Shooting at York Minster is always a pleasure, but working there at Christmas is something very special. The various services present unique challenges – huge congregations, the cold, and some very dark scenarios which test any photographer. My role is to see but not be seen – to capture everything, but not get in the way. I do this by liaising closely with the Clergy and vergers before any service, so I know exactly where everyone* will be and when, so I can position myself