about NanoRestART’s science aspect but POPART does provide some details.

NanoRestART

It’s probably too soon (this project isn’t even a year-old) to be getting much in the way of the nanoscience details but NanoRestART has big plans according to its website homepage,

…

The conservation of this diverse cultural heritage requires advanced solutions at the cutting edge of modern chemistry and material science in an entirely new scientific framework that will be developed within NANORESTART project.

The NANORESTART project will focus on the synthesis of novel poly-functional nanomaterials and on the development of highly innovative restoration techniques to address the conservation of a wide variety of materials mainly used by modern and contemporary artists.

In NANORESTART, enterprises and academic centers of excellence in the field of synthesis and characterization of nano- and advanced materials have joined forces with complementary conservation institutions and freelance restorers. This multidisciplinary approach will cover the development of different materials in response to real conservation needs, the testing of such materials, the assessment of their environmental impact, and their industrial scalability.

NanoRestART’s (NANOmaterials for the REStoration of works of ART) project page spells out their goals in the order in which they are being approached,

…

The ground-breaking nature of our research can be more easily outlined by focussing on specific issues. The main conservation challenges that will be addressed in the project are:

 

Conservation challenge 1 – Cleaning of contemporary painted and plastic surfaces (CC1)

Conservation challenge 2 – Stabilization of canvases and painted layers in contemporary art (CC2)

Conservation challenge 3 – Removal of unwanted modern materials (CC3)

Conservation challenge 4 – Enhanced protection of artworks in museums and outdoors (CC4)

The European Commission provides more information about the project on its CORDIS website’s NanoRestART webpage including the start and end dates for the project and the consortium members,

From 2015-06-01 to 2018-12-01, ongoing project

CHALMERS TEKNISKA HOEGSKOLA AB
Sweden
MIRABILE ANTONIO
France
NATIONALMUSEET
Denmark
CONSIGLIO NAZIONALE DELLE RICERCHE
Italy
UNIVERSITY COLLEGE CORK, NATIONAL UNIVERSITY OF IRELAND, CORK
Ireland
MBN NANOMATERIALIA SPA
Italy
KEMIJSKI INSTITUT
Slovenia
CHEVALIER AURELIA
France
UNIVERSIDADE FEDERAL DO RIO GRANDE DO SUL
Brazil
UNIVERSITA CA’ FOSCARI VENEZIA
Italy
AKZO NOBEL PULP AND PERFORMANCE CHEMICALS AB
Sweden
COMMISSARIAT A L ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES
France
ARKEMA FRANCE SA
France
UNIVERSIDAD DE SANTIAGO DE COMPOSTELA
Spain
UNIVERSITY COLLEGE LONDON
United Kingdom
ZFB ZENTRUM FUR BUCHERHALTUNG GMBH
Germany
UNIVERSITAT DE BARCELONA
Spain
THE BOARD OF TRUSTEES OF THE TATE GALLERY
United Kingdom
ASSOCIAZIONE ITALIANA PER LA RICERCA INDUSTRIALE – AIRI
Italy
THE ART INSTITUTE OF CHICAGO
United States
MINISTERIO DE EDUCACION, CULTURA Y DEPORTE
Spain
STICHTING HET RIJKSMUSEUM
Netherlands
UNIVERSITEIT VAN AMSTERDAM
Netherlands
UNIVERSIDADE FEDERAL DO RIO DE JANEIRO
Brazil
ACCADEMIA DI BELLE ARTI DI BRERA
Italy

It was a bit surprising to see Brazil and the US as participants but The Art Institute of Chicago has done nanotechnology-enabled conservation in the past as per my March 24, 2014 posting about a Renoir painting. I’m not familiar with the Brazilian organization.

