Can 3D Data Save Notre Dame Cathedral?

Dr. Lori Collins, Research Associate Professor and Director at the Digital Heritage and Humanities Center (DHHC), University of South Florida Libraries“Things that seem so robust, that have stood for hundreds or thousands of years, can turn out to be really fragile,” said Dr. Lori Collins, Research Associate Professor and Director at the Digital Heritage and Humanities Collections (DHHC), University of South Florida Libraries. Collins was referencing the catastrophic fire at Notre Dame that the world witnessed playing out on televisions and on social media.

As an experienced archeologist with decades of 3D scanning and digital capture of precious artifacts, including World Heritage buildings, monuments, and museum collections, Collins knows what she is talking about. She cites many references to lost heritage that could perhaps be rebuilt using 3D scan data. In September 2018, the National Museum in Rio de Janeiro, Brazil, burned down and took with it millions of historic artifacts. In 2017, ISIS ravaged historic sites throughout Syria. In 2001, the Taliban blew up the Buddhas of Banyan. The list goes on.

The Chalco monument which was 3D scanned prior to a disastrous fire.Closer to home for Collins and her team of researchers and specialists in the DHHC is a recent project they scanned in Mexico that also suffered from a devastating fire. In that case, the team prepared detailed CAD and 3D renders that they had previously collected using Geomagic software solutions that were used in the restoration of the ancient stone monument. “Our 3D data served as a guide for before and after documentation, and the models were used in the field by conservators during the treatment and restoration, providing accurate tools for conservation to our collaborators,” said Collins. “We were called the day of the disaster and asked if there was a way to use our data to help”. We immediately prepared “exploded views of the monument, showing how each part and piece fit together so that it could be easily viewed and understood.” Collins knew that their data could provide millimeter-level details that conservators could benefit from using their work.

“3D scanning of historic buildings, monuments, and artifacts, allows digital versions to exist and has potential to be reused in many ways,” said Collins, but she adds that often the digital version is not easy to use based on the sheer volume of data and formats in which it is saved, or is hard to access or discover. “As researchers we have in mind what we are collecting and using these data for, but the robust nature of laser scan information, and the ability to put these data into usable and accessible formats has much wider implications than just one research question.” Collins reflects on both her first-hand experiences and with the Notre Dame tragedy, that having access and discoverability associated with 3D heritage projects is vital in cases of disaster response and preservation monitoring and planning.

3D point cloud data of Notre Dame Cathedral“3D scanning, photogrammetry, and other media inputs work directly in the Geomagic software suites to deliver usable 3D data with textures and imaging, and can be saved in software neutral and archival formats” said Collins. “That allows architects, historians, and archeologists to be able to understand features, monitor and examine change to a building, and model and recreate elements in both digital and tangible ways.”

Spanning the years from 2005 to 2015 Dr. Andrew Tallon, a professor of Art History at Vassar College, 3D scanned the Notre Dame Cathedral in detail, collecting billions of measurable points. His models and work at the site are well known, having been highlighted in National Geographic and the subject of a number of articles and books. However in 2018, Dr. Tallon died of an aggressive form of cancer, and it is unclear whether the primary data sets collected will be able to be used to fulfill the promise of preservation that they hold. Additionally, factors of resolution, file formatting, and density of scan capture will all be critical factors in determining data usefulness and application.

Collins says this is a great example that speaks to the importance of not only site preservation, but data preservation. Her team in the USF Libraries is working to ensure that the hundreds of global projects that they have worked on are curated and discoverable into the future. As part of a new initiative that has brought together some of the major players in 3D heritage (CyArk, Historic Environments of Scotland, and USF DHHC), a new platform for sharing, learning and discovery of primary 3D heritage data is being formed. The Open Heritage Alliance will help guide these efforts and through their project collaboration are hoping to make sure that these data live on into the future.

“3D scanning and related technologies can provide tremendous value should an unanticipated event such as the fire at Notre Dame or other cultural heritage loss”, according to John Ristevski, chairman and CEO of CyArk, a non-profit organization that digitally records, archives and shares some of the world’s most significant cultural heritage sites. “We are continuing to work with partners to develop best approaches for organizing and making available content and data to the benefit of heritage preservation.”

Data accessibility using platforms that convert to useable products, and implementing archival and metadata standards while ensuring discoverability aspects of 3D projects may not be the sexiest part of 3D heritage work, but it may be the most visible aspect of heritage digital survey efforts. Collins says from her experience and in seeing the recent events in Paris strong efforts in these areas are needed. “We have to move beyond the hype of 3D, and libraries are proving to be an important partner in digital heritage efforts,” adding that “by partnering with 3D data capture leaders, industry partners, and the many voices that make up the heritage stakeholder universe, 3D can be an important tool for protecting and preserving places and information that matters.”