Few people outside certain techie and cultural heritage circles had ever heard about self-described ‘gadget geek’ Andrew Tallon’s work until Monday, when Notre Dame cathedral in Paris went up in a cloud of smoke.
Tallon, a Belgium-born Vassar College art professor who died six months ago at the age of 49, of terminal brain cancer, was the first—and the last—person to digitally scan the entire 850-year-old cathedral. He used special lasers to create one billion data points, which he did as a labor of love, driven by obsession.
His precise measurements, which are accurate to within five millimeters or 0.1969 inches, are now the only modern record of the cathedral just as it was on the day it was partially destroyed, which will prove invaluable to those who hope to rebuild it—if French authorities ask for them.
Tallon’s work wasn’t taken very seriously when he first started scanning structures. He majored in medieval music in Wisconsin and, for a time, contemplated becoming a monk. He ended up a tenured professor in Vassar’s art department. He learned digital scanning techniques on the side and eventually scanned 45 ancient buildings as a hobby. The holy grail was getting the access he needed to Notre Dame, which he finally got in 2015 shortly before he was diagnosed with terminal brain cancer.
Roberto Viola, the European Commission’s director-general for communications networks, content and technology, did take Tallon and his work seriously. And, in what is part creepy premonition and part forward thinking, on April 9—one week before the tragic fire—he used Tallon’s digitization of Notre Dame as an example of a “what if the worst would happen” scenario to try to convince 24 European countries to sign on to a declaration of cooperation on advancing digitization of cultural heritage. Viola says his group wants every major cultural heritage site in Europe digitized, both so they can be repaired if they are destroyed by natural or human disaster, and also so that fissures and other structural weaknesses can be found.
“I knew I was right, but I had no idea just how right,” he told The Daily Beast about the need for digitization of ancient structures. “I wish Dr. Tallon could have seen how important his work would be.”
Tallon became obsessed with Notre Dame when he was in the fourth grade. That year he lived in Paris with his mother while she worked on her theater history dissertation, and he spent all his free time inside the cathedral. “I had this little guidebook and I annotated it like a nutcase,” he told National Geographic in 2015. “I longed to know the usual questions. Who made that thing? How did they make it? Could I ever go up in one of those passages?”
But he couldn't tell his art colleagues what he was doing, so he kept his obsession with the Gothic cathedral and his dream to digitize it a secret. “I have a career I don’t really tell my French colleagues about because they’ll think I’m not serious,” he said.
Work to digitally scan structures is both expensive and time-consuming. Tallon created a billion data points with his laser scanners inside Notre Dame by taking panoramic laser scans from 50 different spots, including from the high rafters that are sadly no longer there. He also took panoramic photographs at each scanning point, which he then used as a background for the scans to help create an exact replica of the building. All the data can be melded together to create a full 3-D model that will be exactly to scale.
French authorities have not yet asked for Tallon’s data, but Vassar said on Thursday that it would be happy to cooperate if they do. “If eventually the authorities wish to use this, then of course it would be shared with them,” Tallon’s former student on the project Lindsay Cook told the AFP.
Still, it will take decades to digitally scan every vulnerable historical building just in case something happens to it. Tallon eventually won grants to fund his passion, and Vassar cooperated by providing the digital storage. Copies of some of the scans are also at Columbia University, where they were used on a joint project called “Mapping Gothic” that Tallon was working on when he died last November.
Currently, only 10 percent of the world’s historic sites are digitized, Tibor Navracsics, the E.U.'s commissioner for education and culture, said at the April 9 meeting. “We need to find ways to make our cultural heritage accessible to all. Digital means have an important role to play in this,” he said. “Everyone should have the opportunity to discover how they belong to the complex tapestry that is Europe, no matter their socio-economic background.”
In many ways, Tallon could save Notre Dame twice. When he finished his scans of Notre Dame four years ago, he noticed vulnerable areas that looked like they would soon crumble and sounded the alarm bell to a number of groups that privately raised funds for restoration. While the French government was ultimately stingy with funding, Tallon warned that if repairs weren’t made, the whole building could collapse. “The damage can only accelerate,” he told Time magazine in 2017. “The more you wait, the more you need to take down and replace.”
On the morning after the fire, Viola tweeted his worst fears. “I fell asleep hoping to wake up from a bad dream,” he wrote. “Europe is full of wonders that no one will bring us back. Preserving with #digitization is important for us & for future generations. Close to the Parisians. With #NotreDame we've lost a piece of our history.”
Now, thanks to Tallon’s obsession, they know exactly what the lost treasure looked like.