In the Lab: Conversation with Chemist Madalena Kozachuk

Unknown, Portrait of a Woman and Man, c.1850

Unknown, Portrait of a Woman and Man, c.1850, daguerreotype, 7.6 x 6.3 cm, Study Collection, National Gallery of Canada, Ottawa. Photo: NGC


Since its invention in 1839, photography has been intertwined with science in ways far beyond the production of images. Photographic processes and materials offer an ever-evolving field of experimentation and new discoveries reveal a little more each day about the mysteries that shape reality. As Aristotle once suggested, it is through experimentation that science and art advance.

In 2017, Madalena Kozachuk — then a doctoral candidate in chemistry from Western University  in London, Ontario — was selected for the Canadian Photography Institute (CPI) fellowship program at the National Gallery of Canada. As part of a collaborative research project, she has been using chemistry to examine 19th-century photographs in the collection.

Conservation experts from the Gallery introduced her to tarnished daguerreotypes from the study collection. Kozachuk and her team used synchrotron radiation to map the images’ surface composition, which revealed visual features that had long since vanished. The discovery opens up a wide range of possibilities for conservators when it comes to developing preservation methods for daguerreotypes, which are an important part of the national collection.

Madalena Kozachuk was guided in this work by her supervisors Dr. Tsun-Kong Sham, Dr. Ronald Martin, and Dr. Andrew Nelson at Western University, and Dr. Ian Coulthard at the Canadian Light Source in Saskatoon, as well as experts from the Canadian Photography Institute.

Curious about this fascinating story, we met with her to chat about her fellowship experience.

Madalena Kozachuk. Photo: Markian Lozowchuk

Madalena Kozachuk. Photo: Markian Lozowchuk



CPI Staff: How does the conservation lab here compare to the lab in which you normally work. Is it similar? Different?

Madalena Kozachuk: The lab I have been working in at Western University is different in the sense that there are more instruments and chemicals. It looks industrial, compared to the art-centric equipment and facilities in the conservation lab at the National Gallery of Canada.

My day-to-day work at Western University mostly involved analyzing data gathered from my trips to different synchrotron sources, whether in Saskatoon — where the only Canadian synchrotron is located — or at Cornell High Energy Synchrotron Source in Ithaca, New York. In these places, you notice the technology right away; there are all sorts of screens, monitors and wires everywhere.


CPI: Why did you want to come to the NGC/CPI conservation lab?

MK: The goal of my fellowship was to do daguerreotypes cleaning alongside John McElhone, who is an expert in photographic conservation. One instrument that was introduced to me at the NGC/CPI conservation lab was an electric cleaner that, through variable current, can remove tarnish from a daguerreotype’s full-plate. The technique involved was not necessarily new to me, but the scale of the cleaning was, because the work I had done before was only on small localized spots.

The major thing for me was to work alongside art conservators, because of their frequent interactions with art objects. Their opinions and thoughts on interacting, treating, storing, handling and shipping these objects was something I wanted to learn more about.


CPI: Did you ever think your work would be applied to an artistic discipline?

MK: That was my goal from the get-go! I would have loved to go to art school, but was strongly encouraged to pursue science. Being able to loop back to art made chemistry studies more interesting to me. I did a Bachelor’s degree in Science, with a double major in chemistry and art history. In my final year, my research project was on boxwood miniatures exhibited at the Art Gallery of Ontario. These are tiny carved wooden boxes that open up. The research team was doing MicroCT scanning of them to get 3D images. They wondered if the exposure of wood to X-rays was having a negative impact on the objects, so this became my undergraduate thesis topic and led to my first published article

For my graduate research project, I wanted to continue studying the application of chemistry to cultural heritage. I did not know right away that it would be about daguerreotypes, but I am pleased that John McElhone introduced me to these amazing art objects.

