Sinclair began photographing British artists in 1991 when the art historian David Mellor commissioned him to make a series to accompany an exhibition he was curating at the Barbican Art Gallery on artists who came to prominence in the 1960s. Meeting by chance on a train journey, Mellor had asked Sinclair to name the British artist he would most like to photograph and he replied that it was John Piper, partly because he has always loved the artist's work but also because he thought his unusual, slightly elongated face and deep-set eyes would make a great portrait. Mellor put them both in touch and the resulting image became the first in the series.

Sinclair had started portrait photography a decade earlier when, having trained as a painter at Newcastle University, he joined a Moroccan circus as a drummer and started capturing his fellow circus acts. After six months Sinclair left the circus and then in 1985 he bought a Hasselblad camera, which he found was the ideal tool for making portraits. Since then Sinclair has captured over 80 artists and the square format has become a defining feature of his work.

Location is crucial to Sinclair's compositions, he always looks for a background that works visually before he begins to think about the person he is going to photograph. He also includes references to their work, working methods or materials so that each portrait is informative on different levels. Key examples in the exhibition include Sinclair's portrait of Celia Paul in her beautiful, slightly austere studio with distressed floor boards and a mirror which perfectly complements her serene presence; and Sir Anthony Caro in his north London studio, set against a white wall with iron hoops suspended from a bracket.

The majority of Sinclair's portraits are in black and white, a decision which owes a debt to Hans Namuth's portraits of the American painters of the 1940s and 50s such as Jackson Pollock and Franz Kline. It also reflects his preference for the sense of austerity black and white evokes and the way it handles skin tones. However the exhibition also includes some of Sinclair's colour works of Anthony Caro, Fiona Rae, Albert Irvin, John Hoyland and Gillian Wearing which have never been seen before, not even by the artists themselves - rediscovered by Sinclair when the Guggenheim Foundation requested his portrait of Caro for their Venice collection.

Describing what he is looking for in his portraits, Nicholas Sinclair says: "For me there needs to be a connection with the subject if the picture is to have any lasting value. It's the same with characters in the cinema, in the theatre and in literature. If there isn't a connection, however subtle, you simply lose the viewer's attention, so I'm looking for that moment when, either consciously or unconsciously, the sitter reveals something about themselves that the viewer recognises and can relate to."

About the artist

Nicholas Sinclair was born in London. His work has been widely exhibited and published in Britain, Europe and the USA. since 1983. He was made a Hasselblad Master in 2003. www.nicholassinclair.com