Hi there, Not sure how to phrase this, but I have a thought/question about lenses and image circle when close focussed: As a lens is focussed on increasingly smaller distances from the film plane or camera, the distance of (parts of) the lens is moved away from the camera, either by the focus ring, extension tubes or bellows unit. Q. As the lens moves further away, does the image circle (at the film plane) get bigger? If so, and one is using less of the complete image produced by the lens, is this reducing the resolution of the lens? Well, I guess that the resolution of the lens is still the same but could one be using 'less' of the resolution as a lot of the image from the lens is outside the area of the film plane? Not very well put I know but perhaps a summary thought could be; would the captured image get worse as the lens is focussed closer esp with tubes and bellows? Thanks for staying with the rambley question - any thoughts/answers welcomed! Sim2.