Geoffrey Schilling is Digital Production Technician at University of Arizona Libraries. He recently attended the IS&T Archiving Conference with support from the DPC Career Development Fund, which is funded by DPC Supporters.
Through a grant provided by the Digital Preservation Coalition’s Career Development Fund, I was fortunate enough to be given the opportunity to attend the IS&T Archiving 2025 conference in Granada, Spain. This year’s conference location was just down the hill from the breathtaking Alhambra and Generalife at the University of Granada’s Escuela Técnica Superior de Arquitectura.
While there was no shortage of fascinating presentations throughout the week, the ones on advanced imaging techniques were very pertinent to what our digital imaging team in Tucson, Arizona is working to achieve. Our kind hosts at the University of Granada’s Color Imaging Lab presented on hyperspectral imaging and their Hyperdoc project, John Barrett of Bodleian Libraries on the Selene photometric stereo system, and Frans Pegt of the Rijksmuseum on their photogrammetric reproduction of the Dutch painter Willem Witsen’s coat.
Ana Belén López Baldomero and Eva Valero Benito from UGR shared the work they’ve been doing in the Color Imaging Lab using hyperspectral imaging. This technique collects information from across the electromagnetic spectrum, allowing for the identification of materials by analyzing their unique spectral signatures, or “fingerprints.” By doing this, the team in the Color Imaging Lab is able to identify inks and pigments within manuscripts and historical documents, enabling researchers to have a more comprehensive understanding of the materials at hand. Their Hyperdoc project consists of a publicly accessible dataset that currently contains 1681 hyperspectral images, a software toolbox for automated analysis of spectral images, as well as a commitment to digitally preserving historical documents by integrating spectral imaging into their archives.
Designed by Jorge Cano of the Factum foundation, the Selene photometric stereo system is a non-contact and ultra high-resolution 3D and color recording system. This system uses four cameras positioned at different angles to record the surface texture of flat, or semi-flat, surfaces such as paintings, books, prints, copperplates, and much more. The Selene is able to record height variations equivalent to less than a fifth the width of a human hair, letting users view previously unseen details in incredibly high-definition and creates new possibilities for the digital preservation of collection items.
Willem Witsen was a Dutch impressionist painter and photographer whose studio is now a state-owned museum called the Witsenhuis. Since 1946, writers have been able to use the Witsenhuis as a temporary residence to hone their craft. Inside this studio, the artist’s painting coat is still on display. Frans Pegt of the Rijksmuseum used a photographic process known as photogrammetry to create a highly detailed, interactive 3D model of the coat. With the coat positioned on a turntable, the team was able to take hundreds of photos from different angles to capture every possible detail of the jacket, allowing for textures, weave, damage, and discrete details like moth holes or stitching to be shown. This method is an easy, accessible way for the public to study the object remotely, eliminating the need for the original object to be handled and possibly damaged.
These imaging techniques play a critical role in digital preservation by creating surrogates for at-risk items. They allow for non-invasive ways for people to interact with collection materials without causing any harm from handling the original artifacts. While items may continue to run the risk of deterioration, these digital surrogates will be able to maintain details that would otherwise be lost to time.
Acknowledgements
The Career Development Fund is sponsored by the DPC’s Supporters who recognize the benefit and seek to support a connected and trained digital preservation workforce. We gratefully acknowledge their financial support to this programme and ask applicants to acknowledge that support in any communications that result. At the time of writing, the Career Development Fund is supported by Arkivum, Artefactual Systems Inc., boxxe, Cerabyte, Evolved Binary, Ex Libris, HoloMem, Iron Mountain, Libnova, Max Communications, Preferred Media, Preservica and Simon P Wilson. A full list of supporters is online here.