T4 Non-AI Adapters (Sort Of) Work With AI Nikons

[k5083]

<p>Recently I acquired a few Nikon AF cameras from the 1990s. One of them was an N60, a camera that left me so unimpressed that I felt willing to play with it with some pre-AI Nikon and third-party lenses, despite the dire warnings we have all seen that mounting pre-AI lens on your late-model camera will damage it.</p>

<p>In so doing I learned what appears to be a Fun Fact about Vivitar/Soligor pre-AI adapters for T4 lenses that I have not seen posted here before: so far, it appears that T4 lenses with these adapters will mount on late-model Nikon cameras without damage and, up to a point, they work.</p>

<p>The thing that damages an AI Nikon camera when you attach a pre-AI lens is a black outer cuff on the pre-AI lenses which extends back a bit past the mount flange and will break the aperture indexing tab on the camera if there is no AI cutout. T4 lenses (at least the ones I have tried) do not have this cuff. When mounted on a camera using the non-AI T4 adapter (which is the only Nikon adapter made for T4), the lens body stands slightly proud of the front of the camera. Enough to clear the aperture indexing tabs, at least on the cameras I have tested, which so far are the N60, N70, N90, N6006, and N8008.</p>

<p>Besides mounting, the T4 lenses work on these cameras to the following extent. Auto diaphragm operation works on all cameras. Depth of field preview works where available. Nikon's manual focus confirm, or "electronic rangefinder" display, works on the same cameras where it would work with an AI lens. Metering works on the same cameras where it would work with an AI lens, except that your metering value will be for the lens wide open, no matter what you have it stopped down to, since the camera can't detect that it's stopped down. Some cameras like the N60 will not meter with an AI lens because they insist on electronic communication with the lens, and of course those won't meter with a T4 either.</p>

<p>There are various ways you can cope with the fact that the metering value is for wide open. If you actually shoot wide open, the meter value will be accurate. If you stop down, you can set exposure compensation (or, alternatively, ASA) to compensate. For example if you're shooting an f2.8 lens at f8, dial in +3 stops of exposure comp and the metering will be accurate. You can even shoot in aperture priority automatic this way, as well as manual. Of course you have to remember to change the exposure comp value every time you change the aperture. How much of a hassle that is depends on how and what you're shooting. Also, of course, you could just meter for wide open, calculate in your head how many stops down you are, and set the manual settings accordingly (i.e., in-brain exposure compensation).</p>

<p>I was hoping that on cameras with a depth of field preview I could meter with the preview engaged, which should give accurate exposure values, just like using a pre-AI lens on an FM. However, it turned out that my N8008 and N90 switch off the meter when the preview button is pressed, so it didn't work. :(</p>

<p>This is quite good news for me because it opens up about a dozen lenses, some of them quite good, for use with the newer Nikons. In principle I don't see why it wouldn't work all the way up to current models. However, I emphasize, TRY THIS AT YOUR OWN RISK and don't blame me if something breaks. For all I know, I've already broken my own cameras and don't realize it yet.</p>

[JDMvW]

<p>Interesting. Thanks for sharing.</p>

<p>I personally only buy non-AI Nikon camera bodies these days (still looking for my all-black Nikon F2 with the plain prism for an affordable price :). My older Nikon non-AI bodies were bought new before AI.</p>

<p> </p>

[User_502260]

<p>There was an AI adapter for the later TX lenses. The closest I ever got to one was an eBay auction, which I didn't win. I have plenty of pre-AI Nikon bodies and several Vivitar TX non-AI adapters. I have thought about getting one of the non-AI adapters modified. </p>

[JDMvW]

<p>That's an interesting idea, Jeff.</p>

<p>I wonder if the old T2 mount adapters could be AI'ed? As I say, I don't personally have any AI or later Nikons, but it would be sort of intriguing to mount all those old Spiratone pre-set lenses on later models.</p>

[k5083]

<p>I have the TX AI adapter. Because of Nikon's external coupling system, it is one of the more intricate and fussy TX adapters, with a moving ring at the back to push the AI tab around. You could mod a T4 non-AI adapter to take a TX and physically get it on the camera, but I don't think it would be practical to make it work like an AI lens, with accurate metering.</p>

<p>You must know that the way to get a TX AI adapter cheap is to look for an auction where it is stuck to the back of an undesirable lens, like the 90-230. They aren't as common as some of the others but they do come up if you're patient.</p>

<p>I'll probably be using my T4s more than my TXs with the Nikons. The T4 adapter is a lot less fiddly to get onto the lens, and I tend to collect primes in T4, which I find as good as the TX primes, and collect only zooms in TX.</p>

<p>You could make a T4 lens work as an AI by attaching a longish tab to the aperture ring that reaches back over the T4 mount and engages the camera's AI tab. Trouble is you'd be modifying the lens, not the adapter, and it could interfere with use with other adapters/cameras. Maybe there's some way that you could make a tab to attach to the T4 adapter rabbit ears to do the same thing, but it would be hard, because you'd need quite a long tab and there's not much to attach it to.</p>

[walter_degroot]

<p>someone who is known to be handy at working on cameras told me in an email; that he had MADE a add-on bracket for some of his non ai nikon lenses<br>

I will not mention his name because he would get a thousand requests</p>