I created this model about three years ago, and at present the full version is buried somewhere on one of my old hard drives, I remember using fog and luminance lights, but have not got the foggiest how I put it all together. I have achieved good results with lighting, but have always had to put a lot of time into it, especially getting to grips with luminance lights. Anyway, to cut a long story short, is the usage of fog with lights a better method to observe the spread and boundaries of lighting in general, so much better when you can actually see the beam or point light extents while experimenting. If you have any examples or ideas that will be sufficient for a starter, please post on this thread.
See below for my early example of a pipefitter and a welder , for which I created a robot to serve as a model.
Sorry it is a small image, but will have a look for the original in the next couple of weeks.