"Anything and all things are photographable," said Winogrand, who trawled the streets in search of images that encapsulated his time. The anonymity of city life is writ large - everyone goes about their everyday business, occasionally stopping to gawp at their fellow citizens but rarely going so far as to interact: one old man, laden with dry-cleaning, stoops to retrieve his walking-stick with no offer of help from passers-by.

"Anything and all things are photographable," said Winogrand, who trawled the streets in search of images that encapsulated his time. The anonymity of city life is writ large - everyone goes about their everyday business, occasionally stopping to gawp at their fellow citizens but rarely going so far as to interact: one old man, laden with dry-cleaning, stoops to retrieve his walking-stick with no offer of help from passers-by.

The Man in the Crowd: The Uneasy Streets of Garry Winogrand, on show at the Photographers' Gallery, is the first exhibition in a series entitled the Altered States of America, which examines the multifarious faces of post-war America. Fashion and politics rub up against each other, as Winogrand records the bouffant hairstyles and tiny miniskirts of his day, alongside the large, vociferous crowds of the anti-Vietnam war demonstrations and women's-lib marches: a fascinating window into history.

"I like to think of photographing as a two-way act of respect," said Winogrand, who died in 1984. "Respect for the medium, by letting it do what it does best: describe. And respect for the subject, by describing it as it is. A photograph must be responsible to both."

All the images in the Winogrand show are small, grainy, black-and-white and taken at street level, with the camera often only a hair's breadth away from its subjects. Here is a voyeur who likes to get into the thick of things, conveniently camouflaged by the bustle of his native city and adept at snapping those around him without their even noticing him or having time to become self-conscious.

In deliberate contrast, the large, colour photographs of the German photographer Karin Apollonia Müller take a firm step back. Urban life is recorded from on high and far off. The cityscape is no longer just a backdrop to the colour of everyday life: it is everything, almost crushing the life out of any the citizens who inch their way into the frame.

Müller, who lives and works in Los Angeles, presents the city as an indifferent, alienating environment, in which the balance between urbanisation and people and nature is unfairly weighted in favour of the skyscrapers and speeding traffic.

In one image, a tiny figure lies sprawled on a grubby piece of wasteland, frighteningly vulnerable - protected from the elements by a scrap of orange plastic sheeting. In Downtown III, LA (1997) the parking lot, freeway and high-rise rule, while a stooped figure carries what appears to be a rolled-up carpet or mattress. "Need Knows No Season" and "People Count" exclaim two billboards in the distance - a plaintive cry that Müller clearly feels needs to be made.

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