I've been doing renders of scene with various polished metal objects, and they're not coming out right. At least, when I compare the render of a polished metal cylinder with a real one, they don't look right. Heck, there's any number of polished metal cylinders on eBay -- do a search in the photography stuff for "Jupiter". Check the materials settings, and the diffuse colour is white while the specular colour is light grey. And there are reflection effects on top of that. I'm beginning to wonder if there are too many too bright colours, and the different effects are swamping each other. And is white, or black at the other extreme, too extreme? It you start from white, where are the highlights to go? Start from black, and what is left for the shadows?