Below is a list of lenses that have been tested with the FX9’s advanced autofocus system. Generally any Sony E-mount lens will work just fine. The Sony G series lenses are good and the G Master series tend to be even better.
For third party lenses and adapters the situation is much less clear, so I have decided to list the lenses I have tested and invite others to contribute to this list via the comments area. The list is not exhaustive at this time but I will try to keep adding to it as I am able to try more lenses and and different adapter combinations.
Inclusion of a lens on this list is not a guarantee that it will or will not work, it is simply an indication of how it worked for me or anyone else that adds information about their own experiences. I welcome updates and any further information from any lens or adapter manufacturer.
If there is a lens you have tested on an FX9 please let me know via the comments how it worked so it can be added to the list.
KNOWN TO WORK WELL:
Sony E (super 35mm) FE (full frame) lenses, G and G-Master including Zeiss ZA series. G and G Master tend to have the best AF performance.
Tamron 28-75 f2.8 Di III RXD E-mount.
KNOWN TO NOT PERFORM WELL:
Sigma 20mm f1.4 ART native E-mount (very slow AF, hunting, contrast only?).
Sigma 85mm f1.4 ART native E-mount (very slow AF, a lot of hunting).
Sigma 20mm f1.4 ART Canon EF mount on metabones, comlite or viltrox adapters. Very slow AF, not really useable (MC11 not tested yet).