Quote - How do you add reflection properties to, say, a stone or wood floor? Is it just increasing the glossiness? To me all that would do is concentrate the specular highlight. 

The success in working with Lux is to remember that objects work like in real life. So you don't act of the reflection properties, like you would do in Poser, where you add a reflection map. Refl.maps are needed in Poser because Firefly doesn't computer reflections from the surrounding environment. Lux does. Reality completely ignores the reflection maps as they are not useful with Lux.

So, you act on two parameters: specular color and glossiness strength. The spec.color's brightness indicates how much light is reflected. Brighter colors reflect more light. A pure white will reflect 100% light back, which is completely unreaslistic. No surface in nature does that, not even a mirror. For most cases a brightess value below midpoint is generally good. Midpoint, if using grey, is 127,127,127.

The specular strength is the level of polish of the surface. 0 is dull, 10,000 is mirror finish. You pick the value that fits your image. Reality gives you a good starting point from analyzing the original material, but you might want to change that.

Next you need to have something to reflect. If you place a sphere on the ground with nothing around then there will be nothing to reflect. If you place objects and an evironment (castle, spaceship, woods) then the environment will be reflected on the object in a very realistic way. 

Hope this helps.

Paolo

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