Quote - Do you have an IES scene done  already Paolo?

I don't and I should. That's gonna be something to do.

Quote - I trust in DAZ/Reality you use geometry like in 3D-Max or AGI 32 that approximates the fixture/light source, position it appropiately in the scene, and upload the IES text file for each type (group) and that represents the fixture light output?

You associate a IES file with a light. You can evem use a point light and the IES file will override everything about the nehavior of that light.

Quote - Does LuxRender automatically calculate the reflectance values of walls celiling floors, furnature and such by the materials you use? Or maybe it take the defaults (80% for walls etc) from the IES files

Nope, materials drive the rendering process. Light interracts with them.

Hope this helps.

Paolo

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