.
Bruce Chatwin described Mapplethorpe's nudes as "cold and sharp".
Only a certain sort of image arises from such circumstances.
The Paris police declared they were "so obscene that even to pronounce the titles would be to commit an indecency".
Meanwhile, Nobuyshi Araki takes erotic pictures which play with ambiguities and make clever visual puns.
But there's a difference of intention too.
The respectable pioneers of French photography, Auguste Belloc and Felix-Jacques Moulin for example, ran lucrative occult trades in pornography.
One involves coercion and disgrace, the other beauty and delight.