BB and I discussed all this some time ago.

 - raytrace bounces is too low, in your render settings rays are cut off after 5 bounces. Nature uses infinite bounces. Pump up the volume. Use the D3D Render Firefly script to discriminate between reflection bounces and IDL bounces.

 - the scene is not closed, but open at one side. This is a huge lighting leak. Increasing the bouncing will hardly help when you don't stop the leak. Just a far-away dome won't do, so build up the missing wall.

 - irradiance caching is too low, only 30% of the area is re-emitting light from calculations, the rest is guessed. Decent values for high end quality renders should be no less than 80, lower values are for testing purposes. Values over 90 are overkill and add more to the render time than to the quality. So does switching off the cashing completely.

 - IDL quality is too low. This parameter is to be used to limit the artifacts when you want decent results with relatively low irradiance caching settings. Having them both at a low value is asking for reduced quality results. It's in the manual.

 - and in addition: do not put direct lights which an (inverse) quadratic falloff too close to any surface, or you will face scattering artifacts (since the falloff formula will make the lighting levels too high close to the lights, and IDL makes the surfaces reflect that.)

 - plus: when the scene hosts a few small IDL light sources only you run the risk of splotchy shadows unless all rendering options (and render time!) are pumped up. Just do as photographers: use large softboxes instead. This is my general note: Poser is a virtual photo studio, so you have to light scenes as a photographer would do.

Hope I didn't spoil the fun of this thread too much. Sorry for that.

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Usually I'm wrong. But to be effective and efficient, I don't need to be correct or accurate.

visit www.aRtBeeWeb.nl (works) or Missing Manuals (tutorials & reviews) - both need an update though