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Group using 3-D scans to digitally preserve California's missions

Crews from an Oakland-based nonprofit called CyArk are mapping the fragile structures so that they can be accurately rebuilt in the event of a disaster.

January 01, 2013|By Steve Chawkins, Los Angeles Times
  • At San Juan Bautista, a Central Coast mission founded in 1797, and which was heavily damaged in the 1906 San Francisco earthquake, a CyArk crew spent two days taking millions of measurements from about 180 locations.
At San Juan Bautista, a Central Coast mission founded in 1797, and which… (CyArk )

When the Taliban used dynamite, artillery shells and rocket launchers to destroy two ancient Buddhas in Afghanistan, there was an unanticipated bit of blowback.

The 2001 attack on the Buddhas of Bamiyan also launched an Oakland-based effort to digitally preserve world historic sites, including, most recently, the missions of California.

Using cutting-edge 3D scanning technology, crews from a nonprofit called CyArk have wedged themselves into seldom-seen spaces in four of the state's 21 missions, bouncing 50,000 laser beams a second off centuries-old timbers. The idea is to map the fragile structures more precisely than they've ever been, creating virtual 3D models accurate down to millimeters.

PHOTOS: Scanning California missions

Even if earthquakes or fires were to devastate them, detailed plans for rebuilding would be just a mouse click away, said CyArk's founder, a retired civil engineer named Ben Kacyra.

Kacyra, 72, helped invent a portable 3D laser scanning device, paving the way for the technique's use by architects, urban planners, video-game designers, road builders, homicide detectives — a wide variety of professionals who need quick, meticulously detailed views of complex scenes.

After Kacyra sold his San Francisco Bay Area company in 2001, he and his wife Barbara started what he calls "a foundation to do good." About that time, Afghan fighters turned the Buddhas — the larger one was 18 stories high and nearly 1,500 years old —into rubble.

Kacyra was appalled.

"It was so vivid," he said in an interview. "This was a concentrated effort to destroy history by people who didn't agree with it."

As a boy in Iraq, he had been awed by the ancient Assyrian statues of winged bulls at the ruins of Nineveh, in his hometown of Mosul. Now, struck by the fragility of history, he vowed to preserve what he could — in 3D.

That's how Justin Barton, a 31-year-old CyArk archaeologist, recently came to be climbing a scaffold in a narrow space behind the altar wall at Mission San Juan Bautista, peering out at an empty sanctuary from behind statues of saints. Weeks earlier, he had returned from the Eastern Qing Tombs in China, a mausoleum for emperors and their concubines. In 2010, he was part of a crew dangling cameras and scanners off Mt. Rushmore to capture tiny details of the presidential visages.

"I spent a lot of time there processing data on the ground," he said. "I could tell our rope teams, 'I don't have Jefferson's left eye, or we need more under Roosevelt's chin.' "

At San Juan Bautista, a Central Coast mission founded in 1797, Barton and a CyArk colleague spent two days taking millions of measurements from about 180 locations, including a choir loft that tilts 10 degrees and a cramped attic accessible only with a shaky two-story ladder.

The mission is perched on the San Andreas Fault. In 1906, the earthquake that devastated San Francisco damaged much of the church. The side aisles were buried under rubble and finally reopened 70 years later.

"The fault line is just about 40 or 50 feet away, down a little slope," Barton said. "San Juan Bautista is a poster child for exactly why we're doing this."

In the 1930s, the federal Historic American Buildings Survey sent in workers equipped with transits and tape measures, said Ruben Mendoza, a parishioner who teaches archaeology at Cal State Monterey Bay.

With the new survey, engineers will see just how much more the choir loft has tilted and just what should be done about walls that are slowly collapsing and a chapel archway that's cleaving open. "We're in absolute need of triage," Mendoza said, "and this effort will help us get there."

In Carmel, the laser scanning has been "just a godsend for us," said Warren Hoy, a mission deacon. Until CyArk scanned the intricate wooden latticework holding up the basilica roof, nobody knew about the weakness of some hand-hewn beams, Hoy said.

"It's really hard to crawl around up there, and previous measurements weren't precise," said Hoy, a spokesman for the Diocese of Monterey.

With each beam irregularly shaped, the more precise data allowed officials to order pre-cut steel braces that fit exactly — a complicated process that could have been much more expensive and entailed peeling off the roof, according to Hoy.

The laser surveys started last summer at Mission Dolores in San Francisco and Mission San Luis Rey in Oceanside.

In San Francisco, CyArk's cameras captured images of a Native American mural painted between the mission's completion in 1791 and the 1797 installation of an elaborate carved reredos, a wall-size altarpiece.

The mural's mix of Christian religious symbols and native designs has been hidden from view just 2 feet behind the reredos, said Andrew Galvan, the mission's curator and the descendant of an Indian man baptized there in 1794.

"We've known about it, but we haven't had a way to display it," he said. "Now CyArk is going to make it possible. We're even working on a phone app."

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