Overview
The Motion Blur group of attributes affects how motion blur is rendered for various scene components. Note that motion blur can also be controlled per object in the Motion Blur group of a Geometry Attributes Node, as described inMotion Blur.
The frame exposure time is defined by the render camera's Shutter Angle attribute, which is inside the Special Effectsgroup of a standard Maya Camera. See Scene Elements for how to select a render camera.
The various "Samples" attributes have a default value of 2, meaning that the movement is sampled at the beginning and at the end of the frame exposure. This is fine for linear movements. Increase the relevant "Samples" attribute if the motion path of the camera or objects is far from linear (like a turning propeller for example). Higher sample values imply longer motion blur computation.
In order to be correctly motion blurred, the objects must have a properly defined position or deformation in between frames. Furthermore, the scene must be set up to allow arbitrary changes of the current time. Generally this means that all dynamics, nDynamics and fluid simulation must have a disk cache, because the scene will not necessarily be played back in the order required for the simulation to operate correctly in an incremental manner.
Note that due to the way they are exported, anything involving particle systems, nParticle systems and particle instancers will require Enable Deformation Blur to be turned on to render with proper motion blur.
The Motion Blur group
Enable Camera Blur
When this toggle is on, the movement of the camera is taken into account when computing the motion blur. By default this toggle is off.
Enable Transformation Motion Blur
When this toggle is on, objects that have animated geometric transformation (translation, rotation or scale) will be blurred. By default, this toggle is off.
Enable Deformation Motion Blur
When this toggle is on, objects whose geometry is deforming (such as cloth simulation geometry or animated fur) will be blurred. By default, this toggle is off. Deformation motion blur should be enabled only when necessary since it has a higher memory footprint.
Camera Blur Samples
This attribute specifies the number of times the position and orientation of the camera is sampled during the time interval that the shutter is opened. The default number of camera samples is 2.
Transformation Samples
This attribute specifies the number of times the transformation of the object is sampled during the time interval that the shutter is opened. The default number of transformation samples is 2.
Deformation Samples
Specifies the number of times the geometry of the object is sampled for motion blur during the time interval that the shutter is opened. The default number of deformation samples is 2.
Motion Blur Position
...