I have heard some (or many?) people talking about the oil diaphragm problem of the Nikkor AF 35mm f/2D lens. The oil leaks onto the diaphragm (aperture blade), and caused the aperture blade sticky and can't open or close smoothly. This may lead to under or over exposure. For negative, one might not be able to detect the differences, for the developer might have corrected the exposure during printing, but for slide this can be pretty annoying. 

    Nikon Japan said that they have corrected the problem, but they didn't state starting from which batch the lens is oil free. Even if you are buying a new Nikkor AF 35mm f/2D lens from shop, your lens might still be the oil problem one as it might be an "New Old Stock". Thus, this page is meant to trace the serial number of which lens is problem free, or at least give some idea to the Nikon owner to which lens is likely to be oil free.

ps: If you don't want your name or any particular to appear above, please email me and let me know. If you have any other information that you want to add, please contact me too.

pps: For those who owned the Nikkor AF 35mm f/2D lens and would like to contribute to this page, please email me with the related info of your lens, either with oil problem or without oil problem. Thanks.