I was 1 of 2 photographers backstage at Live Aid - here's what happened in the VIP area

Live Aid was the concert that changed the world and the show by which every mega-gig is still compared. Forty years ago tomorrow, showbusiness still hasn't seen anything like the stellar line-up of stars which gathered at Wembley Stadium and, in Philadelphia, the John F Kennedy Stadium on July 13, 1985.

Yet, despite the genuinely once in a lifetime array of talents who performed at Live Aid, backstage at Wembley was an intimate affair. There were actually two areas where performers could chill out on the day. The main backstage was at Wembley Arena, 100 yards away.

The more intimate, exclusive party zone was reserved for the day's top-tier talent, at a gazebo just behind the stadium's stage. It's where Freddie Mercury held court before and after Queen's monumental Live Aid performance.

Paul McCartney, David Bowie, Elton John, Sting and George Michael were among the handful of other performers who hung out with Freddie on the day.

And just two photographers were there to capture the mood: legendary portrait star David Bailey and Denis O'Regan, a seasoned rock lensman who had been official photographer for Bowie, The Rolling Stones and Thin Lizzy.

O'Regan was responsible for organising the official Live Aid photo book documenting Wembley, having persuaded Bob Geldof it could capture the intimate moments backstage on the day. O'Regan did so at just two weeks' notice.

"Live Aid was so complicated to pull off, contracts to organise a film or an album of the shows would have been too protracted to arrange on top of the concerts," he explains. "But I didn't see why there couldn't be a book. I phoned Geldof, who said, 'If you want to do a book, you f***ing do it, then'."

Sadly, O'Regan's book ended on a sour note. He sent all the negatives of his rolls of film to the Band Aid office. When he asked for them back once the book had been published, he was told by Band Aid they'd been thrown away!

"That's upsetting," O'Regan, 71, says today with remarkable understatement.

The photographer, who went on to work with Queen, Pink Floyd, The Who, The Bee Gees, Duran Duran and AC/DC, continues: "A lot of music history has been lost. Just before the encore, Pete Townshend and Paul McCartney hoisted Geldof onto their shoulders. I was stood directly behind them and took a photo, but that one was chucked out."

Because Live Aid's inner sanctum was so exclusive, O'Regan saw the cream of the music industry on their best behaviour. He recalls: "It was a very relaxed, secure environment in there. You had star upon star.

"Once you had Freddie, Elton, Macca, Bowie and George Michael milling about, there was an unspoken agreement of: 'We'll give all of that ego stuff up for today.'"

Fortunately, O'Regan kept a few precious negatives of the concert that changed history. Here, he talks us through the highlights.

FREDDIE AND BOWIE CLOSE-UP:

When they were in conversation that day, Freddie and David were like two fag-ash Lils, smoking and having a catch-up. They didn't meet up that much, but they were able to have a casual chitchat. I'd have eavesdropped on their conversation if I'd known it was going to be something special in music history, but I didn't bother, I was too busy taking pictures.

CROWD:

The crowd being sprayed with hoses was one of the things I remember most about that day. It was just so hot. The heat helped make it a national event, as it meant everyone at home was having barbecues and bringing the telly out into the garden. In the stadium, you were out there in the sun all day, so those hoses were needed.

I'm not sure the crowd knew how amazing Live Aid was going to be. When they bought tickets, they didn't know who was going to be on. It's one reason why Queen were so amazing. Nobody knew they'd be playing that day, but they turned that Wembley crowd into a total Queen audience. That impressed the world.

BACKSTAGE CLOCKS:

Not only was Live Aid so ambitious, it was broadcast live on TV, so you just couldn't make a mess of it. But the day felt very 'seat of the pants' as there was no precedent for a show like it. But it seemed to work so well. There was no kerfuffle of: 'Where has so and so gone?' Those two clocks, along with that relentless list of artists next to them, summarises the whole day. The quote underneath, 'Kill time and you murder success', was originally from the punk label, Stiff Records. They had a few good catchphrases like that, and someone at Live Aid had borrowed it.

FREDDIE AND ADAM ANT:

This picture of Freddie holding court, while Adam Ant is sat next to him like Billy No Mates, says a lot. I don't think Freddie and Adam spoke at all. Freddie and Roger Taylor took that table over completely. Adam was a great theatrical performer, like Freddie, yet never the twain met. Elsewhere, George and Elton were chatting in the small Hard Rock Café backstage. Sting mooched around a lot too.

DENIS O'REGAN WITH DAVID BOWIE:

David was the first singer I ever photographed. When I was 19, he was recording at Olympic Studios in Barnes, west London, which was opposite a newsagent where I had a Saturday job. I took a photo of David with two teenage fans and he joked I should become a paparazzi. The year before Live Aid, I did a book on David's Serious Moonlight stadium tour, the first time he'd let people see what he was really like on tour away from the shows.

David's pose here is typical of how goofy he could be. He was always laughing and telling stories, doing impressions of fellow diners whenever we went out to eat. David wasn't what I expected at all, he was so down to earth. He loved sushi, but he'd eat any old crap that was around. Before he gave up alcohol, he was a fag and a bottle of beer guy. This photo is typical of David with me. I also have one where we're stood back to back, pretending to not know each other.

FREDDIE AND DAVID BAILEY:

I didn't know David at all, and I'm not sure if he'd ever met Freddie before either, though they were happy to pose for my photo. While I was wandering around, David had a studio set up backstage, where he'd wheel people in and out.

BACKSTAGE PASSES:

The backstage area wasn't at all like how it was portrayed in Queen's Bohemian Rhapsody film, as it was very chilled. There was a giant fence outside, so no-one could get through. A lot of fans stood there. But, as you can see here, there were very few backstage passes. I had one Access All Areas pass, and another Crew one, so I could go anywhere. As there were so many bands, there was no mode of access if you weren't working. Apart from Queen's entourage, I don't think there were any hangers-on that day. If you weren't working, you weren't in that backstage area, simple as that. The show couldn't have run so well if it wasn't like that. I kept those two passes as my little piece of history.

Denis O'Regan's book, David Bowie (ACC Art Books, £60) out July 22