I recently purchased a Sony 35mm F1.8 lens (SEL35F18F) and paired it with my A7C to make this review.
The low light performance is very good, but at the end of the video I was overly optimistic about the low light performance (I literally shut all of the lights off), as expected the ISO ramped up and caused some grain.
It still looked sharp and clear with very minimal lighting and I am looking forward to playing around with background lighting when I use it again.