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Tales from the Archives

Tales from the Archives: Around the Table: Research Technologies

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In 2019, I spoke with Helen Davies and Alexander Zawacki, Program Coordinators of the Lazarus Project. Since that time, the project has continued to thrive and multispectral imaging has become an increasingly popular methodology for examining manuscripts and a particularly useful one when dealing with the stains, erasures, and other common marks found in recipe texts. The Rare Book School now offers a course on multispectral imaging and other scientific methods of book analysis, and the Coding Codices podcast recently highlighted the Lazarus Project in a conversation with Helen, now an assistant professor of English at the University of Colorado, Colorado Springs, Alex, still serving as a Program Coordinator, and Katie Albers-Morris, also a current Program Coordinator. Today we revisit this Around the Table chat for a helpful explanation of imaging and the Lazarus project. -Sarah Kernan

This month on Around the Table, I am speaking with Helen Davies and Alexander Zawacki, Program Coordinators of the Lazarus Project and PhD students in English at the University of Rochester. This month on the Recipes Project, we’ve explored all kinds of ideas about texture. Now, we’ll get a chance to learn about digital textures, and how technologies like multispectral imaging can help scholars unearth new information about manuscripts. Those of us dealing with manuscript recipes from any time period are accustomed to erasures, stains, and layers of writing. Helen and Alex provide information about the ways in which multispectral imaging can help us interpret these elements of our sources.

Tell us a bit about the Lazarus Project. Do you work with materials from a specific time or place? With what sorts of projects and partnerships has your lab been involved?

The Lazarus Project is a multispectral imaging endeavor located at the University of Rochester. We’re a mix of professors, graduate students, and undergraduates from a range of different fields all working to use cutting-edge technology to digitally recover lost texts and images. Many of us — Helen, Alex, PhD Candidate Kyle Huskin, and our advisor (and the director of the project) Gregory Heyworth — are medievalists, and so many of projects tend to focus on objects from that time period in Western Europe, but we’ve also worked on Biblical manuscripts from Egypt, pre-Columbian material from the Americas, postcards sent from concentration camps and censored by the Nazis, and eighteenth-century musical scores from Germany. We’ve partnered in the past with (to name just a few) the United States Holocaust Museum, the Folger Library, the Beinecke Library, the Saxon State and University Library Dresden, the Vercelli Chapter Library in Italy, and the Bodleian Library.

How does your lab select items to analyze? Do libraries and organizations reach out to you, or do you seek out specific items and projects?

A bit of both. Sometimes we’ll find objects that we particularly want to work on, and set about applying for grants and searching for funding to make that happen. Other times institutions or even private individuals will reach out to us about an object in their care that they would like to have imaged.

Could you explain how multispectral imaging works? Can you provide a few examples of what scholars can learn about books with this technology?

We take an object — a manuscript, for example — and photograph it first under discrete wavelengths of light, moving from the ultraviolet through to the infrared. Then we take another series of images under only ultraviolet, violet, and blue light, which induces fluorescence in the object, like when you wear a white t-shirt under a blacklight. We use filters to separate out different wavelengths from the fluorescence that the object emits, trying to squeeze as much data out of it as possible. Lastly, we take a final group of photographs while shining light upwards through the manuscript, which has the potential to reveal “ghost letters” — places where the ink has been removed, but the parchment has thinned enough to reveal where it used to be.

Photographing the object is only the very tip of the iceberg, though — almost never do any of the images reveal all or even much of what we’re looking for. Next, we process the images using software originally designed to analyze satellite and aerial imagery. This can be a very laborious and time-consuming process.

Our goal is to recover texts and images that have been lost to time and damage. Palimpsests are a great example of the kind of thing that scholars can learn using this technology. In the medieval period, people would sometimes erase entire manuscripts by scraping or washing the parchment clean, and then re-use the pages to make a new book. The “undertext” — the book that was erased — is often illegible, far too faint and obscured by overwriting to read. We try to make that undertext visible again, usually for the first time in centuries. Other times we work on objects that have been damaged by fire, water, chemical staining, or simple fading, all with the goal of bringing scholars new texts to work on and study.

