Bortle scale of
light levels
class 1 - Excellent Dark sky site
class 1 - Excellent Dark sky site
Class 2 - typical dark sky site
Class 2 - typical dark sky site
Class 3 - rural sky
Class 3 - rural sky
Class 4 - Rural/suburban transition
Class 4 - Rural/suburban transition
Class 5 - suburban sky
Class 5 - suburban sky
Class 6 - bright suburban sky
Class 6 - bright suburban sky
Class 7 - suburban/urban transition
Class 7 - suburban/urban transition
Class 8 - City sky
Class 8 - City sky
Class 9 - Inner city sky
Class 9 - Inner city sky