The photographer's studio

An original fiction passage set in the nineteenth century.

Miriam led the visitor to the chair beneath the studio's high window. He sat stiffly, one gloved hand resting on his knee, while she disappeared beneath the black cloth behind the camera. Emerging again, Miriam moved the chair towards the light. She then straightened the visitor's collar and asked him to keep still. At last, she returned to the camera and uncovered the lens.

Give two details about Miriam's preparations for taking the visitor's photograph.