Quote - - 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.

* - 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.*

 
If high render settings is the 'solution' you may as well use lux. The idea here is to see how far you can get with fast renders under ordinary settings. It's in the first post: "Yes they aren't particularly high or optimized but they render fast (about 30-40s) We could pump them up to get rid of some of these artifacts (but not all) or disable IC altogether and do a really long render... but is there a better way ?"

Quote - - 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.)

'Scattering artifacts' are a direct result of people trying to push more light into dark scenes with super bright sources (500%, 700% etc) The problem is CG lighting doesn't always work like real world lighting, not in Poser anyway, so all you get is blown out areas near the light and dark areas everywhere else. There are better ways to do the same thing.

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

Not at all :)

Quote - Re glowing couch back against wall - IDL reflection is wrong in Poser. Use D3D dialog to decrease IDL intensity to .65.

I didn't know that. Could you elaborate on what the problem is ?