POPART

POPART (Preservation of Plastic Artefacts in museum collections) mentioned by Fischman was a European Commission project which ran from 2008 – 2012. Reports can be found on the CORDIS Popart webpage. The final report has some interesting bits (Note: I have added subheads in the [] square brackets),

To achieve a valid comparison of the various invasive and non-invasive techniques proposed for the identification and characterisation of plastics, a sample collection (SamCo) of plastics artefacts of about 100 standard and reference plastic objects was gathered. SamCo was made up of two kinds of reference materials: standards and objects. Each standard represents the reference material of a ‘pure’ plastic; while each object represents the reference of the same plastic as in the standards, but compounded with pigments, dyestuffs, fillers, anti oxidants, plasticizers etc.  Three partners ICN [Instituut Collectie Nederland], V&A [Victoria and Albert Museum] and Natmus [National Museet] collected different natural and synthetic plastics from the ICN reference collections of plastic objects, from flea markets, antique shops and from private collections and from their own collection to contribute to SamCo, the sample collection for identification by POPART partners. …

…

As a successive step, the collections of the following museums were surveyed:

-Victoria & Albert Museum (V&A), London, U.K.
-Stedelijk Museum, Amsterdam, The Netherlands
-Musée d’Art Moderne et d’Art Contemporaine (MAMAC) Nice, France
-Musée d’Art moderne, St. Etienne, France
-Musée Galliera, Paris, France

At the V&A approximately 200 objects were surveyed. Good or fair conservation conditions were found for about 85% of the objects, whereas the remaining 15% was in poor or even in unacceptable (3%) conditions. In particular, crazing and delamination of polyurethane faux leather and surface stickiness and darkening of plasticized PVC were observed. The situation at the Stedelijk Museum in Amsterdam was particularly favourable because a previous survey had been done in 1995 so that it was possible to make a comparison with the Popart survey in 2010. A total number of 40 objects, which comprised plastics early dating from the 1930’s until the newer plastics from the 1980’s, were considered and their actual conservation state compared with the 1995 records. Of the objects surveyed in 2010, it can be concluded that 21 remained in the same condition. 13 objects containing PA, PUR, PVC, PP or natural rubber changed due to chemical and physical degradation while works of art containing either PMMA or PS changed due to mechanical damages and incorrect artist’s technique (inappropriate adhesive) into a lesser condition. 6 works of art (containing either PA or PMMA or both) changed into a better condition due to restoration or replacements.  More than 230 objects have been examined in the 3 museums in France. A particular effort was devoted to the identification of the constituting plastics materials. Surveys have been undertaken without any sophisticated equipment, in order to work in museums everyday conditions. Plastics hidden by other materials or by paint layers were not or hardly accessible, it is why the final count of some plastics may be under estimated in the final results. Another outcome is that plastic identification has been made at a general level only, by trying to identify the polymer family each plastic belongs to. Lastly, evidence of chemical degradation processes that do not cause visible or perceptible damage have not been detected and could not be taken in account in the final results.

… The most damaged artefacts resulted constituted by cellulose acetate, cellulose nitrate and PVC.

[Polly (the doll)]

One of the main issues that is of interest for conservators and curators is to assess which kinds of plastics are most vulnerable to deterioration and to what extent they can deteriorate under the environmental conditions normally encountered in museums. Although one might expect that real time deterioration could be ascertained by a careful investigation of museum objects on display or in storage, real objects or artworks may not sampled due to ethical considerations. Therefore, reference objects were prepared by Natmus in the form of a doll (Polly) for simultaneous exposures in different environmental conditions. The doll comprised of 11 different plastics representative of types typically found in modern museum collections. The 16 identical dolls realized were exposed in different places, not only in normal exhibit conditions, but also in some selected extreme conditions to ascertain possible acceleration of the deterioration process. In most cases the environmental parameters were also measured. The dolls were periodically evaluated by visual inspection and in selected cases by instrumental analyses. 

…

In conclusion the experimental campaign carried out with Polly dolls can be viewed as a pilot study aimed at tackling the practical issues related to the monitoring of real three dimensional plastic artworks and the surrounding environment.

The overall exposure period (one year and half) was sufficient to observe initial changes in the more susceptible polymers, such as polyurethane ethers and esters, and polyamide, with detectable chromatic changes and surface effects. Conversely the other polymers were shown to be stable in the same conditions over this time period.

