Arts: It only takes a minute

It is a scene so strange and quietly intimate that it is easy to forget the eye of a lens is watching. The man sits naked on a stool, sideways on to the viewer, his penis cradled against his stomach. His head is covered in plaster of Paris, and above him, a shelf carries other models of his head - one with a pair of antlers attached to it. Behind him, a woman in overalls is walking out of the door carrying a tub for more plaster. The atmosphere is not that of a freak show - quite the reverse: it is one of emotional and artistic collaboration.

Antony Gormley, 1994 Turner Prize winner, and his wife, Vicken, did not pose for this portrait. The mood of the picture conveys this, even though the artificial elements in the composition of the piece seem to claim otherwise. How else could there be that perfectly balanced contrast between her dark-haired profile moving towards the left of the frame, and his white-plastered head gazing blindly to the right? Or the direct echo between Gormley's featureless mask and the skull-like model of his head on the shelf above him, also pointed to the right of the picture? Ask the photographer responsible, and he will shrug his shoulders with a self-deprecating grin and say that it just happened. Paradoxically, the pose is an accident.

Welcome to the curious meditative world of Gautier Deblonde, the man who has absorbed the philosophy of Cartier-Bresson's "decisive moment" and has brought it to the portraiture of more than 70 artists who are well known in Britain. Over the past six years, Deblonde has cultivated painstaking relationships with these cultural icons, spending weeks discussing the nature of each one's art and observing them at work, before ambushing the instant summing up their life. The list of those who have chosen to respond to his photographic advances features an eclectic range of personalities, from Gilbert and George, David Hockney, Bridget Riley and Eduardo Paolozzi, through to Rachel Whiteread, Sarah Lucas and Tracy Emin. The resulting images reflect this diversity; but while it is easy to be surprised at the number of different ways in which he makes his subjects' personalities shine out from the photograph, when you first look for Deblonde's defining features, he - rather like TS Eliot's Macavity - is not there.

Part of this is due to Deblonde's refusal to impose any methodology on his portraiture. It is a technique that he admits can sometimes lead to tricky moments with his subject. "I never come to a place with an idea of what I really want to do - and sometimes I feel really embarrassed, because I'm turning around and trying different things, and I'm worried that people notice I don't know what to try next." Chris Ofili, the 1998 Turner Prize winner, puts a more positive spin on Deblonde's words. "He doesn't have any ideas beforehand, but that's the most exciting way of approaching a subject. As a result, where other portrait photographers' images can simply skim the surface, Gautier manages to fly below each individual's radar."

Deblonde eventually managed to get though Ofili's defences, late one night after the artist had finished work at his King's Cross studio. After taking a walk round the area they returned to the studio, where the artist sat on a chair next to a light he had been projecting on to the wall. The result defies cynics to believe it wasn't set up - we see Ofili himself to the left of the picture, while his looming black silhouette, which dominates the portrait's central space, seems to juggle with playing-card symbols of spades on the right. But the image which digs under his character and plays so confrontationally and symbolically with Ofili's blackness was the result of elements "just there" in the studio: the spades were part of a painting Ofili was working on at the time, while the lighting and the chair were normal accessories to his work.

It is perhaps arguable that Deblonde's subject matter, as well as his patience, gives him the advantage for such happy coincidences. Dealing with artists surrounded by their work, he is more likely to seize on visually interesting symbols of their obsessions than when portraying people in other walks of life.

Deblonde himself has an obsession with the way artists create, saying: "Sometimes the process is more interesting than the final work. There is something very special about going into an artist's studio for the first time." When I try to swing the lens round on Deblonde, asking him how he would do his own self-portrait, it is typical of his diffidence that, when he answers, he has placed himself once more behind the camera. "I'm somebody who's very shy, very quiet - and I think this shows in my pictures. Some of them are looking at me from the side; in one picture I am behind my subjects - I try to be there without being too much in their face." Richard Wentworth, whose show Thinking Aloud is now at the Camden Arts Centre, agrees with this, describing Deblonde as being "gently present... And he's also very anxious. But it's not the kind of anxiety that pisses you off."

Getting to know Deblonde's photographs is not unlike getting to know a shy person: after a while, subtle qualities come to the foreground - and these ultimately rank him among our leading photographers. There is his ability to make inanimate objects - such as suspended books, chunks of wood, or manikins - look alive, or his tendency to bisect pictures into chunks of dark and light in a way that adds to the sense of a character acting within a space. I comment on the irony that as a shy person, he has worked with the kind of individuals most confident people would hesitate to approach. Deblonde laughs, shrugs his shoulders, and replies: "That's why the whole project took me six years.'

The images are taken from `Artists', Tate Gallery Publishing, pounds 14.99