LOOKING around I see sand, water and blue, blue sky stretching away to the horizon. This is Zuma beach, California, where surfers come to ride the waves. It is also the favourite terrain of the fashion photographer Herb Ritts.

In the Eighties, Ritts made the beach his own. Here he photographed Tina Turner, kd laing, Tom Cruise and every supermodel worthy of the name. Further along the Malibu coast he got Julia Roberts to leap into the water in a pair of Y-fronts.

Ritts was a furniture sales rep until one hot summer day in 1979 when he took some pictures of his friend Richard Gere changing a flat tyre in the desert. Later, Gere's publicist persuaded some fashion magazines to look at his work. Ritts went on to photograph fashion, celebrities and nudes, influenced, he says, by the work of Forties and Fifties photographer George Platt Lynes. Now he is one of a quartet - with Annie Leibowitz, Steven Meisel and Bruce Weber - who dominate magazine photography.

For the first time in years, he has allowed a journalist to sit in on a day's shoot. If I play it carefully, he might actually speak to me, too.

He has leased a beach house full of windows and sunlight. His favourite cook, John, is busying himself over the gas rings. 'I hope you're hungry,' he says. 'I'm doing a big lunch.'

He has prepared garlic bread, asparagus, green salad, legs of chicken, a steaming, glistening mountain of tomato fusilli, and chocolate brownies, to be washed down with Diet Coke and spring water. Herb's entourage is all there: three assistants, a stylist and her assistant, a location manager and her assistant, a make-up artist, a hair stylist, one model, two bodybuilders, the bodybuilders' gym manager, and two or three hangers-on who do a bit of this and that. 'Herb's keeping the numbers down today,' someone says to me. 'He wants to keep it low-key.' I nod knowingly.

A slight man in blue cord shorts, grey T-shirt and deck shoes wanders up. 'Hi,' he says, with a half-smile. 'I'm Herb.'

Today he is shooting an advertising campaign for Sol, the Mexican beer that is a hit in Britain because it is light and cool and people like the idea of sticking a slice of lime on top. These days, fashion sells anything. Supermodels sell cars, so why can't superphotographers sell beer?

Two bigwigs from the Sol marketing team have flown over to watch. They are paying Ritts around dollars 140,000 ( pounds 93,000) for a day's work, but they look starstruck in his presence, as if he is the one doing them the favour. I am wondering how come it is already lunchtime and Ritts has not yet lifted a finger. 'Herb likes to shoot late,' explains an assistant. 'It's the light, you see. Late afternoon light is the best.'

The Sol people want Ritts to make their beer hip again. In Britain, we drank 31 million bottles of it last year, but the importers are worried that the brand has peaked. 'We've got to remind people that we're quality, we're not a fad,' says Sol's Jose Arellano, his forehead glistening in the sun.

Ritts's brief is to make Sol seem something wild, young and fun. How he does it is up to him. He has picked a top Israeli model-actress, Michaela Bercu, a 6ft Amazon with a dazzling smile. She has flown in from New York for the day to do the shoot. 'Saw you in Dracula,' Ritts says to her. 'You had the fangs on, right?'

Her fellow models for the day are two short, squat bodybuilders, who stand to one side looking like penguins, faces impassive. Herb briefs them: 'These are just image pics. We'll move it around, see what happens. It's not a competition. Don't worry. Eat whatever you want.'

Lee Priest, three times 'Mr Australia', piles his plate high with chicken and eats slowly, brow furrowed in concentration. Lee came to Los Angeles just the week before to turn professional. He has never heard of Herb Ritts but, what the heck, he's being paid. While he eats, he looks at one of Herb's books, full of homo-erotic pictures of two naked male bodybuilders rubbing their bodies against each other in the surf. He looks confused.

He need not have worried. Today's shoot is good, clean, family entertainment. Ritts leads the way on to the beach and within minutes the model and the two bodybuilders are running along the sand, waving bottles of Sol, laughing into the camera. Ritts works quickly while his three assistants scurry around him, reloading film, shouting out light readings, changing cameras. Soon everyone is deep in the water and the bodybuilders are holding Michaela high in the air.

Only the hair stylist does not look happy; she is ice-queen white, shielded from the sun by an ankle- length long-sleeved dress and a big floppy hat. As an extra precaution, she carries a parasol. She talks about melanoma to anyone who will listen and offers her factor 48 sunblock.

We break at four. Ritts is disappointing me. No prima donna tantrums. It is clear that he is the boss, but he does not shout at anyone. The San Francisco Chronicle once called him 'the nicest control freak in LA'.

'He's great to work with,' says Michaela. 'He doesn't push people around. You feel you're all working together as a team.' She sweeps back her long golden hair. 'And, of course, he always makes me look beautiful.'

Ritts comes in. He is delighted with the work so far. 'It was fun. They were great sports,' he says. 'Lee looked great.'

Suddenly I realise he is giving me an interview. 'I love shooting outside in California - I love the beach, the desert, the light. It's my outside studio. There's this feeling of freedom, of the elements. It lends itself to edgier pictures.'

Over the past few years, in addition to his fashion work, he has photographed celebrities for Vanity Fair, Rolling Stone and American Vogue. So I ask him how he can advance from here. 'Well, it's a question of finding people who aren't your typical celebrity. I did Gorbachev and Stephen Hawking. It's good to branch out and do different things. But it doesn't get boring doing the same people. They change, I change. I did Madonna again three weeks ago, and it was different from the previous time.'

The best of his portraits were published last year in his book, Notorious. He is well known for his ability to persuade difficult celebrities to do the things he wants. Prince, for example, refused to be photographed in motion. 'You have to pay me dollars 90,000 in order to have me move,' he said. Ritts countered: 'Well, I don't have dollars 90,000. This is an editorial photograph for Vogue. I need some action on this page.' He got it.

Another time, he got Sylvester Stallone to kiss Brigitte Nielsen in front of fans at a beach club. 'I wanted it playful. I wanted him to dip her over the edge of a rooftop overlooking the pool. He didn't want to shoot outside. I whined and whined and whined until he said yes.'

Back on the beach, he again works very swiftly. 'Close your eyes. Hold. One, two, three. Lee, do your teeth like it hurts. Smile. Hold on to her waist. That's good. Great]'

On the face of it, one fashion photographer works much like another. The magic is in the framing of the picture. Ritts knows better than any other photographer how to intertwine bodies, water, sand and light. As the sun goes down he switches into an even faster gear, urging on the bodybuilders who are feeling the cold.

It is 7.30pm and the sun goes under. It is done. Ritts is pleased. Everyone's pleased. 'If that won't sell beer, nothing will,' says an assistant.

Jose Arellano is beaming with delight. 'Incredible,' he says. 'Incredible. I thought, you know, he would use 10 films or something like that in two hours. But he has been working all afternoon. He has taken hundreds of pictures.' Mr Arellano seems to think he has got his money's worth. I walk back along the beach with Ritts. 'It was fun,' he says. 'The guys were great sports.'

We talk about the other advertising work he has been doing or has got lined up: for Lancome, Faberge, Levi. 'I like to mix it up each week, this and print work. That's the way I like it. I'm always competing against myself.'

He turns round to look at the view. Sun, sea and blue, blue sky stretching away to the horizon. This is his territory, California at its golden best. 'It's good out here, relaxed, perfect.'

I have to agree. Right at this moment, on Zuma beach, I am thinking of emigrating.

Herb Ritts's advertising campaign for Sol will be launched in the autumn.

(Photograph omitted)