On our trip up to Cairns we visited my wifes cousins who own a grazing property near a Carinda in NSW. Carinda is about 50 or so kilometers from the property and Warren is the next biggest town and that is 130km away. I recorded readings with my SQM of 21.8-21.9. It was very dark and very quiet.
The video covers a couple of hours with frames being taken over 30 seconda with a 1 second interval. I was using ISO2500 at f2.8 on a D3 with a 14-24 f2.8 Nikkor lens.
Click here for Video
I have attached some stills from the video which are untouched.