Yes, but, for the most part, they were installed by repair shops or by a Nikon service facility. So, they were still not really AI. Even the final batch of 85/1.8 K version Nikkors were still not real AI lenses, even though they all came with a #37 ring attached from the factory. They don't have the lens speed sensing post.

The only "real" AI lens I now own happens to be a factory AI'd 28/3.5 Nikkor-H that I had someone modify the rear element baffle so it wouldn't damage my previous F4 body. Turns out that the modified section correctly engages the cam inside the mirror box and registers a max. speed of f/3.5... It's still not a real AI lens, since it wasn't made between 1977 and 1982, instead dating from the 1969-70 time period.

Re: value, KEH seems to value even the milled aperture ring AI converted lenses higher than the unmodified lenses. Granted, anything with a factory style AI ring is called a "real" AI lens by them. Even when it's blatantly obvious that the lens isn't.

I usually troll evilBay and KEH, looking for ugly condition factory AI'd lenses (or in the case of K-version lenses that had an AI version, factory AI lenses). Then, I find a nice condition pre-AI lens in the correct serial number range and do the switcheroo. Takes about 10 minutes to do on the more complicated lenses, and maybe 3-5 minutes on the easy ones. Sometimes less, like on the 135/3.5 late model Q and Q.C lenses.


Quote Originally Posted by kitanikon View Post
Re: John_Nikon_F and Xmas...some PRE-AI "K" lenses were available with factory AI aperture rings...e.g. 135mm/2.8 Q.C and 85/1.8K, both of which I have...I think they are less available than their non-AI versions, so they'd be worth more I should think...

...and I would think that the market value of lenses converted with the "cut" notch at the rear of the aperture ring (I have one of those too) would likely be worth less than OEM...but its value to the owner/user is another matter of course....

In some cases it may be cost-effective to convert a other cases it may be cheaper to get the factory-AI version and sell the non-AI lens.