Nikon has released firmware updates for three of its Z-mount lenses that, amongst other updates, add the ability to turn on linear focus ring rotation, making it easier and more accurate to pull focus by directly linking the rotation of the ring with the focus distance, regardless of the speed at which the ring is rotated.
Nikon’s Z mount mirrorless lenses utilize a focus by wire (FBW) system in autofocus mode, which employs an electronic motor to move the lens elements in and out of focus. This differs from a manual focus ring rotation manipulating the elements and moving them back and forth with a mechanical ring rotation. The updates were in response to user complaints that the focus by wire or non-linear focusing in Z mount lenses becomes laggy and prone to overshooting their focus targets. By adding linear manual focus, pulling focus becomes more accurate and easier to implement.
The firmware update is available for three lenses: Version 1.10 for the Nikkor Z50mm f/1.2, version 1.20 for the Nikkor Z 24-70mm f/2.8 and version 1.10 for the Nikkor Z MC 105mm f/2.8 VR S lenses.
Nikon notes that the firmware updates expand the manual focusing capability by adding a linear focusing option when the camera is set to manual focusing mode. In addition, the firmware adds support for [switch focus/control ring roles].
More info on firmware updates from Nikon’s download page:
Firmware version 1.10 for the Nikkor Z 50mm f/1.2 S
Firmware version 1.10 for the Nikkor Z MC 105mm f/2.8 VR S
Firmware version 1.20 for the Nikkor Z 24–70mm f/2.8 S