jeweler53

This is my first post. Let me know if I should be doing it differently.

Does anyone here have experience converting non AI to Ai lenses? I just bought a Df (to replace a 3100 that I really didn't like much) and so far I am THRILLED with it. I was drawn to it because I can use ALL my old lenses.

And no, I don't mind focusing myself. I've been doing it for almost 50 years, and I would rather choose the focus point myself. Auto focus is fine in situations where I don't have time, but manual is great!

Anyway, I have a NIKKOR-Q Auto 135mm F2.8 Lens I might want to convert to AI. I works fine, but of course it doesn't meter.

Thanks in advance

jrh1354 Loc: Dayton, Ohio

There are a few places left in USA that can still do this conversion. Unfortunately, I lost a lot of my goto reminders when my hard-drive went belly-up last year. The conversion involves actual machining on part of the lens and attaching a bracket to interface with the cameras aperture link. Obviously, you won't need the bracket since modern Nikon cameras don't have the aperture link. It could get a bit expensive. Hopefully, other members (Jerry, are you there?) will be able to give you more detailed guidance. I wouldn't do this since the digital cameras have link interfaces that might be compromised by the obsolete interface connections on your old lens. Good luck!

Fotoartist Loc: Detroit, Michigan

Contact John White, Ann Arbor, Michigan. Been doing it for 30 years. http://www.aiconversions.com

jeweler53

One of the advertised features of the Df is that every single f mount lens Nikon ever made will work on the camera. The claim appears to be true. All my other 'legacy' lenses work perfectly!

BebuLamar

You can use the pre AI lenses on the Df and it will meter. It's a bit cumbersome but it will meter. You have to enter lens data and then set the aperture on the lens to match the aperture in the display using the sub command dial.

nikonbrain Loc: Crystal River Florida

Even though there some that still do it on the web ,I still do my own .it is only a lower notch on the aperture ring Easly done with a small file . The rings are aluminum (soft) .There is a place on the internet that gives you the stop and start points in millimeters to file the recess ,best done with the ring off ,if you are handy with tools .I can try and find the site and text later....

alfeng Loc: Out where the West commences ...

Back in the day, the recommendation was to send the lens to EPOI (Ehrenreich Photo) ... at the time, I think the fee was ~$20 plus postage-to-send-it-to-them ...

I suppose that the easiest way to convert the lens is to send it to Nikon ... the fee is certainly more than $20, now.

Because I had the misfortune to buy a new non-AI lens just a few months before the change to AI "coupling" was introduced I opted a DIY "fix" (the "fix" worked on a subsequent FM body which I eventually got which must have been the reason that I bothered to "fix" the lens) ...

If you look at a non-AI lens and an AI lens, you will see that the difference is the perforated indexing prong (to allow some light to fall onto the aperture ring) PLUS a supplemental partial collar on the back edge of the aperture ring; so, you simply need to add a supplemental collar to the aperture ring.

For reasons which I no longer recall, I had an M42 lens mount ring whose inner diameter matched the outer diameter of the particular lens (90mm Vivitar Series 1) which I wanted to modify ...

So, I simply cut a portion of the M42 lens mount ring to "glue" onto the aperture ring (BTW ... after looking at an AI-indexed lens that I had, I believe that I deduced that the one edge should index to f5.6) ...

Armed with the presumption that the indexing collar should mimic the location on a "real" AI-indexed lens, I removed some of the anodization for the edge of the aperture ring (tape the portion which you want to protect!) and then epoxied the partial collar in place.

24+ hours later, I (spray) painted the add-on collar (again, tape the portion(s) which you want to protect!!) ...

DONE!

Fotoartist Loc: Detroit, Michigan

I just saw John White yesterday. He said his Nikon conversion business has understandably fallen off but he is still occasionally taking orders.

nikonbrain Loc: Crystal River Florida

Sorry not true , material has to be removed not added the removal is needed on new digital models starting with the first digital models . If you don't the older pre ai will jam the aperture feeler and possibly damage the cameras .

alfeng Loc: Out where the West commences ...

I have related MY experience ...

AND, I have also related MY observation of MY AI-indexed lenses (most ARE Nikkor).

The aperture ring on subsequent Nikkor lenses may indeed be different; but, the OP's lens is an older lens whose aperture ring certainly had the SAME outer diameter as the one which I amended since THAT DIMENSION was standardized because of the indexing prong ...

N'est-çe pas?

Rich1939 Loc: Pike County Penna.

Relatively in expensive, quality work, quick service.

nikonbrain Loc: Crystal River Florida

This is a notch I filed on a 55 millimeter 1.2 the bright area is the notch , this has to be done on all non ai lenses this a 1969 lens ,all pre ai need this notch ,the start and stop point is all that changes I found the beginning of the notch gets closer to the coupler as the lens aperture gets smaller , in this lens I had to remove the coupler because the starting point was under the coupler and the file job took away the screw holes to hold the coupler.

alfeng Loc: Out where the West commences ...

OKAY ...

I cannot speak to the aperture ring on digital Nikon lenses ....

And, I certainly cannot invalidate what YOU did to make your older Nikkor lens viable on your digital Nikon camera body ...

The OP was simply asking about converting non-AI to AI (vs. later iterations) for use on a Nikon Df body ...

And, that was the raison d'être for my reply as presented.

Comprendez-vous?

Rich1939 Loc: Pike County Penna.

Please ignore some of the bickering. I recently had John White modify an 85mm for me. for the $25 he charged at the time it wasn't worth me attempting to do my self. I'll dig up his e-mail address and PM it to you.

BebuLamar

With the Df there is no need to convert