http://www.lightpollutionmap.info http://www.lightpollutionmap.info has much higher resolution data, down to tens of metres. You can also choose the dataset by

http://www.lightpollutionmap.info http://www.lightpollutionmap.info has much higher resolution data, down to tens of metres. You can also choose the dataset by year - choose the "VIIRS 2017 March" dataset for the best detail. Data comes from the Visible Infrared Imaging Radiometer Suite (VIIRS) satellite [1]. For example, with the extra resolution I managed to find a dark patch near the train line in between Waterfall station and Helensburgh south of Sydney - the darkest sky until you go far past Wollongong. [1]: https://jointmission.gsfc.nasa.gov/viirs.html https://jointmission.gsfc.nasa.gov/viirs.html