These settings control the amount, type, and quality of motion blur. Arnold can apply motion blur to cameras, objects, lights, and shaders.
Enables motion blur.
Sets an instantaneous shutter for the camera, so that the beauty and other AOVs are not motion blurred, but you still get motion vectors for the Motion Vector shader or the Motion Vector AOV.
This option specifies whether motion blur will take into account geometry deformation. This should only be enabled when objects in the scene change shape quickly enough since this option uses more memory and renders slower. Adding motion blur to hair also requires Deformation Keys. It is enabled by default.
Switch for enabling or disabling camera motion blur (enabled by default).
Switch for enabling or disabling motion blur on shader parameters (disabled by default).
The number of sub-steps used for motion blur can be set in the keys attribute within the Motion Blur settings. For situations where there is a direct movement, such as translation and rotation with constant speed, two keys are enough. However, if the object moves erratically during the exposure interval or performs any other kind of non-linear movement, you will need to increase the number of keys.
Below are examples where an increase in the number of keys is required. Notice that increasing the number of keys rounds off the corners of the spinning wheel:
The effect is more apparent when animating a deforming object along a motion path:
Specifies an Offset for the shutter’s time interval which allows you to change the motion blur trails. The Position offsets the motion blur within the image. It is a relative value that extends towards the frame.
This setting allows you to control when the camera shutter opens and closes relative to the frame being rendered.
The shutter opens at the current frame. For example, rendering frame 5 with a length of 1 would result in the times 5.0, 5.5, 6.0 being calculated.
The shutter is open during the current frame. For example, rendering frame 5 with a length of 1 would result in the times 4.5, 5.0, 5.5 being calculated.
Makes the shutter close at the current frame. For example, rendering frame 5 with a length of 1 would result in the times 4.0, 4.5, 5.0 being calculated.
Allows you to define the start and end point for the motion range.
You can use this attribute to tweak the size and length of the motion blur trails. Normally this won't be bigger than one frame unless you are looking for an exaggerated effect.
To get a 180 degrees shutter angle, you should use a length of 0.5 frames (since the exposure time will be 1/48s (assuming you are using 24 fps), which is the equivalent to 0.5 frames).
A value of 0 yields no motion blur, while larger values create longer blurred trails, simulating a faster speed. The standard value is 0.5, equivalent to a 180° shutter angle.
The shutter length is equivalent to the exposure time above.