By Lana Bortolot

New York has no shortage of “urban archaeologists” who, motivated by a love of their city and what they see as its vanishing profile, are rushing to document its history.

Mark Abramson for the Wall Street Journal
Frank Jump points to a ‘ghost ad.’

This month, two such hobbyists join that merry band with projects that focus on the city’s public graphics. The works capture two aspects of New York’s signage: hand-painted display advertisements, familiarly known as “ghost ads,” and their higher-tech cousins, neon signs.

Frank Jump, a teacher at P.S. 119 in Flatbush, began his “Fading Ads” campaign in 1997 as a creative outlet, and then embraced it as a metaphor for his life as a person living with HIV. He said the ghost ads mirrored the potential fading of his own life as he underwent medical treatment, which included chemotherapy for rectal cancer.

“Like myself, many of these ads had long outlived their expected life span,” he said. Mr. Jump, now a 10-year cancer survivor, said his HIV has stabilized. And now his project also has some permanence. This month, the History Press published “Fading Ads of New York City,” a collection of 80 hand-painted ads that, though distressed, still telegraph bits of the city’s vibrant commercial history.

Using 35mm Kodak chrome film, another homage to something lost, Mr. Jump, 51, shot more than 5,000 images throughout the boroughs, seeking out the trappings and the trimmings of an earlier time—elixirs, fancy foods and fashion accessories.

“These images tell the story of the human body as it travels through the urban landscape,” he said. “If you’re in pain, there’s a sign that will beckon to you, if you’re hungry, there’s a sign that claims to take care of that.”

Mark Abramson for the Wall Street JournalKirsten Hively near some of her subject matter, neon.

The adverts also signal commercial and ethnic movement throughout the city and provide quick hits of history, said Kathleen Hulser, a historian at the New School’s Eugene Lang College.

“They give people a casual and easy reminder of the history that’s around us, and you can come across it in a spontaneous manner,” she said. “The streets are alive because of this consumer culture overlay—you didn’t even have to buy anything to be stimulated by it.”

Steven Heller, who teaches graphic design at the School of Visual Arts, said the ghost signs add a patina to the streetscape.

“That’s what’s lovely about them—they do indicate where there were centers of industry or trade,” he said. “That’s the city history and the typography history and the commerce part of it, and the combination of that is what’s fascinating to people.”

Mr. Heller acknowledged that the signs, which occupy valuable real estate, exist only at the benevolence of building owners. “If you were to preserve a ghost sign on the side of a building and someone has air rights—what goes first?” he said. “In the long run, it is a piece of faded paint.”

Without them, “the individuality of New York City would suffer” said Kevin Walsh, author of “Forgotten New York.”

Looking on a brighter side of things is Kirsten Hively’s Project Neon: an online archive of some 600 mostly vintage neon lights throughout the boroughs. Ms. Hively, 40, began the project during a break from her architecture career last year, turning it into a full-time endeavor upon receiving enthusiastic response from her Flickr group.

This week, she presented her work in a slideshow sponsored by the preservation group LandmarkWest!. It was an extension of her show at Williamsburg’s City Reliquary. In addition, she recently launched an iPhone app mapping some 115 neon sites.

“I think of it as urban design—the sort of life and color and shape of the urban environment that we all share,” she said. “One thing about neon is that its high point is recent enough that it’s not yet in our history. I think it falls in that crack between history and contemporary.”

But vintage neon is becoming a thing of the past, as it is increasingly replaced by digital technology.

“It’s become the poster child for appreciation of the vanishing city,” said Tom Rinaldi, author of the forthcoming “New York Neon,” a scholarly look at the gassy signage.

Both Ms. Hively and Mr. Rinaldi cite Colony Records’ jumping girl (1619 Broadway) and the harp at Dublin House Tap Room (225 W. 79th St.) as glowing examples of Manhattan’s most iconic neon. They also praise the less flashy—such as at Sardi’s—and the flashers, like Peep-O-Rama, the last such sign on 42nd Street, now housed in the Times Square Visitor Center.

Ms. Hulser says neon’s contribution to the visual landscape is cultural as well as colorful.

“It was kind of fabulous because it contributed to the 24-hour city,” she said. “The areas that were lit at nigh …said, ‘Here is a place for the people who cannot sleep.’ So it became an iconic way of signaling this is a culture of energy and people like that can find themselves here.”