It's more about subtracting every single buck from the tourists that still flock there. Gentrification and the need for developers to maximize their profits from every square inch of the place means that there just aren't any scruffy little basement clubs left. Those scruffy little basement clubs were the areas lifeblood. Now, it's all penthouse flats and global brands. They destroyed the very thing that drew people there in the first place - it's superficial sleaziness.

The reason why so many of my photographs in the book were taken in stairwells and corridors was that that was the only bit of spare space available and, in some cases, the only place where there was enough light to see anything. Even then, it was often so dark that I couldn't tell which gender my subject was (not that I particularly cared) and too dark, before the era of autofocus, to focus. I had to find a light (or carry a torch) and pre-focus.

When I gave up my office job and became a full-time professional photographer, my fortunes certainly improved markedly. We moved away from the council estate into our own house and for the first time in my life, I had a little spare money.

When I was starting, I was very much influenced by the straight up, eyes to camera style of August Sander. He is really the only one. Had I known then the work of people like Ken Russell, Vivian Maier, Helen Levitt, and Steven Berkoff, they would undoubtedly have influenced me too.

Many nightclubs from this era were very loud and very dark. Plus some of the best ones were incredibly crowded. To begin with, I could seldom get back far enough to get people into frame from head to foot and when I could, people would be constantly walking in front of me all the time. Then I bought a 24-mm lens and only had to be four or five feet away.

I preferred that option, where my camera (and by proxy, me) could look them straight in the eye. The way they reacted to me was always interesting. Sometimes hard young men would reveal vulnerability and a softer side. In the case of teenage girls, I often got a fascinating glimpse of the woman inside.

Once I became a photographer, it stopped me being scared or intimidated by gangs of young men of whatever stripe. Initially, I could hide behind my camera but eventually I came to realize that if I was polite and friendly to them, then they probably would be to me too - a good life lesson.