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.

In the age of social media, you have the selfie and some people - not always young people - seem obsessed with showing the world what their face looks like almost every day. Just like some people are obsessed with showing the world what their dinner looks like. It's beyond my understanding to be honest.

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.

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.

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.

The big downside to the global village that the Internet has created is that nothing has time to grow out of the public gaze and, even more dangerous, whatever your personal interests might be, there will always be someone somewhere to provide validation and encouragement.

I started out, in the mid-'70s, taking photographs of rock bands that I liked but not because I really wanted to photograph them. Initially, I was pretending to be a photographer, simply so that I could go up to the front of the crowd and be a bit closer to the bands. But, I found I was gradually developing an interest in the photos I took.