Maybe little off subject but I found last night that when rendering a scene with clouds using a sphere with cloud materials that I was getting black clouds using ultra setting. Could see white clouds in my preview render. I then found in render options where you have to check The generate under G-Buffer and then click on the options and check both Forcerendering of occluded objects and Generate all anti-aliasing layers. After doing that my scene rendered in ultra like my preview view. Hope this might help someone in the future that might have this problem. :o)

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