I am trying to make a night map from space - http://svs.gsfc.nasa.gov/vis/a030000..._composite.png

I want to mimic that look.

I tried using a brush that made spread out pixels and dots, but it's pattern is always the same. Is there anyway to make the patter it makes random (CS6). Or is there a brush I can download for this?

The attatched image shows the problem with the uniform patterned brush. It just doesnt look natural.

What is the best course to go about for making night cities?
Untitled.png