Adapter for screw mount lens for nikon d5100

[SuthrnFlwr]

I found 2 lens at an antique store and I knew they wouldn't fit but their quality was just too good and the price too cheap to pass up. They're both made by zykkor, I've never heard of them before. One is "wide angle lens auto focus range 6ft to infinity made in Japan afcor" and the other is "telephoto lens auto focus range 6ft to infinity made in Japan afcor". They're both the old screw mounts.
So my question is what adapter would be best to get so I can use these lens on my nikon d5100? Thanks so much!

 

[Gavjenks]

zykkor appears to make lenses in a wide variety of mounts. Which means this isn't really enough information to say for sure.

However, if it is a threaded screw mount, there's a decent chance that it is T-mount, in which case you would be in luck, as there are bazillions of T-> Nikon adapters, and they do not degrade image quality at all.

If you want to be sure, though, take photos of the mounts, or better yet, take it in to your local camera store, and test out a T mount before buying, or ask them what they think.

In the future: If you have your camera with you when you see a deal like this, do the following to see if an adapter is possible (without adding more lenses which will be very expensive or degrade the optics):

1) Turn the new lens to infinity focus
2) Walk over to the window or whatever where you can see an object very far away
3) Take the lens off your Nikon
4) Hold the other lens right up to the mount of your camera, and slowly move it further away and closer again, by an inch or two down to zero distance.
5) If at any point, the image appears in focus through the viewfinder, then there probably exists a cheap and non-degrading adapter to your camera from that lens. If not, I would avoid buying it (it is either non adaptable without more lenses in between, or the tolerance is so tiny that any adapter will be precision machined and very expensive)

 

[SuthrnFlwr]

Yea unfortunately I didn't have my camera with me at the time but I could tell the lens wouldn't fit without a little help. And if I couldn't use it at all I know some friends that still have those old cameras and I could just give them to them. Thanks for your help! I'm going to find a local camera shop and take it with me and see if they can help me or recommend what I should do.