…

[Polly as an awareness raising tool]

Last but not least, the educational and communication benefits of an object like Polly facilitated the dissemination of the Popart Project to the public, and increased the awareness of issues associated with plastics in museum collections.

…

[Cleaning issues]

Mechanical cleaning has long been perceived as the least damaging technique to remove soiling from plastics. The results obtained from POPART suggest that the risks of introducing scratches or residues by mechanical cleaning are measurable. Some plastics were clearly more sensitive to mechanical damage than others. From the model plastics evaluated, HIPS was the most sensitive followed by HDPE, PVC, PMMA and CA. Scratches could not be measured on XPS due to its inhomogeneous surfaces. Plasticised PVC scratched easily, but appeared to repair itself because plasticiser migrated to surfaces and filled scratches.

Photo micrographs revealed that although all 22 cleaning materials evaluated in POPART scratched test plastics, some scratches were sufficiently shallow to be invisible to the naked eye. Duzzit and Scotch Brite sponges as well as all paper based products caused more scratching of surfaces than brushes and cloths. Some cleaning materials, notably Akapad yellow and white sponges, compressed air, latex and synthetic rubber sponges and goat hair brushes left residues on surfaces. These residues were only visible on glass-clear, transparent test plastics such as PMMA. HDPE and HIPS surfaces both had matte and roughened appearances after cleaning with dry-ice. XPS was completely destroyed by the treatment. No visible changes were present on PMMA and PVC.

Of the cleaning methods evaluated, only canned air, natural and synthetic feather duster left surfaces unchanged. Natural and synthetic feather duster, microfiber-, spectacle – and cotton cloths, cotton bud, sable hair brush and leather chamois showed good results when applied to clean model plastics.

Most mechanical cleaning materials induced static electricity after cleaning, causing immediate attraction of dust. It was also noticed that generally when adding an aqueous cleaning agent to a cleaning material, the area scratched was reduced. This implied that cleaning agents also functioned as lubricants. A similar effect was exhibited by white spirit and isopropanol.
Based on cleaning vectors, Judith Hofenk de Graaff detergent, distilled water and Dehypon LS45 were the least damaging cleaning agents for all model plastics evaluated. None of the aqueous cleaning agents caused visible changes when used in combination with the least damaging cleaning materials. Sable hair brush, synthetic feather duster and yellow Akapad sponge were unsuitable for applying aqueous cleaning agents. Polyvinyl acetate sponge swelled in contact with solvents and was only suitable for aqueous cleaning processes.

Based on cleaning vectors, white spirit was the least damaging solvent. Acetone and Surfynol 61 were the most damaging for all model plastics and cannot be recommended for cleaning plastics. Surfynol 61 dissolved polyvinyl acetate sponge and left a milky residue on surfaces, which was particularly apparent on clear PMMA surfaces. Surfynol 61 left residues on surfaces on evaporating and acetone evaporated too rapidly to lubricate cleaning materials thereby increasing scratching of surfaces.

Supercritical carbon dioxide induced discolouration and mechanical damage to the model plastics, particularly to XPS, CA and PMMA and should not be used for conservation cleaning of plastics.

…

Potential Impact:
Cultural heritage is recognised as an economical factor, the cost of decay of cultural heritage and the risk associated to some material in collection may be high. It is generally estimated that plastics, developed at great numbers since the 20th century’s interbellum, will not survive that long. This means that fewer generations will have access to lasting plastic art for study, contemplation and enjoyment. On the other hand will it normally be easier to reveal a contemporary object’s technological secrets because of better documentation and easier access to artists’ working methods, ideas and intentions. A first more or less world encompassing recognition of the problems involved with museum objects made wholly or in part of plastics was through the conference ‘Saving the twentieth century” held in Ottawa, Canada in 1991. This was followed later by ‘Modern Art, who cares’ in Amsterdam, The Netherlands in 1997, ‘Mortality Immortality? The Legacy of Modern Art’ in Los Angeles, USA in 1998 and, for example much more recent, ‘Plastics –Looking at the future and learning from the Past’ in London, UK in 2007. A growing professional interest in the care of plastics was clearly reflected in the creation of an ICOM-CC working group dedicated to modern materials in 1996, its name change to Modern Materials and Contemporary Art in 2002, and its growing membership from 60 at inception to over 200 at the 16th triennial conference in Lisbon, Portugal in 2011 and tentatively to over 300 as one of the aims put forward in the 2011-2014 programme of that ICOM-CC working group. …

