Nikkor adapter for NEX-6
I've had very good results with a Fotodiox adapter and the Nikon 35 f/1.8 on my NEX 6. It was under $40 on Amazon and you can adjust aperture, but keep in mind that focus and exposure are manual, just like in "the old days". But the NEX 6 offers plenty of focusing assistance with focus peaking. I wrote about my experience with it here: Sony, meet Nikon. The 35 is the only lens I kept from my DSLR outfit and I'm glad I did. Good luck!