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Equiangular weight
he probability of equiangular sampling being used instead of density sampling. Equiangular sampling improves the convergence of volumes close to light sources, while density sampling can be a better technique when dealing with volumes with dense or highly varying density. The default value of 0.5 means both techniques will be used equally and combined with multiple-importance sampling.

If the volumes are dense and far away from light sources then decreasing the equiangular weight may result in better convergence.
This control has no effect on aggregate volumes.

Min samples
Controls the minimum number of samples to take inside the volume per ray. Only used when single scattering. The default is 4.
This control has no effect on aggregate volumes

Max samples
Controls the maximum number of samples to take inside the volume per ray. The default is 4.
This control has no effect on aggregate volumes.

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