HOWTO: Reduce Motion Blur Calculations
  
PSS ID Number: Q184917
Article last modified on 04-30-1998
 
IRIX:3.7,3.71; WINNT:3.7,3.71
 
IRIX winnt
 

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The information in this article applies to:
 
 - SOFTIMAGE 3D for IRIX, versions 3.7, 3.71
 - SOFTIMAGE 3D for Windows NT, versions 3.7, 3.71
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SUMMARY
=======
 
This article offers a method for reducing motion blur calculations.
 
MORE INFORMATION
================
 
To reduce motion blur calculations when rendering with mental ray, set the
-time_contrast R G B values to adjust the granularity of time oversampling.
The R G B values (red, green, and blue) can be set between 0 (zero) and 1,
with the default at 0.1 0.1 0.1.
 
Using a value of 0.99 0.99 0.99, the blur produces a noisy, grainy motion
blur. Values between 0.1 0.1 0.1 and 0.5 0.5 0.5 increase render speed,
while producing an acceptable blur.
 
Setting the -time_contrast to 0.5 0.5 0.5 on Windows NT
=======================================================
 
You can use one of the following two methods:
 
Option A
--------
 
Edit Setenv.bat, [this sets up all the SOFTIMAGE 3D (SI3D) environment
variables)], then modify the SI_MI_TRACER value to the following (enter
this on one line):
 
   set %SI_MI_TRACER=%SI_LOCATION%\mental_ray\bin\ray.exe -time_contrast
   0.5 0.5 0.5
 
Option B
--------
 
To render an .mi file (for example, Out.mi), enter the following at the
SI3D command prompt:
 
   ray.exe -time_contrast 0.5 0.5 0.5 out.mi
 
Setting the -time_contrast to 0.5 0.5 0.5 on IRIX
=================================================
 
You can use one of the following two methods:
 
Option A
--------
 
Edit your .softimage file (this sets up all the SI3D environment
variables), then modify the SI_MI_TRACER value to the following (enter this
on one line):
 
   setenv SI_MI_TRACER $SI_LOCATION/mental_ray/bin/ray.irix5
   -time_contrast 0.5 0.5 0.5
 
Option B
--------
 
To render an .mi file (for example, Out.mi), enter the following on the
command line:
 
   ray.irix5 -time_contrast 0.5 0.5 0.5 out.mi
 
REFERENCES
==========
 
If you have any questions concerning the information contained in this
article, contact support@softimage.com by e-mail.
 
Additional query words: si si3d si3dren si3dmr
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Keywords          : si si3d si3dmr si3dren
Version           : IRIX:3.7,3.71; WINNT:3.7,3.71
Platform          : IRIX winnt
Issue type        : kbhowto
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Copyright Microsoft Corporation 1998.