Nikon Z6, Z7, Z50 AF Fine-Tune Firmware Changes

Update 16th Oct 2020: Nikon have released new firmware which fixes the issue described in this blog post. The fixed versions are Z 6/Z 7 version 3.12 and Z 50 version 2.02 (download links below).

With the release of the latest firmware for their Z cameras, it seems that Nikon have partially removed AF Fine-Tune as an option for Z-mount lenses.

Fixed Firmware

UPDATE (October 2020): Nikon have just released new software which fixes the AF Fine Tune issue described in the post below. We’ll leave it for reference, but you won’t see the problem if you use the following or later firmware:

Nikon Z 6 version 3.12 (download)

Nikon Z 7 version 3.12 (download)

Nikon Z 50 version 2.02 (download)

What’s the Issue?

The remainder of this post is purely for reference – the issue is fixed with the firmware linked above.

We had some reports from FoCal users of Nikon Z cameras suddenly not actioning AF Fine-Tune values, with FoCal reporting that the value was always set to 0 when an adjustment had clearly been made on the camera menu.

During a FoCal autofocus calibration, the following screen would be shown after (correctly) applying the AF Fine-Tune setting through the camera menu system:

Our investigations have shown the following to have changed on the Nikon Z6 (firmware 3.1), Z7 (firmware 3.1) and Z50 (firmware 2.01, possibly in 2.00) cameras and almost certainly the Z5 as well (although we haven’t yet confirmed this):

• Z-mount lenses: Although the AF Fine-Tune menu is present and active for all lenses, a change to the Lens Specific AF Fine-Tune value will not be actioned for Z-mount lenses.  Whatever the value specified on the camera, there will be no adjustment made and the image metadata will report that AF Fine-Tune is set to 0.
• F-mount lenses with the FTZ adapter: There is no change to the original operation of AF Fine-Tune with F-mount lenses used with the FTZ adapter* – therefore a lens specific AF Fine-Tune value will be appropriately applied to the Z mount lens.
• The Default AF Fine-Tune option – applied a fixed value for any lens attached to the camera – still allows adjustment of AF Fine-Tune for both Z-mount and F-mount lenses.  

* tested with FTZ mount adapter firmware 1.00 and 1.10

The following table summarises when a Nikon Z7, Z6, Z5 or Z50 with the new firmware will apply or ignore the AF Fine-Tune value set using the menu system:

	Lens Specific (Saved Value)	Camera Specific (Default)
Z-mount	Ignored	Applied
F-mount (with FTZ)	Applied	Applied

Using FoCal with new Nikon Z firmware

Nikon have also modified the way lens information is stored within image files and current FoCal releases will not decode the new format, some information (e.g. lens name) will not be correctly determined.

This has been fixed in the development branch of FoCal 2020, and the next beta release will allow continued testing of Nikon Z cameras.

Until the next FoCal 2020 release, in order to calibrate with full lens information available for history/reports in FoCal, users would need to revert camera firmware back to a previous version – version 3.0 for Z6 and Z7. The Z50 would need to revert to firmware 1.00 and Nikon don’t release the very first firmware versions publicly as the cameras are already supplied with this version installed.

When the new release of FoCal is available, the following applies:

Calibration

We suggest the following change for calibration of Z-mount lenses with FoCal:

• Run the Calibration test as before, but use the Default AF Fine-Tune option on the camera to change the value.

If the lens requires an AF Fine-Tune applied of more than 2 steps (i.e. if lower than -2 or greater than +2), we recommend sending the lens to Nikon for adjustment*.  

* Technically you could note down the calibration value required and apply it to the Default setting each time you use the lens, but this is error prone and risky as you are likely to change lenses and forget to adjust the value.

MultiTest

As MultiTest is a tool for measuring performance rather than calibrating, it’s perfectly acceptable to run the test using the Default AF Fine Tune option to change the value during measurements.  This will give an accurate set of results for calibration, focus consistency, focus shift etc:

Other Tools

All other tools within FoCal are unaffected by this change.

Why have Nikon done this?

29th September 2020: With the release of their latest firmware for the Z6 (Firmware 3.11) and Z7 (Firmware 3.11) cameras, Nikon have confirmed that this is indeed a bug. The following information is available on their download pages:

Important
An issue has been identified in firmware versions 3.10 and 3.11 in which fine-tuning values selected for AF fine-tune > Saved value are not correctly applied when pictures are taken. A fix will be made available via the Download Center as it becomes available. We apologize for any inconvenience this may cause.

Note that this comment is NOT on the Z5 Firmware 1.01 download page, and there is currently no update available for the Z50.

This is great news – the apparent removal of the feature appeared half-hearted and removed useful functionality, so although annoying that it is broken at the moment, it’s good to know you’ll be able to calibrate native Z lenses easily again soon!

Original content of this post

The following is the original content of this post before we had word that this was a bug…

21st September 2020: We have asked Nikon for comment and as of 21st September we have the following response:

Thank you for bringing this matter to our attention.

He are currently performing tests on our end to further understand this behavior of the Z series models

We will get back to you with further information, as soon as available 

I apologize for the delay this may cause.

It is possible that Nikon may have decided that Z-mount lenses do not require any calibration, so have partially removed the functionality, but it’s also possible that this is just a bug.

Looking at FoCal IQ data for Nikkor Z-mount lenses, the calibration values are among the best of all the lenses in our database, all Nikkor Z-mount lenses have a value of 92 or greater (out of a maximum of 100):

Compared to F-mount lenses, you can clearly see that the Z-mount system (i.e. Z-mount lens on a Z-series camera) have far less need of calibration (the very best F-mount lens scores 84 by comparison):

The Calibration details of the Nikkor Z 24-70mm f/2.8 S shows the typical adjustment for both ends of the zoom range is close to 0:

and the distribution of required AF Fine-Tune values is small:

Having said that, it’s not totally insignificant, with apparently more requirement for calibration at the telephoto (70mm) end, there would definitely be a small improvement in overall quality with the appropriate AF Fine-Tune value applied.

Nikon’s change is somewhat confusing, their firmware release notes do not mention the removal of AF Fine Tune functionality, or disable the AF Fine-Tune option when a Z-mount lens is attached. You can merrily go ahead and change the value for a Z-mount lens – thinking the adjustment is being applied – and the camera will be completely ignoring it.

Based upon the discovered functionality in the new firmware, Nikon do allow F-mount lenses to be calibrated and it appears it wasn’t a mistake to leave AF Fine-Tune as an option (e.g. there are 2 calibration options on the D780 – one for Live View and one for Non-Live View operation), hopefully the AF Fine-Tune option on the Z-series cameras won’t be removed completely!

We will report back with any response from Nikon, and we’ll have a new release of FoCal 2020 soon for use with the new Z-series firmware.