A big thing in Superfly is Ambient in shaders. Superfly actively checks lights, every material with ambient IS concidered to be a light. Removing Ambient from materials which aren't supposed to be glowing will make you images clean in much fewer samples.

By the way, the amount of samples you need to get a clean can vary greatly. I usually make a partial render of a part of skin to see how much samples I need.

Which graphic card do you have? I have a GTX 970. I can render images with it at roughly the same speed and I can with my 8 core 16 thread Ryzen. If you have a 16 core xeon, things may be similar for you. Try a render with the following settings:

Please take note: you need smaller buckets for CPU rendering. This will affect speed a lot.

Use a smaller resolution for that one, render for 10 Minutes or so, then cancle the render. Then do a Cuda render with this settings:

Let it run for the same time before canceling.

Then check both images closely - which one is less grainy? That's the way of rendering which is faster on your system.

After that you should check with small parts of the image in full resolution how much samples you need to get a clean image. Use skin or shaded areas. Then render tho whole image with that number of samples.

You will get lesser render times. And remember - make sure you don't have materials with unneeded Ambient. This can easily multiply the number of needed samples with three or four.

A ship in port is safe; but that is not what ships are built for.
Sail out to sea and do new things.
-"Amazing Grace" Hopper

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