I am looking for some advice on how to improve the colour of the sky during night time photography. At the minute I take most of my photographs in central london and the sky colour can vary by a large degree some deep black, some a blue colour and others sometimes appear a slightly polluted colour. Ideally I would like to take photos that show the sky with a deep dark colour.
I am wondering if it has something to do with camera settings or whether I should be looking at the night time conditions whilst taking the photographs. I also use Photoshop to edit the photographs so if anyone has any tips on how to improve the sky conditions this way that would be great.
A generic rule of thumb is to manage as much as you can in camera and avoid post-processing as much as possible.
In order to capture the sky properly you will want to make sure to point at the sky when getting your camera to evaluate the exposure, lock the settings and recompose.
You may also want to shoot RAW in order to be able to play with the White Balance settings in post and see what works best. You probably would need to use a Custom White Balance otherwise.