Ivy! this is great. Iray really makes beautiful work of shadows and reflections, as expected of a path tracing engine. How long did this take per frame on average? You mentioned 3 days with two GTX 1080tis? That seems like a really long time for 1 minute of animation, even though I see there are plenty of reflections and GI going on here. I would have expected those GPU's to really crank out the frames much faster, considering the power of those cards. I wonder if there's a bottleneck going on with your CPU, because I think Iray uses both GPU and CPU? Or did you have it just using the GPU here? Also, were your 1080's set up in SLI or as seperate cards? I've heard reports of SLI actually impacting performance negatively compared to running renders with seperate GPUs. I don't have Daz Studio so I can't test my RTX 2070 with it for a comparison, but have you tried out the Eevee render engine in Blender yet? It's not a path tracer like Cycles or Iray, but the quality you can get from it for animation is very close to what you could get from a real path tracing engine, and your 1080's would make short work of frames in there.

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