Old manual focus Nikon lense: Will it work on a modern auto-focus DSLR?

The lens should fit and work in manual mode. As others have said, no autofocus, and metering may only work in some higher end DSLR's that can interact with some of the mechanical linkages to know how many stops down from wide open the aperture ring is set. You can use the sunny 16 rule or use meter readings with other lenses to get an approximately good setting, and then trial and error to get an optimum setting.

AI and AIS lenses fit the D3xxx and D5xxx, but don't allow metering (or autofocus, of course) making them little better than Canon FD lenses (which won't fit EOS cameras at all).

Of course, Pentax offer limited modes (Av and M) with K-mount MF lenses, and all modes with Ka-mount ones - and even Av and M modes with M42 screw mount lenses and a suitable adapter - but nobody seems to notice the oldest SLR manufacturer in Japan these days.

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