It’s a Saturday morning and Westbourne Grove Church in Portobello has a buzz like that of a school assembly hall before the teacher walks in. Chattering in groups, rocking in their chairs to a selection of rock, soul and funk music, 272 people – including me and my teammate – wait for their Shoot Experience to begin.

Begun in 2005 by a 31-year-old web designer, Brett Jefferson Stott, the Experience hauls Everyman out of his weekend seat in the pub and sends him on a photography adventure that could lead to a gallery exhibit. Last year it had a sell-out success with Shoot London, hosted at Tate Modern and exhibited at City Hall, and it is preparing to repeat the Experience this month.

We clutched our own digital cameras, from the simplest to the most sophisticated, as Jefferson Stott explained what was in store. This was Shoot Portobello, and from noon, teams were to roam the area solving ten clues, today on a music theme, and documenting the answer with a photograph. Memory cards were to be handed in by 5pm containing a photo for each clue for a slide show and awards ceremony in the evening.

If I’m honest, after hearing Jefferson Stott describe the Experience as “a chance for anyone with creative talent to get some credit”, we – both self-proclaimed “arty types” – secretly expected to excel. We were soon scuppered.

First, not being locals, we found solving the clues hard. “RIP Jimi, your experience ended here.” We noticed other teams tapping away on laptops using the free wi-fi connection in the refurbished church, while we only had a dodgy Wap mobile. We headed to an internet café but, not having thought to bring a map, we took a while to find it.

When it happened, solving a clue was so thrilling that our girlish giggles were momentarily replaced with a worrying desire to crush our opponents. Tearing up the street to 22 Lansdowne Crescent, formerly the Samarkand Hotel, where Jimi Hendrix died, we found another team already there, one lying on the pavement sporting an afro wig while a teammate photographed her. Stifling pangs of competitive bitchery, we tried desperately to think of our own dynamic solution, but had to settle for a shot of the outside of the hotel with a broken-down car outside. Must do better.

Between chatting with pub locals for hints and dodging market stalls, we did do slightly better, taking one photo that we were really proud of – a nice portrait of a street band – and at least answered all the clues. Well, except one – we ran out of time so we photographed a wall on our way back.

Jefferson Stott puts Shoot Portobello as one of his favourites so far – he has hosted others in Brixton, Shoreditch, the City, and East and West London. “The original concept was aimed at photographers,” he tells me. “But we quickly realised that it’s ordinary people who are up for something fresh and exciting, and the digital explosion has made this possible.”

Shoot Experience’s research indicates that its demographic is largely professionals aged 21 to 45, and demand is such that this year’s Shoot London has already sold out, so a “lite” event has been opened in which clues are e-mailed, photos uploaded and winners announced online.

Shoot Experience is also preparing for the launch of Shoot Nations in June, an international competition for young photographers to be showcased at the United Nations, and Experiences are planned in Liverpool, Bath, Berlin, Barcelona, Milan, Toronto and New York City. Though the concept seems novel, it is not alone in offering such adventures – Photomarathon UK is another company now hosting similar events in Cardiff and Glasgow.

Back at the church a line of helpers with laptops busily processed our memory cards, and beer and music filled the gap before the slide show. But when it started, we were slightly disappointed to see that our masterpieces were just like everyone else’s. “On the whole the standard is unbelievably good, but I don’t think we educated people enough on what we expected this time – people felt they always had to go to the answer rather than portray it in other ways, so there was some repetition,” Jefferson Stott admitted afterwards.

Prizes for photos ranged from vouchers to cameras, but the focus is not on technical brilliance, he explained. “We look for photos with a personality and photos that capture the spirit of the day.” Resigned to not winning any prizes, we were comforted later to find that one of our photos was chosen for the event exhibition in Gail’s Bakery on Portobello Road.

It is rare that a Saturday has been mentally stimulating and physically exhausting enough to leave me ready for bed at 8pm. Our photos are not award-winning, but the excitement of scrambling up the street to photograph the hotel where Alice Cooper kept his snake is one that you probably won’t have felt since school, and it’s overdue.

— Shoot London is on May 19 (sold out) and Shoot London Lite is on May 20. Book tickets online at www.shootexperience.com . www.photomarathon.co.uk organises similar events in Glasgow and Cardiff

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