In the late 1980s I was working at Sub Pop records in Seattle as a jack of all trades, and also doing in-house photography. One evening I went to see the label’s new signings, Nirvana, but I just didn’t get it. I didn’t even photograph them that night, as I wasn’t impressed. But that all changed very quickly. I heard their debut album, Bleach, and was blown away. And the next time I saw them I was like, “Oh my God, this is not the same band.” Kurt Cobain was doing Pete Townshend jumps and it was a crazy show. I photographed the band for years after that, taking thousands of pictures. They knew my work before I knew them as a band, so I think they trusted me from the get-go. It was the same with the other grunge bands I photographed – I was just another local dude, I wasn’t parachuting in from New York or London.

Seattle had a reputation for wild audiences. We were enthusiastic and physical without being violent. It seemed natural to me to include the audience in my photos, because it’s all part of that cathartic interaction between musicians and their fans.

Despite being a so-called “people photographer”, I’m somewhat of an introvert. But so was Kurt. We both opened up when on stage: that was the place where you could express yourself and where everything else dropped away. That’s how I felt up there with a camera. The way I work is very loose and fluid, and I liked to get involved, so I was often dancing at the same time that I was photographing. That was something that bands liked too.

This shot was taken at a Nirvana show in Washington in 1990 and it was a chaotic one. There were lots of stage divers and roiling bodies. I was standing over by the PA at stage left when this guy next to me suddenly scrambled to the top of the amplifier. He’s up there, knees bent, doing a dance, taunting the crowd. I tugged on his pant leg and was like, “Dude, don’t do it!” I thought he was going to break his neck. But he wasn’t going to pay attention to me, so then I thought I’d better set up for the shot. I had my Nikon FE2 with a 24mm lens, and at the time I always used an off-camera flash connected to a cable. So I focused out on to the air where I thought he might be and held the flash up over my head. Two seconds later he launched himself and I got just the one shot. He wasn’t hedging it either. He really leaped. Miraculously, he was caught by the audience.

It’s become an iconic photograph – I don’t need to be humble about that. It represents an era, not just in music but in the culture. Everyone is completely lost in the music in their own sort of way. I have two very close friends who are a long-term couple who are each in the photo, only yards away from each other but two years before they met. I think that’s amazing.

This photo represents a sweet period for me. I wasn’t beholden to anyone when taking these photographs. Most assignments at the time were just boring posed pictures, so I went out and did the live stuff because I knew that would be my art, and what I thought would stand the test of time. It was a really creative period because the bands weren’t beholden to anything either – yet. It was a period in which we could experiment together.

Photographing Nirvana from so early on, I saw Kurt when he was just the wallflower in the corner, and watched him become this rock god-like figure. It was kind of absurd, and obviously it all happened much too fast. But my photographs aren’t about the band or Cobain, they are about the music. I wanted them to really embody its spirit. Photos like this go back to why Nirvana were so important in the first place: the music and their performance of it.

Charles Peterson’s CV

Born: Longview, Washington, 1964.
Trained: BFA, University of Washington
Influences: “Garry Winogrand, Larry Fink, Werner Bischof”
High point: “Sitting next to the legendary Jim Marshall on a panel of rock photographers”
Low point: “Whenever I’m asked for yet another memorial photo”
Top tip: “Bend your knees, think fast, look behind you, and stay loose”

• The photobook Charles Peterson’s Nirvana is published by Minor Matters