I took this in 1969, during the filming of A Clockwork Orange. I think it was on location in Kingston, London, but I can't remember exactly what was being shot that day. The structure you can see is a camera platform, and we were sheltering from the rain underneath it. I was chatting with Stanley Kubrick, and I thought to myself: there's a picture here.

I waited until Stanley paused, and put his hand up to stroke his hair back from his eyes – then I just took it. I didn't have to set the focus as I had a wide-angle lens; I knew, so long as I had the right exposure, the depth of field was enough. The camera he's holding is his Arriflex. It was for handheld work: lightweight, and stripped down to the camera body and lens.

The minute after I got the shot, there was a creaking and straining, and the platform collapsed. Stanley never normally rushed and was the calmest of men, but he was out of there like a bolting rabbit. I'd never seen anything so quick.

This was the third of Kubrick's films I worked on: I'd also been on set for Dr Strangelove and 2001: A Space Odyssey. I was what they call a "special", brought in for 30 or 40 days for a specific purpose. I was taking pictures of the crew because Stanley had an idea he would use them for the title sequence, but he didn't in the end. He never gave me any particular instructions; he once told me that he asked me to work for him because I "stood in the right place".

Before the days of digital, you had to rely on the feeling you had when you took a picture that it would be all right. I like this one very much. It's unusual to have someone's feet so prominent, but it doesn't take away from his expression. He was the least lazy of men, but there's something very relaxed about the pose.

CV

Born: Kemsing, Kent, 1932.

Studied: "I learned a huge amount from a photographer called Michael Wallace."

Influences: "Late 19th-century people, such as August Sander.".

High point: "It may be now. I am working on a series of photographs of Brooklyn."

Top tip: "Follow what you love. Otherwise you'll be disappointed."