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102 Chapter 17: Rendering
Inter face
Motion Blur group
Tip: mental ray motion blur is not recommended
for use with particle systems, as this can increase
rendering time considerably. Use a
Particle MBlur
map (page 2–1486)
instead.
Note: Motion blur with the mental ray renderer
does not always follow curving trajectories.
Increasing the value of M otion Segments can help,
but this works better for rotary motion than for
traveling motion.
TheToggle(lower-right)quadoftherendering
quad menu (CTRL+ALT+r ight-click) has a
Motion Blur toggle that lets you turn on motion
blurforselectedobjects.YoucanturnonMotion
Blur for lights and cameras: moving lights and
cameras can generate motion blur when rendered
with mental ray.
Enable—When on, the mental ray renderer
calculates
motion blur (page 3–88) . D efault=off.
Blur All Objects—Applies motion blur to all
objects, regardless of their object property sett ing.
Default=on.
Shutter Duration (frames)—Simulates the shutter
speed of a c amera. At 0.0, there is no motion
blurring. The greater the Shutter Dur ation value,
the greater the blurring. Default=0.5.
Shutter Offset (frames)—Sets the beginning
of the motion-blur effect relative to the current
fra me. The default value, 0.0, centers the blurring
around the current frame for a photorealistic
effect. Default=0.0.
Motion Segments—Sets the nu mber of segments
for calculating motion blur. This control is for
animations. If motion blur appears to be tangential
to the actual motion of an object, increase the
Motion Segments va lue. Larger values result in
more accurate motion blur, at a cost of rendering
time. Default=1.
Contours group
Thesecontrolsenablecontours,andletyouuse
shaders to adjust the results of a contour shader.
Youassigntheprimarycontourshadertothe
Contour component of the
mental ray Connection
rollout (page 2–1305)
or a mental ray material (see
Advanced Shaders Rollout (mental ray Material)
(page 2–1388)
).
Note: Contour shading does not work with
distributed bucket rendering.
Enable—When on enables rendering of contours.
Default=off.
Click a button to change a shader assig nment for
adjusting contours. A default is already assigned to
the three components, as the button labels indicate.
Contour Contras t—The contour contrast
comp onent can be assigned the following shader: