Researching/Referencing lighting

I grabbed some reference material for the exterior lighting. The first task ive set myself up for is to produce the sky for the exterior. Ive come across a great tool in Maya, called Sun and Sky System, which creates a horizon line for you, however you still have to do a lot of tweaking to the tool to get colours correct to what im looking for. These reference pictures will help me a lot, as its the kind of mix of colours i am looking for, a dusky mood.