i use Night Vision + Brightness down to 1
I read that, too. Unfortunately, I got confused when I read it the first time because it makes no mention as to "why" a Brightness setting of 1 is optimal and how it relates to the new Enhanced Night Vision and/or the new "Sports Mode." So, you are left in the lurch (once again) having to figure things out on your own.
To get the better image quality at night, Enhanced Night Vision needs to be "on." However, I've found no way to use "Sports Mode" in combination with "Enhanced Night Vision" without obtaining your results - absolutely grain to the max, destroying the image quality overall.
Apparently, that new Sony Starvis CMOS sensor is working overtime in "Enhanced Night Vision" mode. So, if you add "Sport Mode" and run Brightness above 3 or 4, the ambient light being captured through the lens and digitally augmented (processed) is not being handled very well at 60fps. At least not in my camera. When I downgrade to something "Sport," I can then use "Enhanced Night Vision," run Image Quality at "High" and Brightness around 4. However, the result is not as snappy as advertised. Yes, it does come out much brighter at night
as compared to the 650s. But, it is still somewhat grainy in the final video. If I run the same config and drop the Brightness to 1 or 2, then final video brightness seems only marginally better than the 650s.
In my cameras, it seems like the only way to achieve that dramatic difference in Night Vision brightness is to run Brightness up to 4 and suffer with massive grain which cancels out image quality overall. It is like I can't win for losing.