Striking the impossible balance between truth and beauty was the utopian goal of the Photo League, a confederation of photographers formed in 1930s New York. These mostly Jewish leftwingers took up the burden of social improvement but resolved to carry it with élan. “Upon the photographer rests the responsibility and duty of recording a true image of the world as it is today,” the founders solemnly declared in 1938. But they felt just as strongly that a picture could be a story and a poem, factual and exquisite at the same time.

A wonderful exhibition at New York’s Jewish Museum testifies to the elusiveness of their goals and the astonishing successes they achieved. The Radical Camera doesn’t hide some occasional failures. At times, politics or formal fussiness blunts a picture’s forcefulness. But the show also boasts more than a few stunners, and it mines a delicate moment when the ideological dogmas of the Depression yielded to the expressivity of the postwar years. Lou Bernstein’s “Father and Children, Coney Island” (1943), a picture of a black family at leisure, belongs only superficially to the Works Project Administration tradition of essays on racial dignity. Shot from above, the man and his toddlers sprawl in an undulating calligraphy of bodies, and the intimate energy of their relationship ripples out into the blanket and sand. The interplay of love and line is the quintessence of the Photo League’s mission.

Even as the group’s members loosened the soil around their leftist roots, they never gave up their intense, humanitarian focus. “There is no use to being a photographer if you are not inherently a tremendous social person,” said Sid Grossman, who functioned as the congregation’s secular rabbi. “And this holds true no matter what area of the world you deal with photographically. You must need to be outside yourself, and you must need to show this to other people.” Grossman uttered these words in 1950, a few years after the calamity of McCarthyism tore the Photo League apart. The government deemed it “totalitarian, fascist, Communist or subversive”. Grossman was specifically fingered as a traitor and he was thrust from the organisation he helped create.

His brief but exhilarating career encapsulates the fortunes of the whole group. He began his tenure at the league as a proud communist intent upon exposing the working man’s virtues and tribulations. A 1939 picture of two plaintive shoeshine boys on a Harlem street corner (not in the current show but reproduced in the generous catalogue) fits into the documentary framework forged by Lewis Hine and burnished by Dorothea Lange, Ben Shahn and Walker Evans. Like those pioneers, Grossman and his colleagues sought out temporarily downtrodden but dignified subjects, victims of oppression and exploitation who could be lifted up by a dose of empathy.

In the early years, Grossman – known then as “the Commissar” – came down hard on colleagues who aestheticised their material. Harold Corsini’s bird’s-eye image of boys playing football in the street comes straight out of European “New Vision” experimentalism, seizing a surprising vantage point to capsize our sense of how things should look. Aaron Siskind’s “Market” (1937), also taken from above, employs oblique angles and sharp contrast to upend our perceptions and point us towards the shot’s graphic qualities. Grossman dismissed these efforts, advocating instead a strict realism of the kind that was being enforced by diktat all over Europe. By then, Stalin had suppressed the Russian avant-garde and the Nazis had shuttered the Bauhaus. But Grossman’s shoeshine boys suggest he didn’t fully believe his rigidly articulated principles: even this strictly documentary photo vibrates with a tracery of shadows, perspective lines and intersecting diagonals.

Grossman gradually overcame his dogmas. Stationed in Panama during the second world war, he composed a series of night scenes infused with hallucinatory movement. He blurred them intentionally, expressively, substituting fragmentary moments of human grace for the old parables of class and money.

Sid Grossman, Coney Island (c.1947)

Eventually, his attitude executed a 180-degree turn. Where once he believed that photographs should enshrine Marxist revolution, after the war he argued for a permanent state of revelation. To become a photographer, he insisted, “involves a completely new attitude towards the people you are dealing with, towards everything you do in this world ... You live by gyrating.” The virtuoso uses the camera to keep meeting the world afresh, to notice the unexpected and strip off encrustations of visual habit.

In the years after the war, other members followed Grossman away from preachiness. Leon Levinstein shoved his camera so close to strangers’ bodies that he lopped off arms, legs and faces. All that’s left is a brutish sense of bulk and movement. He tackled the “Brooding Man” from below; an amorphous expanse of jacketed arm oozes across the page, obscuring everything but a lurid slice of cratered face and a disembodied hand. Unlike Grossman, Levinstein was a cold observer with a keen sense of composition. He only cared about people as performers in his private dance of rage.

Dan Weiner sublimated leftwing leanings into sublime irony. The wall label suggests we see “Women at a Perfume Counter” as a critique of the consumerist tendencies of the postwar years. A flawless salesgirl elegantly tips back her head as she squeezes a puff of scent at her dowdier doppelgänger on the other side of the counter: she is the siren of frivolity seducing American womanhood. But the vignette also offers a more open-ended meditation on youth and age. The figure in clearest focus is a tiny older woman who refuses to be overshadowed and stares distrustfully at the fragrant proceedings. She, at least, seems to know a hard sell when she sees one. One disapproving purse of the lady’s lips contains all her disdain – or is it envy? – of the youngster’s hope and folly. From this one mundane instant, Weiner has extracted the full spectrum of the Photo League’s contradictory concerns: politics, currency, momentary truth and the timeless interplay of passions both petty and grand.

‘The Radical Camera: New York’s Photo League, 1936-1951’, Jewish Museum, New York, to March 25,

View a slideshow of photographs in the exhibition

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