During a July 2019 workshop on Spectral Imaging in Cultural Heritage, the Lazarus Project team shared information about imaging methods with a group of participants. Participants at the workshop could see how chemical reagents are used on palimpsested manuscripts. Pictured here: pumice is used to palimpsest parchment, and then a reagent reveals the erased writing.

As you know, our readers deal with recipes of all kinds (medical, household, culinary, alchemical, etc.) We encounter strange marks and stains all the time in our books! What can multispectral imaging tell us about those marks and stains?

Multispectral imaging can help readers work with a variety of stains and marks in a variety of ways. Firstly, we can help you see through them. MSI can help readers see underneath the stains. This can be very important in manuscripts whatever been treated in chemical reagents. As you and your readers likely know, chemical reagents were widely used for a time in order to bring out ink that had faded. Yet this momentary gain in legibility was frequently followed by long term damage to the manuscript. MSI can help digitally reverse these stains. Hyperspectral and other imaging modalities can be leveraged to look at material composition of stains. Multispectral, however, mostly helps with legibility rather than material analysis. A group of scholars has recently tried to push the material analysis capabilities in new directions through the Library of Stains project.

At the workshop, an image of the Rotovap system distilling the wine + oak gall solution.

What kind of training or partnerships might be necessary for a humanities scholar without a digital background to incorporate imaging into their research?

An interested humanities scholar would first need to either purchase a multispectral imaging system or partner with a group or institution that owns one. This partnership could take the form of receiving some training in operating the technology (unless the group would be doing both the imaging and the processing, as we often do) or being lead scholar on the project.  Training could incorporate learning more about MSI on site or image processing training. There is a range of software available for processing including ENVI (which we use), Matlab, Python or Image J (for which imaging professionals built various custom toolkits). A lead scholar partnership involves a humanities scholar reaching out to us for imaging, working with us to secure funding for the project, and then this individual driving the research. We will work with them to ensure we get as much data as possible from an item, but they lead the transcription, translation and examination of the document. This gives non-digitally inclined scholars the opportunity to work with multispectral images and recovered texts.

How did you become interested and involved in digital humanities and the Lazarus Project?

All of our team members have come to the Lazarus Project through different routes.

Helen: I had the opportunity to photograph early print books in the York Minster Library while working on my MA in Medieval Studies. This led to me pursuing a digital humanities MA and further imaging jobs. Eventually, a friend of a friend asked me to do some work for Lazarus and then Greg encouraged me to apply for a PhD to continue learning from and working with the project.

Also at the workshop, Alex Zawacki transfers the reagent.

Alex: I found out about the project as a first year PhD student at the University of Rochester. I was fascinated by the idea of recovering lost texts. I started working with the project to see what we could find, and I am now cultivating my own projects to search for lost material in my own field.

Do you have any favorite Lazarus Project items you’ve worked with, so far?

We all have our own individual favorites we have worked on in the past.

Helen: My all-time favorite is the damaged medieval world map in Vercelli, Italy. There are only a handful of large scale medieval wall maps to survive (others have fallen victim to bombs, binders and other forms of destruction). The map in Vercelli survives, but has been largely unreadable. We have imaged it, recovered it, and, I am happy to report, as of last week I have created an entirely new digital facsimile of the document. However, I have loved getting the chance to work on a variety of objects from ancient coins to Old English poems to early modern globes.

Alex: I’m torn between the Codex Boenerianus, the Black Book of Camarthen, and a single manuscript fragment from the University of Rochester’s Rare Books and Special Collections department. The latter had been used as a binding fragment and was terribly faded and stained. No one had been able to read any of it in the 50 years that it had been in the university’s care. That one was particularly rewarding, as not only were we able to recover nearly the whole text, identify the work to which it belonged (Richard FitzRalph’s Summa Questionibus Armenorum), and trace some of its provenance and history as an object, we also found that it was the only witness to that text in a non-European library — and very possibly the oldest extant witness.

