Vector Motion Blur
From left to right: Phase values of 100%, 0% and -100%.The Phase value defines the position of the blur. The following Phase values should serve as a reference:
Density set to a low value (left) and high value (right).The Density value defines the coverage of the blur in the image.
Samples set to a low value (left) and high value (right).Samples allow you to set the resolution or smoothness of the blur. Low values result in a grainy look, while more samples increase both the quality and the render time.
Sample Radius set to a low value (left) and high value (right).The higher the Sample Radius, the less crisp the blur will look.
Weighted Trails disabled (top) and enabled (bottom).The Weighted Trails option uses a different algorithm that allows the trails to fade out towards the end, resulting in a realistic trail.
Enable this option to also blur deformer objects such as FFDs.