[janoskiss (Steve H)]

Originally Posted by Argonavis

Love the map and your zeal to use every available dark sky weekend. Now if only I could dispense with the family...mmmm.

Thanks! I plan to visit all the red labelled locations eventually... with my scope of course

Do you know if there is a genuine difference between the grey areas on the map and the black areas in terms of limiting magnitude?

Each successive colour in the contour plot represents a 3-fold decrease in light pollution background, which would corresponds 1.2 mag increase in limiting magnitude. Which checks out, because that's about 5 magnitudes difference between near the central part of Melbourne and somewhere like Lake Mountain.

Of course the 1.2 mag increase in limiting magnitude is not when you step across the line from the grey into the black but when you go from say blue-grey boundary to grey-black boundary. In the black areas, presumably the best places are likely to be those furthest from any grey areas.