Craig Winslow is a Portland designer who moonlights as a ghost hunter. Only, the spirits he's chasing are definitely real—and they exist in plain sight.

Before the introduction of large-scale vinyl printing in the 1960s, advertisements were often painted on the sides of brick buildings. Some featured big brands like Coca-Cola, others promoted local businesses that are no longer around. Today, they're called "ghost signs," and many are still there today—a bit faded and becoming more so by the day.

"It's something you don't see until someone points it out to you, and then that's all you can see," says Winslow, 32. "They're hidden so often right on streets you walk around all the time."

Winslow has spent the past six years preserving over three dozen of these signs in Portland and around the globe. He does so through a process called projection mapping: stitching together high-resolution photos of the ghost sign in Adobe Photoshop and then tracing by hand to reveal the ad's lettering and details. An animation of the faded ad can then be projected onto the wall where it made its debut.

Winslow's ghost sign installations used to be one-time, on-location experiences. But next month he plans to launch an app called Light Capsule that uses augmented reality to give users a chance to see these old ads revived to their original glory right on their smartphones.

"Imagine you're walking in downtown Portland, and you get a notification that you're nearby one of these signs," Winslow says. "You open the app, aim your phone up at it, and your phone then becomes a lens into the past."

Cataloging and digitally restoring ghost signs is a passion project for Winslow, and so far he's resurrected advertisements for Portland clothier Sam Moy & Co., an Overland Cars dealership, and Dillen Rogers Jeweler & Optician. What drives him is knowing that one day ghost signs won't just be faded, they'll be indiscernible. There is currently no method to physically preserve them, and most historical societies don't keep records of advertisements.

"Some of these are about to be lost and can't be re-created," he says. "It's exciting to feel like I'm able to bring back some of these lost stories."

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