An 106 millimeter focal length lens is used to focus an image on the sensor of a camera. The maximum distance allowed between the lens and the sensor plane is 139 millimeter.
a) Determine how far in front of the sensor should the lens (assumed thin) be if the object to be photographed is 3.0 meter away from the lens?
b) Determine how far in front of the sensor should the lens (assumed thin) be if the object to be photographed is 1.0 meter away from the lens?
c) Find the closest object this lens could photograph sharply?