8

Default Scanline R enderer Rollout 41
Sampler drop-down list—
Lets you choose which
supersampling method to apply. Default=Max 2.5
Star.
The options for a supersampling method are the
same as those that appear on t he
SuperSampling
rollout (page 2–1302)
in the Material Editor. Some
methods offer expanded options that let you better
control the quality of the supersampling and the
number of samples taken duri ng rendering.
Object Motion Blur group
You determine which objects have
object motion
blur (page 3–1075)
applied to them by setting
ObjectintheMotionBlurgroupoftheProperties
dialog for that object. Object mot ion blur blurs
the object by creating multiple "t i me-slice" images
of the object for each frame. It takes camera
movement into account. Object motion blur is
applied during the scanline rendering process.
Apply—Turnsobjectmotionbluronoroffglobally
for the entire scene. Any objects that have their
Object Motion Blur property set are rendered with
motion blur.
Durati on—D etermines how long the "virtual
shutter" is open. When this is set to 1.0, the v irtual
shutterisopenfortheentiredurationbetweenone
frameandthenext.Longervaluesproducemore
exaggerated effec ts.
The effect of changing duration.
Samples—DetermineshowmanyDuration
Subdivision copies are sampled. The maximum
setting is 32.
WhenSamplesislessthanDuration,random
sampling with in the duration occurs (which is why
there might be a slight granular look to the motion
blur). For example, if Duration Subdivision=12
and Samples=8, there are eight random samples
out of 12 possible copies w ithin each frame.
When Samples=Duration, there is no randomness
(and if both numbers are at their maximum value
(32),yougetadenseresult(whichcostsbetween
3–4 times the normal rendering time for that
specific object).
If you want to obtain a smooth blur effect, use the
maximum settings of 32/32. If you want to cut
dow n rendering time, values of 12/12 w il l give you
much smoother results than 16/12.
Because sampling happens within the duration,
theDurationvaluealwayshastobelessthanor
equal to Samples.
Duration Subdivisions—Determines how many
copies of each object are rendered within the
Durat ion.
Left: Same value for Samples and Subdivisions.
Right: Samples value is le ss than Subd ivisions.
Image Motion Blur group
You determine which objects have
image motion
blur (page 3–1049)
applied to them by setting
Image in the Motion Blur group of the Properties