[Intellectual property]

Another element pertaining to conservation of modern art is the copyright of artists that extends at least 50 years beyond their death. Both, damage, value and copyright may influence the way by which damage is measured through scientific analysis, more specifically through the application of invasive or non invasive techniques. Any selection of those will not only have an influence on the extent of observable damage, but also on the detail of information gathered and necessary to explain damage and to suggest conservation measures.

[How much is deteriorating?]

… it is obvious from surveys carried out in several museums in France, the UK and The Netherlands that from 15 to 35 % of what I would then call an average plastic material based collection is in a poor to unacceptable condition. However, some 75 % would require cleaning,

I hope to find out more about how nanotechnology is expected to be implemented in the conservation and preservation of plastic-based art. The NanoRestART project started in June 2015 and hopefully more information will be disseminated in the next year or so.

While it’s not directly related, there was some work with conservation of daguerreotypes (19th century photographic technique) and nanotechnology mentioned in my Nov. 17, 2015 posting which was a followup to my Jan. 10, 2015 posting about the project and the crisis precipitating it.

*ETA June 30, 2016: Here’s clip from a BBC programme, Science in Action broadcast on June 30, 2016 featuring a chat with some of the scientists involved in the NanoRestArt project (Note: This excerpt is from a longer programme and seemingly starts in the middle of a conversation,)

2015 daguerreotype exhibit follows problematic 2005 show

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In 2005, curators had a horrifying experience when historical images (daguerreotypes) were deteriorating as the 150-year old images were being displayed in an exhibit titled “Young America.” Some 25 of the photographs were affected, five of them sustaining critical damage. The debacle occasioned a research project involving conservators, physicists, and nanotechnology (see my Jan. 10, 2013 posting for more about the 2005 exhibit and resulting research project).

A new daguerreotype exhibit currently taking place showcases the results of that research according to a Nov. 13, 2015 University of Rochester news release,

In 1839, Louis-Jacques-Mandé Daguerre unveiled one of the world’s first successful photographic mediums: the daguerreotype. The process transformed the human experience by providing a means to capture light and record people, places, and events. The University of Rochester is leading groundbreaking nanotechnology research that explores the extraordinary qualities of this photographic process. A new exhibition in Rush Rhees Library showcases the results of this research, while bridging the gap between the sciences and the humanities. …

…

… From 2010-2014, a National Science Foundation grant supported nanotechnology research conducted by two University of Rochester scientists—Nicholas Bigelow, Lee A. DuBridge Professor of Physics, and Ralph Wiegandt, visiting research scientist and conservator—who explored how environment impacts the survival of these unique, non-reproducible images. In addition to conservation science and cultural research, Bigelow and Wiegandt are also investigating ways in which the chemical and physical processes used to create daguerreotypes can influence modern nanofabrication and nanotechnology.

“The daguerreotype should be considered one of humankind’s most disruptive technological advances,” Bigelow and Wiegandt said. “Not only was it the first successful imaging medium, it was also the first truly engineered nanotechnology. The daguerreotype was a prescient catalyst to the ensuing cascade of discoveries in physics and chemistry over the latter half of the 19th century and into the 20th.”

Blending the past with the future, the exhibition displays the first known daguerreotype of a Rochester graduating class (1853) alongside a 2015 daguerreotype of current University President Joel Seligman, created by Rochester daguerreotypist Irving Pobboravsky.

Both Bigelow and Wiegandt are mentioned in the 2013 posting describing the research project’s inception.

For anyone who’s in the area of New York state where the University of Rochester is located, the exhibit will run until February 29, 2016 in the Friedlander Lobby of Rush Rhees Library.  Plus, there’s this from the news release,

A special presentation about the scientific advances surrounding the daguerreotype and their relationship to cultural preservation will be led by Bigelow, Wiegandt, and Jim Kuhn, assistant dean for Special Collections and Preservation, on December 14 from 7-9 p.m. in the Hawkins-Carlson Room of Rush Rhees Library. For more information visit: http://www.library.rochester.edu/event/daguerreotype-exhibition or call (585).

