How is the A7 III autofocus in extreme low light?

[Canon_dork]

Does anyone have any experience with how well the A7 III autofocuses in extremely low light? I currently use Canon gear, but I really like a lot of the features of the A7 III like face and eye autofocus. However, I've gotten some conflicting impressions about how the Sony autofocus performs in low light, and I mean really low light. With my Canon 5D, I frequently take photos at the following settings:

 

1/100 second shutter

f1.2

ISO anywhere from 10,000 to 20,000

 

I'm talking about situations that take those kinds of settings to get a good exposure. Picture an indoor room in a house, at night, lit by only one standard light bulb. Can the A7 III focus quickly and accurately under those conditions at f1.4? Or does it struggle? Admittedly, the Canon is not great in such low light. Even if it does achieve focus, it's not always accurate, but it does manage some of the time. But, I really like some of the features of the A7 III, and I think it's cleaner at higher ISOs than Canon, so I've been thinking about giving the Sonys a try.

 

But the specific attribute of autofocus in low light and how well the advanced features like eye autofocus works in those conditions is not something I've seen talked about in reviews.

[tonibaz]

I don't have an ultrafast lens but with a Sony FE 85 1.8; shooting at 1/90 - f:1.8 - ISO 20.000 no problems; even at ISO 204.800 depending of the object it struggles sometimes, apart of the huge amount of noise ...