As thousands log on to view the latest snaps taken by a new breed of fashion photographer, street style has taken over from the celebrity-driven catwalk as the setter of trends

London Fashion Week and who, exactly, is looking at whom? Inside a venue in Covent Garden, an audience of newspaper fashion writers, glossy magazine stylists and department store buyers are watching a new generation of designers at the Fashion Fringe show, on the lookout for next season’s big trends.

Meanwhile, in the street outside, Yvan Rodic is aiming his small digital Canon camera at a 19-year-old woman with a pudding bowl haircut and very large Ray-Bans.

Tomorrow, it is likely that many of those same fashion industry professionals inside will be analysing what young Scarlett Tull was wearing outside, and making a note of the way her scarf is tied and her funny little tapestry shoes.

Rodic, better known by his online moniker, Facehunter, is doing his daily trawl for experimentally dressed, off-beat twentysomethings, whom he photographs here and now on the street, uploading the results the next morning for a daily international audience of around 30,000.

In a shrunken red jacket, black bow-tie and glittery ankle-length jeans, the Swiss-born 31-year-old, based in London, looks like just the sort of quirky young thing he’d like to snap himself.

Lily Atwood, 19, from Brighton, looks on as her friend Tull poses for Radic. "I’m a huge fan of his," says the art student who wants to work in the fashion industry. "I look at the site twice a day. Loads of my friends have been on it - it’s a real coup."

Why has it got such appeal and credibility? "Because Yvan has a really good eye and the people he photographs are amazing," sighs Laurel Harple, an 18-year-old Central St Martin student also aiming to work in fashion.

The Facehunter, along with The Sartorialist based in New York, is one of a growing number of street-fashion photography blogs. Celebrating individuality, focusing on style rather than designer labels, and saluting the fashion savoir-faire of the unknown passer-by, when it first appeared on the internet in 2006 it provided a welcome counterpoint to the mass-media’s fixation with celebrity style, which has monopolised fashion coverage for the best part of this decade.

"It’s a look," says Rodic, of what attracts him to photograph a certain person. "There’s something special, fresh, not déjà vu. Sometimes someone is wearing amazing shoes but the rest of the look doesn’t work. I photograph people, not clothes."

These blogs are now required daily reading for both those in the industry - including top designers such as Paul Smith and Net-a-Porter founder, Natalie Massenet - as well as non-professional fashion fans.

In 2007, Time magazine nominated Scott Schuman, the eye behind The Sartorialist, which attracts 70,000 hits a day, as one of the most influential figures in design, while an exhibition late last year at Colette, the high-end Parisian boutique, paid homage to the best fashion photography blogs in the first exhibition of its kind.

It seems that street style today matters more than ever.

"In the past few years there’s been a surge of interest in fashion from the mass media on TV [Sex and the City, Ugly Betty] and in movies like The Devil Wears Prada," says Sarah Bailey, deputy editor of Harper’s Bazaar. "But, at the same time, we’ve witnessed the advent of the citizen fashion editor, aka the style blogger. And it is this latter phenomenon that is keeping fashion on its toes."

The influence of Facehunter is readily acknowledged by big brands such as Topshop. "Those sites are so important to us, more important than the catwalk, actually, because they’re about how real girls put themselves together - as opposed to male designers deciding what women should look like," says Andrew Leahy, head of press for Topshop.

Rachael Proud, 32, senior buyer for the store’s directional Boutique, Unique and Designer ranges, indicates just how useful a site like Facehunter can be to a time-pressed high street designer.