Wed Jan 19, 2022 11:58 pm
This lens doesn't officially support auto focus or focus control according to Fuji. However, we are able to drive it in some way...
If you are using the camera auto focus, or are controlling it from a switcher then clicking the front focus ring on the lens forwards into the 'Macro' position will allow it to hold focus after adjustment which will stop the behaviour you are seeing. It will allow it to auto focus, or to adjust focus from the LANC or switcher and then will hold that rather than going out of focus.
As a side note, when the Blackmagic Focus Demand is being used with URSA Broadcast G2 it takes over the focus control totally on the lens and so will hold this position without needing to use the 'Macro' ring work around. Unfortunately as the USB-C port hardware on the URSA Broadcast (G1) does not have power delivery on it, and as the focus and zoom demands were not even conceived or designed when the original URSA Broadcast was designed they will not be able to work together.