Object motion blur applies a blur effect to make fast-moving objects appear to move more smoothly in animations. It is a form of "temporal antialiasing."
Left: Object motion blur. Right: Object motion blur with dithering.
Applying object motion blur is a two-step process:
You cannot apply both image motion blur and object motion blur to the same object in the same rendering.
Object motion blur works by rendering multiple copies of the object in between frames and then rendering them together. It is not affected by camera movement.