Thanks, Helen and Alex, for chatting with me about multispectral imaging! You can follow the Lazarus Project on Twitter @Lazarus_Imaging, Facebook @LazarusProjectImaging, and Instagram @lazarusprojectimaging. If you’d like to feature a project, scholar, or institution on Around the Table, please email Sarah Kernan.

Around the Table

Around the Table: Research Technologies

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This month on Around the Table, I am speaking with Helen Davies and Alexander Zawacki, Program Coordinators of the Lazarus Project and PhD students in English at the University of Rochester. This month on the Recipes Project, we’ve explored all kinds of ideas about texture. Now, we’ll get a chance to learn about digital textures, and how technologies like multispectral imaging can help scholars unearth new information about manuscripts. Those of us dealing with manuscript recipes from any time period are accustomed to erasures, stains, and layers of writing. Helen and Alex provide information about the ways in which multispectral imaging can help us interpret these elements of our sources.

Tell us a bit about the Lazarus Project. Do you work with materials from a specific time or place? With what sorts of projects and partnerships has your lab been involved?

The Lazarus Project is a multispectral imaging endeavor located at the University of Rochester. We’re a mix of professors, graduate students, and undergraduates from a range of different fields all working to use cutting-edge technology to digitally recover lost texts and images. Many of us — Helen, Alex, PhD Candidate Kyle Huskin, and our advisor (and the director of the project) Gregory Heyworth — are medievalists, and so many of projects tend to focus on objects from that time period in Western Europe, but we’ve also worked on Biblical manuscripts from Egypt, pre-Columbian material from the Americas, postcards sent from concentration camps and censored by the Nazis, and eighteenth-century musical scores from Germany. We’ve partnered in the past with (to name just a few) the United States Holocaust Museum, the Folger Library, the Beinecke Library, the Saxon State and University Library Dresden, the Vercelli Chapter Library in Italy, and the Bodleian Library.

How does your lab select items to analyze? Do libraries and organizations reach out to you, or do you seek out specific items and projects?

A bit of both. Sometimes we’ll find objects that we particularly want to work on, and set about applying for grants and searching for funding to make that happen. Other times institutions or even private individuals will reach out to us about an object in their care that they would like to have imaged.

Could you explain how multispectral imaging works? Can you provide a few examples of what scholars can learn about books with this technology?

We take an object — a manuscript, for example — and photograph it first under discrete wavelengths of light, moving from the ultraviolet through to the infrared. Then we take another series of images under only ultraviolet, violet, and blue light, which induces fluorescence in the object, like when you wear a white t-shirt under a blacklight. We use filters to separate out different wavelengths from the fluorescence that the object emits, trying to squeeze as much data out of it as possible. Lastly, we take a final group of photographs while shining light upwards through the manuscript, which has the potential to reveal “ghost letters” — places where the ink has been removed, but the parchment has thinned enough to reveal where it used to be.

Photographing the object is only the very tip of the iceberg, though — almost never do any of the images reveal all or even much of what we’re looking for. Next, we process the images using software originally designed to analyze satellite and aerial imagery. This can be a very laborious and time-consuming process.

Our goal is to recover texts and images that have been lost to time and damage. Palimpsests are a great example of the kind of thing that scholars can learn using this technology. In the medieval period, people would sometimes erase entire manuscripts by scraping or washing the parchment clean, and then re-use the pages to make a new book. The “undertext” — the book that was erased — is often illegible, far too faint and obscured by overwriting to read. We try to make that undertext visible again, usually for the first time in centuries. Other times we work on objects that have been damaged by fire, water, chemical staining, or simple fading, all with the goal of bringing scholars new texts to work on and study.

During a July 2019 workshop on Spectral Imaging in Cultural Heritage, the Lazarus Project team shared information about imaging methods with a group of participants. Participants at the workshop could see how chemical reagents are used on palimpsested manuscripts. Pictured here: pumice is used to palimpsest parchment, and then a reagent reveals the erased writing.

