Super Mario - he's picture perfect

Mario Testino, that famous fashion photographer from Peru, never makes the mistake of holding a mirror up to nature. His lens instead is a successor to the looking-glass in Snow White, the one that tells people they're the fairest of them all. Gwyneth Paltrow declares that Mario's pictures connect to "the truest and lightest aspect" of herself. Kate Moss, to whom he restored curves after her unfortunate dalliance with heroin-chic, commends him for divining her sexiness. Five months before she died, Mario delivered flattery's greatest coup of all, turning the anguished, newly divorced Princess Diana into the very image of a carefree cover model, a throat-back, laughing, queen of hearts.

Now an exhibition of his work is to open at the National Portrait Gallery. Inside its halls, his wizardry will posthumously amend the royal fairy tale by photographically reuniting Diana with her former husband, whom he has snapped in domestic bliss and an old Nepalese coat, feeding his chickens.

"So friendly, so funny," Testino clucks. "Prince Charles really struck me as a very witty, joyful person, somebody that just loves having a good laugh." The National Portrait Gallery knows all about the tradition of sycophantic portraiture. Doubtless, Joshua Reynolds's agent would have sold his wares to Vogue and Glamour had they been around. But Testino's photographs sprinkle fairy dust over everything. In his occasional forays into reportage, even priests and soldiers assume a skittish air. On next week's BBC Omnibus tribute, Tom Ford, the creative director of Gucci, enthuses: "Wherever Mario goes he has a great time. And you have a great time being with Mario."

The first thing, then, to report about my visit to a voluminous studio in Kensal Green, where Mario is at work, is that no one seems to be having a great time at all. His assistant Sabrina is stressing out on a mobile phone. A model is lugging her suitcase upstairs unhelped. A young man, urgently on the go, slurps cornflakes standing up. Behind the closed doors, where Testino is photographing the artist Angus Fairhurst, there may very well be nirvana. Outside, all is Pre Mario Tension.

When, however, he eventually enters the room where I've been parked, the very air molecules relax. A paunchy 47-year-old with almond skin, thinning hair and miraculously white teeth, he reminds me very slightly of the late comedian Bernie Winters. He is even dressed as Bernie might have been: blue shirt, blue jumper, old Levi's. Soon he is schmoozing me with jetset accomplishment. "Your tie iz incwedible!" he says, and I note that the trick of his flattery is that he manages at the same time to be - and here the comparison with Winters breaks down - funny.

"Wow, you have a good-looking girlfriend! Beautiful eyes!" he exclaims when I ask him to critique some recent retrievals from Snappy Snaps. "What did she see in you?"

The problem accepting praise from Testino is that praise is all he ever delivers. I remind him that he once boasted that he had never photographed anyone in a negative way.

"Well, I like to make people feel good. It's funny because sometimes people who interview me say, 'So how do you feel about being the happysnappy photographer?' and the truth of the matter is it's so hard to do happy-snappy photo that looks like you haven't done anything at all."

To have achieved such spontaneity from Diana must have been nerve racking? "And I go through that whole process inside of me without telling anybody. I go through the whole insecurity and anxiety."

He just wanders in and everybody thinks he's charming Super Mario? "Yeah, 'He's so easy' and 'He's so relaxed'. It's never like that inside, but obviously you can't show it to people. It's like you go to a doctor. I think we're like doctors a lot of the time, because people come to us with problems. How do we sell this? How do we show this? At the end of the day my job is to sell. I have to get people to go from their homes and buy."

Magazines, dresses, handbags - one safely anonymous fashion editor called his work "the apotheosis of shallowness". I ask if he does simply record the surfaces of people or if, as his subjects prefer, he mines their essence? He replies that anybody can photograph surfaces and thousands of photographs of Cindy Crawford, Claudia Schiffer and Linda Evangelista reveal no trace of who took them. "To make a portrait yours you have to bring something out from the inside that they will not give to other people."

But aren't these models superficial all the way through? "A lot of them are, yeah, but a lot of them aren't. I think that the ones that really get to the top, they have to be pretty clever."

Who's the cleverest? "Well, I love Kate Moss. That's my favourite of them all, just because she's got that thirst for life that I so like."

Is her cleverness intellectual or instinctive? "I think she's instinctive but I'm not an intellectual either, and I don't think I'm stupid."

He is not. Before taking up photography in 1980, he studied economics, law and international relations at three different universities. Nor does he take stupid pictures, just ones that see the world through a haze of naturally occurring Prozac. I make no Testinosized claims about extracting the essence of my subjects, but my working assumption is that the inner Mario must be less deliriously exultant than he makes his subjects. He is a successful man certainly, but he is also 47 and single, despite having had, he assures me, partners of both sexes (Omnibus even interviews an early girlfriend). Last year he spent only 32 nights in his flat in Notting Hill. Home is generally tonight's five-star hotel. This is, he says, his sacrifice.

