Photographs relate history in two ways: through the subject matter inside the frame, and the voice of the photographer framing it. Is that voice empathetic or cautionary? Does it probe its subjects or linger objectively on their surfaces? In the late 1940s and 1950s, a small number of photographers from the Magnum agency turned their cameras on New York, capturing both the changing city and the changing role of the image in its residents’ lives.

“Photography used to be thought of as a quasi-objective medium,” simply transferring the world onto paper, said Fred Ritchin, dean of the school at the International Center for Photography. “With Magnum in that period, what you see is photographers gaining the autonomy and independence to show things the way they saw them.”

“Early Magnum: On & in New York” is an exhibition that will be shown at the National Arts Club and on the agency’s website starting March 27 as part of the agency’s 70th anniversary program. The exhibition shows a city not quite visible to the naked eye: alternately pensive and quick to fight, a place where people disappear in crowds or seem exposed when they’re alone. Just a few years before, photographers had brought home images of devastation from Europe. Now they found a city bursting with new life.

“They’re pictures of hope and of vision,” said David Kogan, Magnum’s executive director. “There’s a sense of romance so different from the war photographs.”