As you know, our readers deal with recipes of all kinds (medical, household, culinary, alchemical, etc.) We encounter strange marks and stains all the time in our books! What can multispectral imaging tell us about those marks and stains?

Multispectral imaging can help readers work with a variety of stains and marks in a variety of ways. Firstly, we can help you see through them. MSI can help readers see underneath the stains. This can be very important in manuscripts whatever been treated in chemical reagents. As you and your readers likely know, chemical reagents were widely used for a time in order to bring out ink that had faded. Yet this momentary gain in legibility was frequently followed by long term damage to the manuscript. MSI can help digitally reverse these stains. Hyperspectral and other imaging modalities can be leveraged to look at material composition of stains. Multispectral, however, mostly helps with legibility rather than material analysis. A group of scholars has recently tried to push the material analysis capabilities in new directions through the Library of Stains project.

At the workshop, an image of the Rotovap system distilling the wine + oak gall solution.

What kind of training or partnerships might be necessary for a humanities scholar without a digital background to incorporate imaging into their research?

An interested humanities scholar would first need to either purchase a multispectral imaging system or partner with a group or institution that owns one. This partnership could take the form of receiving some training in operating the technology (unless the group would be doing both the imaging and the processing, as we often do) or being lead scholar on the project.  Training could incorporate learning more about MSI on site or image processing training. There is a range of software available for processing including ENVI (which we use), Matlab, Python or Image J (for which imaging professionals built various custom toolkits). A lead scholar partnership involves a humanities scholar reaching out to us for imaging, working with us to secure funding for the project, and then this individual driving the research. We will work with them to ensure we get as much data as possible from an item, but they lead the transcription, translation and examination of the document. This gives non-digitally inclined scholars the opportunity to work with multispectral images and recovered texts.

How did you become interested and involved in digital humanities and the Lazarus Project?

All of our team members have come to the Lazarus Project through different routes.

Helen: I had the opportunity to photograph early print books in the York Minster Library while working on my MA in Medieval Studies. This led to me pursuing a digital humanities MA and further imaging jobs. Eventually, a friend of a friend asked me to do some work for Lazarus and then Greg encouraged me to apply for a PhD to continue learning from and working with the project.

Also at the workshop, Alex Zawacki transfers the reagent.

Alex: I found out about the project as a first year PhD student at the University of Rochester. I was fascinated by the idea of recovering lost texts. I started working with the project to see what we could find, and I am now cultivating my own projects to search for lost material in my own field.

Do you have any favorite Lazarus Project items you’ve worked with, so far?

We all have our own individual favorites we have worked on in the past.

Helen: My all-time favorite is the damaged medieval world map in Vercelli, Italy. There are only a handful of large scale medieval wall maps to survive (others have fallen victim to bombs, binders and other forms of destruction). The map in Vercelli survives, but has been largely unreadable. We have imaged it, recovered it, and, I am happy to report, as of last week I have created an entirely new digital facsimile of the document. However, I have loved getting the chance to work on a variety of objects from ancient coins to Old English poems to early modern globes.

Alex: I’m torn between the Codex Boenerianus, the Black Book of Camarthen, and a single manuscript fragment from the University of Rochester’s Rare Books and Special Collections department. The latter had been used as a binding fragment and was terribly faded and stained. No one had been able to read any of it in the 50 years that it had been in the university’s care. That one was particularly rewarding, as not only were we able to recover nearly the whole text, identify the work to which it belonged (Richard FitzRalph’s Summa Questionibus Armenorum), and trace some of its provenance and history as an object, we also found that it was the only witness to that text in a non-European library — and very possibly the oldest extant witness.

Thanks, Helen and Alex, for chatting with me about multispectral imaging! You can follow the Lazarus Project on Twitter @Lazarus_Imaging, Facebook @LazarusProjectImaging, and Instagram @lazarusprojectimaging. If you’d like to feature a project, scholar, or institution on Around the Table, please email Sarah Kernan.