I will let our lighting experts chime in here first.
Decide what mood you want first. Dark, bright, grey, blood red.
Never use full color lights, Turn saturation down on them to prevent them nasty bright spots.
Play with the range of a dim light and start off small like 100 - 200 for a table lamp, 500 for a pourch lamp, 700 for a light pole lamp, even 50 for a candle.
Play with the sliders in the Tab TAb mode of test game. change the skys, and notice the color change in ambient. Makes a difference and can add that just right touch. It effect inside stuff also right now. So its part of the factor to think about.
That will get you started.
We have some really talented people that will chime in and continue this for you.
PM sent back.
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