Quote Originally Posted by momus View Post
Even considering that an enlarger is blowing up a small negative many, many times, wouldn't the same sort of DOF apply? Not a direct correlation of course, but when in doubt stop it down as long as you don't have real long exposures?
Bear in mind that an enlarger is really a macro camera with the negative as the subject and the paper taking the place of the film receiving a larger than life size image.

The most critical relationship is between the lens and the negative.