Sarah Moon French, b. 1941

A woman in a Chanel evening dress, and the picture has already let her head go. It tilts up and out of the top of the frame, smeared into the exposure, gone. What stays is the dress: a sequinned bodice on two thin straps, catching the light in hard little points, and below it a dark skirt that swells and blurs as though she had just turned on the spot. Her right arm hangs straight down at the edge of the frame. The hand at the end of it is open, and still.

The arm is the part nobody styled. Everything above it has been arranged and then dissolved on purpose. The arm simply hangs, the way an arm hangs when the person it belongs to is tired and waiting to be told she can go. Fashion photographs are usually careful to keep the model inside the clothes. This one lets her leak out at a corner, through a wrist.

Sarah Moon spent years in front of a camera before she ever stood behind one, and she photographs models like someone who remembers the hours. The face has been given away, so there is nobody to recognise and no beauty to rate. There is a body doing a job in an expensive dress, and one open hand that has stopped performing. The amber of the print and the chemical bruising round its edges make the whole thing look recovered rather than taken. It is a picture about the end of a very long day.