I'm trying to learn how camera lenses work, and have gotten stuck. Say that we have an optical system consisting of a single lens with focal length f, and we want to take pictures of objects which are infinitely far away. The light rays will in other words be parallel, and when these rays pass through the lens they will be focused at a single point at a distance f away from the lens. But, how can we then take pictures of such objects if all of their rays are focused at a single point?
I'm not questioning the laws of optics since obviously they work, but I can't figure out where the error in my thinking is. Could someone please shed some light on this (pun intended)?
EDIT: For those who are interested, this question is closely related (although not exactly the same).