PERRY OGDEN is now in his mid-40s. A distinguished fashion photographer, long resident in Ireland, he took his career in new directions in the 1990s with a series of photographs, later published as a book, depicting inner-city youths and their horses. Now he has followed up that endeavour with a hugely impressive film named Pavee Lackeen.

Stirring up memories of Ken Loach's Cathy Come Home and Iranian cinema of childhood, the unforgiving, naturalistic picture follows a few days in the life of a young Traveller and her family.

It's a notable roster of work. But, as Ogden admits with a smile, when interviewers scrutinise his CV one thing still jumps out: he went to Eton.

"We weren't very posh at all," he laughs, managing to avoid sounding too defensive. "My mother was the editor of the women's page on the Times. She was in favour of state education and my father was in favour of private education. At first she won out." And, indeed, he doesn't sound all that snooty (certainly less so than this month's most prominent old Etonian, David Cameron, who, by my calculation, would have been a new bug when Perry was doing his A-Levels). Balding hair shaved to stubble, clothes selected to look thrown together, he comes across - the odd strangled vowel aside - as agreeably classless.

Raised first in Shropshire, Ogden, whose father was an army officer, traces his enthusiasm for the media back to his days at the City of London School.

"That was next door to the Times. I used to play football, then go and hang out in the office. I'd be taken to the printers and watch them set type. Ever since I have always loved the smell of newsprint. I think that smell was where I got my taste for the smell of the darkroom. Afterwards I would get a cheese roll in the canteen. Then after she died I was sent away to school." The last phrase is delivered coolly, not with any mournful regret.

But the death of his mother, when he was just 11, remains a significant event in the Perry Ogden story. At Eton he co-edited a terrifyingly unfrivolous school magazine - interviews with David Bailey and Andy Warhol, rather than profiles of the janitor's cat - and then, after leaving school, spent some time assisting a former colleague of the photographer Lord Snowden. By the mid-1980s he was receiving commissions from The Face, Harpers and Queen and the Sunday Times.

"It's hard work being a fashion photographer," he says. "When I started out I was interested in just taking photographs of people and I then got sucked into fashion. It is much easier to make a living with that than taking portraits or doing reportage. As I became more exposed I started up on my own. That was in 1982. Then I went to New York for three years. I was always supremely ambitious. I wanted to succeed. In a sense there was a gap within myself that was the loss of my mother. And this identity I was creating was going to fill that gap."

Ogden first came to Ireland in 1983 to shoot a commercial for a Japanese fashion company. His mother's family were Irish, but she had never got round to bringing him here before her death. He loved the country and returned for shoots as often as possible.

"Then I met a girl here, fell in love, had a child, fell out of love. The usual story," he says. "I have always loved photographing in Ireland. It is such a different place to England - less tame. Though things have changed a lot, of course."

Ogden eventually decided to commit himself to Ireland and set up a studio in Dublin's Capel Street. He still lives above the shop. In 1994 he found himself at the horse fair at nearby Smithfield Market, where the youths and their mounts transfixed him. Pony Kids, first an exhibition, then a book, followed.

Was the enterprise a conscious attempt to do something that mattered after the magnificent frivolity of fashion photography?

"I had always had other projects going on," he says. "But fashion was what was being published. I still do it and it helped me make this film. But it is not enough for me. I want more. I don't mean that in the sense of being ambitious. I just want a fuller experience in my work."

Pony Kids was a significant success. The book was reviewed all over the world and "surprisingly, given what it is" Ogden even managed to sell the screen rights. His initial plan was to use any money he received for the finished film, to finance an independent project, but Pony Kids: The Movie still remains in development. Nonetheless, he persevered and eventually managed to get Pavee Lackeen together.

At the film's heart is a fine central performance by young Winnie Maughan, whose family lives in a caravan parked on an unlovely stretch of road near Ringsend in Dublin. Ogden first met Winnie, now 11, via her brother. Perry and his co-writer, Mark Venner, saw the young lad put in a splendid performance before the judge at the Children's Court. Perry introduced himself, passed around a few copies of Pony Kids as evidence of his bona fides, and was taken back to meet Winnie and the family.

"She did this amazing spiel. She was so eager to impress. It was obvious she had this quite amazing imagination." The film - loosely plotted in the classic cinema vérité style - follows the family as they try to avoid having their caravan moved to an even more poorly appointed site. They meet with a Travellers' support worker to discuss their rights. Winnie visits the doctor. She gets dressed up and has some chips. In one particularly amusing scene, she is called upon to sing and, rather than dragging up some mournful ballad, delivers a juicy rap number.

Though we do see Winnie and her pal sniffing petrol, the picture is unapologetically on the Travellers' side. Ogden was keen to listen to the family's concerns about how they were to be depicted.

"They didn't want anyone to be filmed begging," he says. "They had pride. Once or twice we would ask them to do something and they would say no. But we developed a real level of trust with them."

So has Pavee Lackeen helped Ogden develop that "fuller experience" he was seeking from his work?

"I guess I almost feel a responsibility to tell these sort of stories as we live in this luxurious age of celebrity, all of which is pretty meaningless." A fashion photographer speaks? "Yes. I suppose a part of my life was involved with propagating that. I am to blame, so I am riddled with guilt." He laughs drily as he speaks.

Pavee Lackeen is released on November 11th