Vineyard Haven native Marshall Pratt recently sold just over 20 photographs to the Boston Athenaeum, an achievement made all the more impressive by the fact that the photographer is just over 20 years old.

Mr. Pratt is a junior at the School of the Museum of Fine Arts in Boston, where he studies photography. The work acquired by the Athenaeum is a collection of prints that depicts areas of Greater Boston that have become derelict or otherwise suffered the effects of poverty, cultural isolation and neglect.

According to curator of prints and photographs Sally Pierce, these areas are underrepresented at the Athenaeum, whose collection has historically been particularly strong in views of Boston and New England. The acquisition of Mr. Pratt’s work strengthens those views, broadening the perception of what’s picturesque in the city’s environments.

Mr. Pratt considers himself to be a documentarian. His photography is an extension of that duty, he said, and is his primary medium, but he also makes use of print-making and collage. The latter often involves found objects, which, according to Mr. Pratt, “are just as reflective as a photograph, as a document of time and space.”

Mr. Pratt prefers not to deal too heavily in the conceptual when documenting his subjects. “My work, it’s not overly heady,” he said. But he does operate from a particular perspective: that of an Islander.

“Martha’s Vineyard is an Island, sure. But so is everywhere else. The Vineyard is bordered by water, but it’s also bordered by other things. There are always borders, outer limits, to every zone, whether they be geographic, economic or fear-based. People make these designations for themselves.”

The centerpiece of the portfolio Mr. Pratt sold to the museum is a triptych entitled Wonderland that features both photographic prints and collage. Mr. Pratt calls it a “collaged response piece.”

“I had an urge to find a place in Boston that smelled like home. The closest thing I found was in Revere, which is the seaside, but very different. It was that experience that spawned the concept that you don’t have to be around water to be on an island,” he said.

The Wonderland series was shot in December of 2007, and led directly to the series of work that comprises the bulk of Mr. Pratt’s sale to the Athenaeum: a 20-photograph series on Wan’s Convenience and Deli at Roxbury Crossing. Two blocks away from Mr. Pratt’s apartment, the store became his subject after the photographer became a regular and found a thriving microculture existing there. “It’s a real down-home place. A real island within the city,” he said.