A single spectacular image has its satisfactions. It is a self-contained thing, and part of its force comes from that ­self-containedness. It functions like a haiku. It is an image in a hurry, though it disguises that hurry somewhat.

Something else happens with images intended for a series. These images are like individual sentences in an essay. The essay as a whole is obviously what matters, and spectacular individual sentences can go against the grain of the whole essay, unbalancing its intention. The images destined to be part of a book might embed tensions between each other more complex than what is feasible even in an essay.