If a scene is obviously set outdoors (and I'm assuming a planet with a basic minimum of one sun, here) and there are eight different light sources, that would be too much lighting.    Also, though, a professional portrait photographer, in my admittedly very limited experience (people don't ask to take my photo all that often), makes do with a lot fewer lights than some Poser lighting sets that I have seen.  

It is possible to kill the "realistic" effect by having too many light sources.