Test the lens on the Z camera and see whether focus is accurate or shows the error programmed into the lens. Why don't you try a more extreme test? Use the dock and program a change that should cause an obvious front or back focus. That's different than fine tuning a lens through a dock because the camera might still need an adjustment if you want to bias focus. It's easy enough to fine tune the Z6 to compensate for that problem. For example when photographing captive owls from close distance, the small feathers in front of the eye act like eyelashes and cause misfocus. But because a lens that needed repair and was focusing that badly still worked perfectly on my Z6, it's safe to say something is going on to use a contrast detect focus step.ĪF Fine tuning can be used to correct lenses, but some people use it to bias focus intentionally. The lens needed repair, and after repair works fine on both cameras. When I tried it on my D850, I found it was backfocusing badly, and even an adjustment of 20 was not enough. I had a Nikon 70-200 that was focusing perfectly on my Z6 for several months. Part of the logic for this was some unexpected testing.
![(82) reikan focal pro lens calibration (82) reikan focal pro lens calibration](https://blog.reikanfocal.com/wp-content/uploads/2020/07/image6-1024x1024.png)
If the adjustment to the lens is not corrected properly, you could program Fine Tuning into the Z camera for that lens or adjust the D850 to remove the need for the original adjustment. So the contrast detect step would usually compensate for the adjustment you made to the lens. My understanding is the Z cameras use a blend of phase detect for speed and contrast detect to fine tune that focus.
![(82) reikan focal pro lens calibration (82) reikan focal pro lens calibration](https://blog.reikanfocal.com/wp-content/uploads/2019/05/Reikan-FoCal-2.9b3.jpg)
I would expect the Z6/7 to focus accurately with a lens that has been adjusted using the dock. Of course this is just conjecture and I would try the lens and see how it performs. If you need to input some camera criteria, then being a different camera it may disregard the calibration entered and the lens is essentially set back to factory adjustment. Having never used the dock, what are the input parameters for the dock when doing the calibration? In other words, what inputs to the dock about the camera used are entered into any criteria that is asked? If there is no camera input asked, then the lens's internal memory may just assume it is any F mount camera that needs the calibration and seeing that it is on an FTZ, then it is essentially assuming it is an F mount camera and apply the settings used. I had a dock when I had my Sigma 35 f1.4 Art but have sold the lens and dock and I never used the dock. If I have micro adjusted my sigma lens using the sigma dock for use on my D850 how will that affect its performance if I use it on a Z camera? Scratching my head a bit thinking of this.