So I set up a very simple scene with a backdrop and ball prop, surrounded by two bb environment spheres with HDRs attached (note - one sphere supplies ambient light, the second (slightly smaller with shadowcasting and light emmitting disabled) is for reflections.

The first render uses typical settings:

Ball & backdrop - Diff 0.8, (ball has reflection) EnvSphere set to Ambient=1

Second render uses the revelation bb has just dropped on us:

Ball & backdrop - Diff 0.15 (ball has same reflection) EnvSphere 1 set to Ambient=8

 

What a difference. Even with just the EnvSphere as an emitter, in the first render too much light is reflecting from the diffuse material, interfering with the added reflection.

 

PoserPro2014(Sr4), Win7 x64, display units set to inches.

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