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Enables motion blur for the entire scene. By default, 3Delight will use produce a 2-step motion blur unless an object or transform overrides this default to something else. Refer to The Object Attributes.
Max Diffuse Depth
Sets the maximum depth a diffuse ray can have. Diffuse depth count is incremented each time a ray hits a diffuse surface.
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Sets the maximum depth a hair ray ray can have. Hair depth count is incremented each time a ray hits a surface with a Hair and Fur material applied.
Max Distance
This sets the maximum distance a ray can travel in the scene. If no objects are hit before that distance the ray will only return illumination from light sources (including environment).