Quote Originally Posted by Ole
Quote Originally Posted by Ed Sukach
BTW .. "diffraction kills sharpness" - is true - but without it, "pinhole" would not work at all.
To the contrary, Ed: Without diffraction, pinholes would give perfect images!
*MOST* interesting. If not by diffraction, how does a "pinhole" cause an image to be formed on a plane?

If we increase the size of the pinhole, we will decrease diffraction. There must be some limit ot the increase. Where?