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Transforms only have a single attribute to control how many additional motion samples 3Delight should use. These samples will be applied on the transforms and not on the objects themselves. For example, if you wish to use samples on a rotating propeller, increase Additional Samples on the transform that is responsible of the rotation and not on the propeller's geometry. Motion blur has to be enabled in the Quality render settings for this parameter to have any effect.
The following images show renders of a rotating propeller with different settings for Additional Samples.
Gallery columns 2 includeLabel transformation_mb
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