In 1961, Richard Avedon photographed Sophia Loren for the cover of Harper's Bazaar. He surrounded her with a retinue of dressers, shoe people, makeup artists and a milliner, who crowded the shot and framed Loren, the still, elegant star who appeared oblivious to them all. It's a witty and pleasingly dated image, one of the first things one sees at a new exhibition at the Photographers' Gallery in London.  In the early 1960s, fashion photography began to turn to itself as a subject, to its own artifice and staging; fashion photographers became an ever more visible presence in their own work, as well as iconic figures in popular culture, louche and stylish. Norman Parkinson steadied his tripod with one stockinged foot as he shot his model, and himself, in a 1962 image for Queen magazine. The photographer Melvin Sokolsky, taking the part of Velázquez, stood in the shadowy background with a dog and an assistant, as he shot a model in a flowery dress in Las Meninas, Isabella, Me, Nick. Just as Velázquez painted himself in the act of painting, so fashion photographers have put themselves in the picture. Sometimes this leads to interesting images. Sometimes it is only a matter of vanity. Rarely is it a deconstructive, critical act. This is the world of fashion, after all.  But fashion is also theatre, a world of make believe, and there is nothing more theatrical than revealing the layers of artifice that construct an image, especially when it is done within the image itself. It is like the conjurer's reveal. Sometimes this can be very discrete: two of the earliest images in this show, by Irving Penn and John Rawlings, do little more than pull back from their subjects to reveal the edges of the stage backdrop, the world beyond leaking in.  Bert Stern's shot of David Bailey, who has flung himself to the ground in a paroxysm of enthusiasm while firing off a roll of Veruschka (who steps between his legs and, so it seems, prepares to kick him in the balls), is a take-off of Stern's own propensity to lay on the floor to photograph his models. Nick Knight, in a 2003 Vogue shoot Flash!, plays around in a corridor of infinite reflections, all done with mirrors and foil. Knight's angular and self-conscious posing among his models wants us to recall Parkinson and Bailey, but this stilted self-choreography looks strained for.  Almost nothing here can compete with Helmut Newton. In his Self-Portrait with June and Models, Newton aims his camera past a naked model and into a tall mirror where she is reflected. There are five people in this 1981 image, shot in Vogue's Paris studio, not counting the man in the car, who we see through an open doorway on to the street. First there is Newton, in raincoat and plimsolls, and the model herself, both of them reflected in the mirror. Much closer to us, so much so that she is somewhat out of focus and cropped at the knees and shoulders, is the model again, seen from behind. Between this standing nude and her reflection is a second model, seated. All we see of her are her knees, calves and feet, wearing a pair of extremely high heels. It is as though these legs could make up for the part that has been cropped from the other model. To the right of all this, is Newton's wife, June, observing the scene. She, too, is a photographer, but today she is just looking.  The longer I look at this photograph, the more mysterious the image gets and the more questions I have. It's a scene drilled with gazes. Your eye goes between the people and into the shadows, and from things seen to things imagined, and eventually you're led through the door, to imagine what it would be like to be the guy in the car, turning and looking in for a second as he passes by.  Newton's genius lies in knowing what not to control, in always keeping a door open. He was a marvellous and troubling photographer. There is also a photo spread assignment for Nova magazine in 1971 here, shot a year after Newton had a heart attack. Called Caught Underwears, the framed spreads show him alone in a cramped hotel suite, with a mirror on the ceiling over the bed. Newton and his model collaborated in a number of scenes in which both photographer and model are seen in this overhead mirror. In one shot, the naked woman lies on top of the photographer, who is dressed all in black, accenting her nakedness. We can't see his face, just his hand squeezing the bulb of the cable release, and the camera on its back on the bed. The camera sees it all.  The blurb accompanying these Nova spreads talks about underwear and what men might find sexy, but it hardly matters. All one concentrates on are the photographer and his model. This sequence made me think of a series Juergen Teller shot with Charlotte Rampling a few years ago, in an altogether more luxurious Paris hotel suite - both of them in the frame, naked and clothed, playing an intimate game. In Teller's single photograph in this exhibition, of Vivienne Westwood holding an axe, it looks as though she has murderous designs on him.  There are perhaps a dozen strong and interesting images here: the rest are product. Playing up the artifice of the fashion shoot, turning the whole thing into self-parody is all very well; sometimes, depending on the photographer and the situation, something extraordinary happens. But, equally often, the results can be grim. Steven Klein describes his 2005 Valley of the Dolls series as a kind of science fiction novel, "as if written by Joan Didion". In his dreams. Klein's images lack anything that might compare them to Didion's tough, electrifying prose. Artificially bronzed, bleached and cloned musclemen inhabit an incomprehensible world. There are female prosthetic mannequins and some business in which the designer Tom Ford buffs a man's bottom with a power tool normally used for putting a waxy shine on automobile bodywork. The whole thing is dumb. I felt the same about Jonathan de Villiers shot-of-a-shoot on a beach in Mauritius: it's just a bunch of swimwear snaps that might as well have been done in a studio in Fulham. Maybe that was the point.  In Steven Meisel's 2007 Vogue Italia series, Super Mods Enter Rehab, smacked-out-looking models are dragged along institutional corridors by aggressive orderlies, take therapeutic baths (though so zonked are they, they've forgotten to undress), hang out in their locked-ward dormitories, and generally do their careers no self-harm whatsoever. Previously, Meisel has had models play at Homeland Security narcs and terror suspects. I doubt these mockumentary images are intended as social commentary, or as a lacerating satire of the fashion industry's atmosphere of vacuous complicity. They are too much part of the game, too locked in the same hall of mirrors. Of course, staged and contrived situations are also real - in that something is always happening beyond the storyline and the set. Most of the photographers here just aren't interested enough, or clever enough, in getting to it.  · Fashion in the Mirror: Self-reflection in Fashion Photography is at the Photographers' Gallery, London, until September 14. Details: 020-7831 1772.
Who's in charge here - model or photographer? Adrian Searle on manipulation and make-believe in a new exhibition of fashion photography