He was born in Lima into a prosperous, Spanish-speaking, Catholic family. Sent to the city's American school, his first ambition was to be a priest and when he arrived in London in 1976, aged 21, he confesses some Romish taboos remained. By the end of the Eighties, however, he had shed enough of them to have compiled a portfolio of male nudes.

"I called my first book Mario Testino: Any Objections? because I felt people had this idea of me as being good, elegant. I brought out beauty. All that. But I'm not just that. I have a lot of me that is dirty and seedy and I like sex like anybody else. I'm a voyeur. I don't think I am really like a goody-goody person."

If he has really jettisoned his hangups, why in interviews over the years has he been so reluctant to own up to his bisexuality? Do vestiges of Catholic guilt linger? "God no. I'll do anything. If I feel like going to bed with whoever, I'll go. That's not my problem. My problem is that I don't like labels."

Does he perhaps fear being trapped, settling down and falling in love? "No, I don't really have a fear about that. I mean, in my life it is difficult to juggle a relationship because I travel so much."

The extrovert, air-kissing medium in which he thrives is, I suspect, a highly effective antidote to loneliness. It also grants him honorary status as a beautiful person, countering any black propaganda coming from his shaving mirror. (Not all those blinding teeth are his own, he admits.)

"I grew up in a society where beauty is really important. They judge people on their looks in South America. It's amazing because I never actually realised until lately that it all comes from there and I am obsessed with it."

Teresa, his mother, however, ensured he never mistook himself for handsome. "I grew up with a sister who was gorgeous and I was considered the ugly duckling. My mother said to me as a kid, 'Don't worry. Man is like a bear, the uglier the better.' I grew up thinking I was a monster."

How terrible! "I think she did it out of pity." But the Testinos had money and Mario travelled. When he reached his teens, his better-looking but squarer schoolmates laughed at his platform shoes, red trousers, pink shirts and yellow jackets, but Mario laughed back because he knew they were just Third Worldies who had no idea how kids in London and New York were dressing. He also divined that true glamour was not about clothes but to do with "wit, taste, money and intelligence". Remarkably, he found these qualities in Jim Callaghan's grey Britain as it blossomed nastily into punk. He found us "sophisticated", and we found him exotic.

"To the English, you know, I am like Paddington Bear. I came from darkest Peru," he says, invoking a second ursine self-comparison.

He was noticed by Lucinda Chambers, now fashion director of Vogue, and his career in magazine photography began, haltingly at first and then, once the fad for grunge had passed and he had found the Testino "look", unstoppably. By 1995, when Ford signed him for Gucci, he was féted as an infallible clairvoyant of trend.

"Wherever I go, wherever I am, in a train or aeroplane, I'm always looking to see if there's somebody incredible. I love the idea of discovering something, finding something. I found that girl Jacquetta Wheeler walking on the street. Amazing! But I also doubt myself all the time. It's not as if I think I have absolute taste and whatever I think's great is great. I doubt every single second of the day everything I do. All the time, I ask everybody, all my hair and make-up people, what they think."

Do they ever say, Mario you've picked a dog this time? "Yes, and I have to fight. I'm like, 'No, try it like this. Try her hair like this. Try her make-up like this', and eventually three months later, when we see her everywhere, they forget that they were against her. They are like, 'We have loved her for years.' An example? "Gisele. When I started working with Gisele nobody wanted her. No editor wanted her. I proposed her to all the Vogues. Nobody wanted her and today she's the best paid model there is in the world."

He recalls that the fashion editor who accused him of shallowness also dismissed him as just being "hot, hot, hot". "I thought that's not a bad thing to be. Thank God for being hot! I've experienced the cold, cold, cold. I tell you it was hard having no work, no money. I was quite desperate. It's been good for me because it's what made me really work and fight. I didn't want to be hungry and I didn't want to be cold."

His life, one understands, has contained almost as much rejection as acceptance. When Gwyneth Paltrow tells Omnibus "he loves life so much" she may not quite appreciate how much for him it has been bordered by death. "I don't go to church. I pray though. I pray alone. I pray constantly. In my life I've had a lot of deaths, probably 12 deaths since I was a kid, from my brother (at 10 from cancer) to my nanny to my father to my grandma, to my uncle, to my aunt, two of my best friends. I've often seen people when encountering death suddenly go, 'Oh God, please help me', but throughout their whole lives they never ever thought of God. And I don't want to get to that point ever."

Andy Warhol, who on a more significant scale than Testino once determined fashionability, was a devout and secret Catholic. The trouble with glamour, even more than with art, is that it is a shifting, unstable, unverifiable commodity. It does not completely surprise me that Testino, who trades so heavily in it, resorts to eternal truths. A future project, he promises, will be on churches. Happy snaps of happy-clappy churches, you can bet, South American churches run like carnivals, toothsome nuns, brazen bishops. But churches all the same.

Mario Testino: Portraits opens at the National Portrait Gallery on 1 February. BBC1's Omnibus programme will be shown next Wednesday at 10.35pm.

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