My two favorite Nikkor lenses are a fisheye and a micro (nikon's usage for macro if m </= 0.5):
nikkor 16mm f/3.5 fisheye, although the Pentax 16mm f/2.8 is comparable--I have both. My feeling is the Nikkor is nicer but I am comparing use on a D700 versus cropped sensor Pentax, so not really much basis.
nikkor micro 55mm f/3.5 or 2.8--I had the f/3.5 and have the 2.8. They are both exceptional (and this was mostly for non macro usage), although I preferred the f/3.5. Compared to the closest Pentax offering--the 50mm f/4 (I have the K version)--I think the Nikon is better (actually much better)**--although there is no A to B testing and I did not use the Pentax much--and did/do use the Nikon a lot but only on film.
Actually, the 28mm or 35mm PC lens by Nikon are reasonable in price now, and are smallish sized lenses. I have both. I especially like the size and design of the 35mm f/2.8. It would be a good general purpose lens to have for scenery/travel with the advantage that it also is PC. I just have not had the chance yet to use it this way--although on the cropped Pentax sensor 35mm is less desirable vis-a-vis PC.
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** I have been thinking about what I said and it is w/o much basis. I have only very limited use of the Pentax 50mm f/4 macro--basically of a city scene that I take with all my lenses--and the Pentax seemed to be dull/lack contrast. So let me just say I like the Nikkor 55mm micro, and I have too little experience w/ the Pentax to compare them.
Last edited by dms; 07-18-2020 at 09:33 PM.