Motion Blur
By default, Trapcode Horizon uses the After Effects comp settings for Motion Blur. To determine the amount of motion blur, set the shutter angle and phase in the Composition > Composition Settings >Advanced settings within After Effects.
Motion Blur can be disabled by selecting Off in the Motion Blur pop-up. This overrides the layer Motion Blur switch, so that if the layer's motion blur switch is on and the Motion Blur pop-up is set to off, then no motion blur will be rendered by the plug-in.
Levels
Select how many levels or time samples of motion blur to render. More levels or samples means greater smoothness, but will take longer to render. You may need to increase the Levels value to 16 or 32 to create a smoother blur if the camera is moving rapidly in the scene.