Quote Originally Posted by jasoneiser View Post
I don't understand why I wouldn't have a focal length....wouldn't the bellows allow me to have a varying degree of focal length along with the option of tilt shift?
Your effective f stop will change in relation to where you put the pinhole too,
longer extension=smaller f stop shorter extension=larger stop.
I don't know for sure but when you use a smaller than optimum pinhole I think diffraction rears it's ugly head.