Above you can see an image of the night sky over a small country town called Cowra, in Western New South Wales Australia, about 240 Kms from Sydney, the skyglow essentially removes the view of the night sky.
To the left is an image of the old Sydney GPO in Martin Place. It is an example of excellent building illumination the interesting and remarkable architectural features of the building are well defined with subdued lighting that doesn't spill into the night sky. Also note the "Smartpoles' with full cut-off lighting and the almost zero glare.
The phenomena known as Skyglow is caused by light that is reflected from particulate matter and water vapour in our atmosphere. It reveals the presence of wasted light, without the particles and vapour the light would travel in a straight line and eventually leave the Earth. Instead the light is reflected in all directions until it meets our eyes and causes glare.
All rights for the photos reserved to Sydney Outdoor Lighting Improvement Society.