AF Adapters for the Z Series.

Discussion in 'Nikon' started by mike_halliwell, Oct 25, 2020.

  1. A 500mm or 600mm would need a lot of extension to focus over a useful range of distances, so I don't think this would be useful with them but mostly shorter focal length lenses. Are the lenses unrepairable?
     
  2. Yup, sadly no spares available.

    I was thinking for lunar or other long range stuff. Maybe enough extension? Although I guess if I preset the MF helicoid to 'near' enough the focus range may be OK. Bird on nest maybe? or on beach tide-line?
     
  3. Do I get this right? You put the lens on infinity and the adapter then moves the entire lens back and forth to focus? Negating all the things the lens designers incorporated into the lens like close-range correction and the like? Or do you have to set an "approximate" distance first - and then let the adapter take over?
    Even for a 600mm lens, isn't the moon at "infinity" anyways?
     
  4. Yes.... bit like the TC1.6a

    All true, except the lens focuses to infinity and beyond...:)
     
  5. Ah, the Buzz Lightyear of lenses!
     
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  6. I hope it's wired a bit better than the TC-16A. Even with old AF film Nikons the TC-16A didn't work very well, either optically or AF-wise, and needs modification to work with a DSLR.
     
  7. Look at the picture of the adapter it appear to me that the adapter turn the Leica M focusing ring via the rangefinder coupling. And thus I think it's much more difficult to do the same with AI/AI-S lenses.
     
  8. Here's what's being provided by the link in the OP: Focusing is performed by shifting the lens along the optical axis using an electric drive built into the adapter. That operation is clearly visible in the link Mike provided.
    In any case, I would have found it highly unlikely that the rangefinder coupling mechanism of an M-mount lens could be used to move the lens helicoid. So it seems to be as I said - whatever mechanism the lens designers implemented to apply corrections as the lens is focused closer is lost when using this kind of AF adapter. It also doesn't appear to need presetting to a certain distance as the TC-16A did. Though it might benefit from it. Some Leica lenses have a rather long focus throw to allow precise manual focusing - I doubt such a long focus throw can be mimicked by the rather limited range of motion the adapter provides. Given how easy it is to focus these lenses on a mirrorless cameras, I think that AF adapter is rather pointless.
     
  9. I think that's the crux of the thing.

    AF via the adapter is never going to be fast enough for moving subjects. But precision for static subjects is effectively automated rather than fully MF. Focus Peaking may well be easier to judge than by eye too.
     
  10. I found focus peaking to be too imprecise - but the instant magnification option offered by many/most mirrorless cameras really helps things along when shooting something static.
     
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  11. ShunCheung

    ShunCheung Administrator

    These adapters need to include a robotic arm to rotate those the focusing ring on those old manual lenses. :cool:
     
  12. or just employ a focus puller....:p
     
  13. Now about the focus puller! I don't think the puller has the viewfinder so he would have to focus via the scale? I meant the real puller in movie shoot.
     
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