Going back through a whole load of posts here (prompted by pumeco's announcement of his 'PRO-RENDER'), it occurred to me that I haven't actually specified what it is that I've been going on about with True Ambience. I've presented everything obliquely, but not actually spelled it out. I apologise for this oversight, but it's not as if I've been selfishly making amazing pics with 'my' knowledge, or anything - I just didn't get organised. Anyway, here goes. What I found was that it was best to turn the concept of Bryce 'ambience' completely on its head. Under the normal render settings, a Bryce material that has some ambience will appear to be lit by itself - it is illuminated whether there is an external light source or not. Taken to the maximum setting, it will appear to glow (with no effect on its surroundings). I always hated the unrealistic appearance of ambient materials, and avoided them at all costs - preferring to use multiple lights to provide 'fill'. However, messing about in the depths of the True Ambience feature eventually led to a realisation. The True Ambience setting can treat ambient materials in a completely different way to normal. I reckon the best way to think of how materials interact in the way I use True Ambience is like this: - Diffuse materials act as diffuse 'reflectors' of light. - Ambient materials act initially as 'receivers' of this diffuse light, and subsequently as both 'reflectors' and 'receivers'. The absolute key to how this works (bizarrely enough) is to enable ambience in all individual materials but disable all ambience overall by way of the sky settings (set 'ambient color' to black under the 'shadows' window). In a normal render this will result in no ambience. Under True Ambience, this will result in, effectively, radiosity. Under this variation of True Ambience, a light shone onto a diffuse material will illuminate that material as normal. However, that diffuse material will now also act as a diffuse illuminator upon the ambient channel of any material. It will act upon those ambient channels whilst taking into account any obstruction by objects. It will act with appropriate light falloff. Any ambient channel thus lit will now act similarly upon any ambient channel, again taking into account obstruction and light falloff. And so on. This is as close as Bryce gets to the automatic 'bouncing' of diffuse light - and it's bloody amazing. For realism, the ambient channel of materials should be set to the same colour as the diffuse channel; and (as a starting point) the ambient channel should be set at 60 (diffuse 100). The sky dome also acts as a diffuse illuminator. Unfortunately, this method is flawed for reasons I've mentioned previously. Mesh objects do not smooth under 'ambient' light. Some primitives (the cube!) do act consistently under 'ambient' light (one side brighter than the other; light 'leaking'). The result of Bryce booleans fails to respond to 'ambient' light properly. Transparency doesn't work properly under 'ambient' light. These problems are a real shame, because without them this would amount to a render feature for fantastic realism. Hopefully pumeco's 'PRO-RENDER' will live up to the hype and overcome these limitations, and we'll all be knocking out photorealism with no downsides. This should give you something to chew on in the meantime. (BTW, it's gone 2am here, and I've probably forgotten something important (no proofing!). I'll look in tomorrow and answer any questions)