It’s a technology that can create complex architectural records of century-old buildings without the instruments typically used by historians and architects, such as measuring tapes, dusty archives and rolls of blueprints. And it’s conducted so quickly and accurately that it almost feels like historic preservation by hocus-pocus.
This summer, “digital presentation” teams descended on New Orleans to begin creating a digital record of the city’s historic neighborhoods using cameras that send and receive 700,000 points of light per second. By recording what bounces back, the cameras form images, much the same way dolphins and bats use sound waves to determine what’s in front of them.
New Orleans was at the top of the list of cities targeted for this type of digital preservation because of its risk of losing historic properties to hurricanes and floods, said Elizabeth Lee, vice president of California-based nonprofit CyArk, which is short for Cyber Archive.
On Tuesday, the group will present its scans of New Orleans and Philadelphia at the National Archives in Washington, D.C.
CyArk has already used this method to create digital records of other national treasures. To examine cracks in the carved faces of Mount Rushmore, the agency’s teams spent two weeks pointing their camera-mounted lasers at every angle of the colossal monument, even climbing inside the presidents’ noses and eyes to capture every detail.
This summer, to begin the work in New Orleans, cars mounted with cameras shooting laser light pulses scanned 277 miles of city streets in three days. A division of Nokia called HERE is now collecting this type of data across the country for use in car-navigation systems and online applications like Yahoo Maps and Bing.
But in New Orleans, the company handed over its raw data from four historic areas — the Garden District, Faubourg Marigny, the French Quarter and Esplanade Ridge — to CyArk. The nonprofit’s technicians then uploaded the data into computer-aid drafting software and began stitching the images together to create a three-dimensional, engineering-grade blueprint of historic streetscapes and building exteriors in the city.
The images are accurate within a centimeter and are linked with global-positioning coordinates to show exact locations.
Because lasers create digital measurements of buildings, not images of them, the initial results look more like the movie “Tron” than a coffee-table book of New Orleans. So, to colorize the images, CyArk technicians incorporate photos taken concurrently by the cameras that are also fused to the data points.
The scans, when processed, can also create panoramic street-front images that are miles long because the scans aren’t hampered by the elements that usually get in the way of photos — like those pesky live oaks in the neutral ground or buildings across the street that limit how far you can back up.
The nonprofit will now sit down with New Orleans preservation advocates and officials to determine what comes next, said Lee, who suggested that interior scans of the city’s most vulnerable or historic structures might be possible. But more imaginative uses might also be possible since laser cameras don’t need light and can be pointed into holes and crevices to create images of areas beyond human access, like small attics, walls or chimneys, she said.
Beyond its work in New Orleans, CyArk has teamed up with commercial and academic partners to scan 500 historic sites around the world. So far, its archive includes roughly 100 sites, including the ruins of Pompeii, the wreck of the Titanic, Cambodia’s Angkor Wat temples, Easter Island’s statues, the Sydney Opera House, Mount Rushmore, the Leaning Tower of Pisa and the Tower of London.
Lee said the goal is not only to capture the images for posterity but also to assist with rebuilding if a cultural treasure is lost, which has already happened twice with sites CyArk had recorded: a 600-year-old wooden city gate in Seoul, South Korea, that was destroyed by an arsonist in 2008 and the Royal Tombs of Kasubi in Uganda, which have been hit by devastating fires in 2010 and 2012.
CyArk itself was formed in the wake of a similar catastrophe. Ben Kacyra, a retired civil engineer, and his wife, Barbara Kacrya, have said they were spurred to create the charity after the Taliban’s 2001 implosion of the 1,500-year-old Bamiyan Buddhas in Afghanistan.