ISO 6400 JPEG, night

In very low light you do start to see more traditional artifacts at higher ISO sensitivities in JPEGs, including hot pixels and loss of detail from noise suppression. That said, I was able to get nearly the same exposure at ISO 250 (albeit at a much slower shutter speed) which was exceptionally clean.

(1/2200 sec, f1.4, ISO 6400, spot metering, AWB, 35mm lens)