There’s no indication that the special presentation will be livestreamed or recorded and made available at a later date.

Daguerreotypes*, history, and nanoengineering

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Can you imagine anything more horrifying for a curator at a museum to open a show with priceless examples of an art that is no longer practiced to find that the materials are deteriorating as you watch? Daniel Grushkin in his Dec. 12, 2012 article [full article is behind a paywall, link to preview] for Scientific American magazine sporting two titles: The Case of the Disappearing Daguerreotypes or Nano-Scientists Attempt to Save Disintegrating Artworks describes just what happened at the International Center of Photography’s (based in New York City) “Young America” exhibit of dageurreotypes in 2005 and the aftermath,

… These were the works of Albert Sands Southworth and Josiah Johnson Hawes, the Rembrandts of daguerreotypy — the first practical form of photography. A demure bride in white silk crepe fingered her ribbons; the stern and haughty statesman Daniel Webster glared from behind his brow. When the “Young America” exhibit opened in 2005, its 150-year-old images captured American icons at a time when the nation was transitioning from adolescence into a world power. “Each picture glows on the wall like a stone in a mood ring,” the New York Times raved in its review.

Yet after a month on exhibit, the silver plate-bound images began to degrade. … By the end of the two-and-a-half-month show, 25 daguerreotypes had been damaged, five of them critically.

Where daguerreotypes are concerned there is only an original as copying the image is not possible,

The vanishing images suggested that any daguerreotype could spontaneously crumble. Collectors feared they would lose their million-dollar collections. Conservators feared these windows into the 19th century might simply cloud over.

Taking action led to some unexpected places,

“I’ve been a conservator for nearly 30 years, and this object stands apart,” he [Ralph Wiegandt, a conservator at Eastman House who had designed the lighting and cases for the “Young America” exhibit] says. “Its entire meaning is in a molecular layer or two.” Because of the complex physics on the silver surface of daguerreotypes, the crisis called for an unlikely collaboration.

Wiegandt needed to partner with physicists. And in the course of their quest to understand the fading images, he and his partners would uncover surprising new molecular effects at the nanoscale. In doing so, the accidental relics of a 150-year-old technology may perhaps inspire the future of engineering.

Here’s what the researchers (Wiegandt and Nicholas Bigelow, physics and astronomy department chair at the University of Rochester) discovered,

Louis-Jacques-Mandé Daguerre, a Parisian artist and showman, introduced the medium in 1839, after a decade of searching for a way to fix an image on a silver plate. One day, the story goes, he accidentally broke a thermometer and absently put it in a cabinet with his silver plates. The following day he found that the mercury vapor had somehow made the image permanent. Daguerre had discovered the chemistry of image making. “What was really going on was self-assembling nano-structures,” Bigelow says. “Whether or not he meant to, he was doing nanoengineering.”

As noted in Grushkin’s article there are many reasons why daguerreotypes are fragile from above and, surprisingly, below,

… In collaboration with researchers at Kodak, Wiegandt’s team punched a 30-micron-long rectangle through the surface of sample daguerreotypes using a focused ion beam. They then examined the layers in cross section. To their surprise, they saw 300-nanometer-wide voids just under the surface — a network of tunnels running just beneath the image.

…

The voids could explain why some of the daguerreotypes in the exhibit showed damage. Over the course of 150 years chlorine or other contaminants might have seeped into these voids. When the pictures went on display, light may have triggered subsurface reactions between the chlorine and silver, causing the images to sprout spots from below.

Unfortunately, the damage cannot be repaired but Wiegandt and his colleagues will be able to use the information to help preserve remaining daguerreotypes. Grushkin’s article does not speculate about how these discoveries might be applied to nanoscale engineering but I imagine that would entail another article.

*’Dageurreotypes’ corrected to ‘Daguerreotypes’ on Nov. 16, 2015.