Unknown, Portrait of a Man, c. 1839-1855

Image 1 (left): Unknown, Portrait of a Man, c. 1839-1855, daguerreotype, 7.3 x 6.5 cm, Study Collection, National Gallery of Canada, Ottawa. Photo: NGC

Image 2 (right): Micro-X-ray fluorescence map of the mercury signal on daguerreotype (Image A) acquired from the Cornell High Energy Synchrotron Source. Maximum relative counts of mercury are represented by white on the grey scale; the minimum amount of relative counts of mercury is represented by black on the grey scale. Photo: Nature Scientific Reports


CPI: What is special to you about daguerreotypes?

MK: I found them very interesting from a history-of-technology point of view. They were the first commercially viable way of preserving a realistic image. The fact that a daguerreotype exists in only one copy is fascinating.

I also find them mesmerizing, because of the depth afforded by the silver coated copper plate. The resolution of the image is amazing; they really do have a sense of mystery. They are often called "mirrors with a memory," because you not only see the image, but also a reflection of yourself in its surface.

I would also say that the complexity of these art objects makes them special. It requires a variety of disciplines to fully understand their interdisciplinary nature, including metallurgy, corrosion, electrical chemistry, art history — and even anthropology when it comes to the people and landscapes in the images. They are breathtaking to look at, but also intellectually stimulating!


CPI: Could you tell us a bit about what you discovered while studying these objects?

MK: The image in a daguerreotype results from the specific distribution and density of small silver-mercury particles across the surface. The way these particles are arranged changes how light is reflected. One of the things we found is that we can track the distribution of mercury (and hence the particles that make up the image) using synchrotron radiation X-ray fluorescence imaging.

We started by doing small-scale scans of a square centimetre at the Canadian Light Source in Saskatoon. At the Cornell High Energy Synchrotron Source, we were able to scale up to a full size scan of the plate. We discovered that, by tracking the mercury signature on the surface, we could re-image the plate, producing a digital chemical map of the original image hidden beneath the tarnish.

This has major implications for the conservation community, as well as private and public collecting institutions. It means we can possibly retrieve chemical information on daguerreotypes that have been damaged by time. It opens up a whole new set of possibilities in terms of documenting plates and producing a digital copy. For example, the digital copy could be exhibited alongside the original, or even serve to produce a new daguerreotype.


CPI: Do you have any advice for students like you who have an interest in both science and art?

MK: Number one would be: talk to people. So much of the cooperative process happens by communicating and figuring out what sorts of questions matter to different researchers. It is also important to find people who are open to collaboration, and willing to pursue it.

Part of the challenge, when you are working in association with others, is getting things done. Everyone is already so busy with their day-to-day work, but if you can find people who have successfully collaborated in the past, there may be an established team already capable of undertaking collaborative research. So, I would say, don’t be afraid to reach out. People really are willing to share their expertise if they feel you are genuinely interested.

Back when the daguerreotype was invented, art and science were intensely intertwined. Now, however, we have gained so much knowledge that everyone has become narrowly focused. A lot of the time, we lose sight of the big picture, so I think collaborative work is more and more important. A wide range of skills and knowledge from multiple disciplines should be part of every research project.

Unknown, Portrait of a woman, c.1850

Image 1 (left): Unknown, Portrait of a woman, c.1850, daguerreotype, 7.3 x 6.5 cm, RCL Study Collection, National Gallery of Canada, Ottawa. Photo: NGC

Image 2 (right): Micro-X-ray fluorescence map of the mercury signal on daguerreotype (Image 1) acquired from the Cornell High Energy Synchrotron Source. Maximum relative counts of mercury are represented by white on the grey scale; the minimum amount of relative counts of mercury is represented by black on the grey scale. Photo: Nature Scientific Reports


Watch a video interview produced by the press about this research project.  


Find more information about the Research Fellowship Program at the Canadian Photography Institute.



About the Author

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Scotiabank Photography Program


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Programme de photographie Banque Scotia