Added a quick link to the header menu as well as sidebar widgets to access the categories menu. That should make accessing posts related to the lens database easier. You may also use the direct address here: https://jetcityninja.com/category/adapting-gfx/
Adapting GFX: a Quick Note on the Canon EF 135/2L and Some Brain Droppings on the 85/1.8 USM
Eye-AF works pretty well with this combination. Focus is slow, but it's able to find and lock onto an eye. Because of my experience with the X-T3, sometimes my expectations can be a bit skewed; face and eye detect on the 2018 X-T3 is quite good, especially on distant (small) faces as Fujifilm has improved by leaps and bounds in this area. How quickly I forget the GFX 50S is over a year and a half older, with an imaging processor based on the X-Processor 3 design in the X-T2 and not the current X-Processor 4. Combined with other hardware limitations, plus the fact that the latest firmware update was over a year ago, eye AF on the GFX 50S (or 50R, for that matter) cannot be expected to perform anywhere near that of my X-T3.