Details:
No scratches on the glass
No cleaning marks on the glass
No fungus
Aperture ring smooth in operation
No oil on blades
Diaphragm operating correctly
A note about dust:
Dust is everywhere in the environment, unless one lives in outer space. Occasionally new participants to photography believe that dust in a lens is a fault and question us about it. It is impossible to find a used lens without dust, and even new lenses have some dust. Dust is out of the photographic plane and simply will not affect a photograph. The only dust that will affect a photograph is that on a DSLR camera’s sensor which is in the photographic plane. Indeed, there will be some naturally occuring dust floating in the space between the lens and your camera’s sensor and this will not affect a photograph as it is 'averaged out'.
Dust is only a cosmetic issue and does not affect photographs. For this reason, we do not mention internal dust in a lens unless there is a lot of it, or if there is a large particle.
