Katie Waggett's best photograph: Sunday worship with Joy

‘Joy was dancing in church with her children in London. She was in her element – her dress speaks to her sense of cultural pride’Her name is Joy and I photographed her outside one of the many African churches in south-east London. I had just finished photographing a mosque on the same bland industrial estate when I found the blue wall, then spotted Joy dancing in the church with her children. I thought: “That’s a portrait I’ve got to get,” and asked if s