In reading about different rendering programs I get confused by the differing terminology. For example, I assume that "specularity" is the same as Carraras "shininess". How does "diffusion" relate to Carrara? Is it the same as "color"? If someone says "use a diffusion map" should I use a texture mixer in the color channel? Thanks in advance.. Ed

In both lightwave and c4d, color and diffusion each have their own separate channels. My guess would be that using multiply in the Carrara color channel (to multiply a color in source1 against noise in source2, for example) might accomplish basically the same thing? In general I think Carrara has a rather flexible/powerful material system although (especially at first) you can strain your brain trying to predict how things are going to turn out when you start mixing things (I think some of the higher end programs give you a visual, node-based overview of what's happening with your shaders and some even let you work at that level when building shaders and I wonder if something like that could be done for Carrara).

Diffusion roughly translates over to Highlight. While there are several work-arounds, Carrara does not currently handle true diffusion. Diffusion can be defined as "fuzziness" of reflected light or how sharp and clear the light bounces off of the edges of an object. This also impacts reflections themselves; whether the reflection is a clear duplication of the image or blurred like it would be on brushed aluminum. The main work around that I use is to apply a grunge map or some kind of irregularity into the highlight channel to vary the brightness of the reflected light. Then that combination is again repeated in the reflection channel.You can also play with variations of that in the Bump and Shininess channels if you like. Hope that this helps a little. Mark

Mark, it works for me. Referring to Amorphium, your definition would fit a specular source as 0% diffusion, and a "diffuse source" as 100% diffusion. Sharp vs. soft highlight. They use a similar scale in Poser, although they call it "highlight".

Thanks all for the clarification. Really helps to have such a source of intelligent answers for dim questions :-) BTW Mark, like your example. I've been trying to get that brushed look for months. Now I'll go give it another try. Ed PS I will soon be losing my internet connection for the summer and will not be back on the net til next fall late. Should this be my last post, I hope you all have an enjoyable and productive summer.