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1. Light Filters & Light Linking are currently not supported
   
   
2. "shot" based lighting features will be available in future releases.  Examples include:
   
   1. Emission Focus
   2. Light groups
   3. Manifold Next Event Estimation
      
      
3. Thin shadows are currently not implemented.
   Mesh lights, PxrCylinderLight and PxrEnvDaylight are yet to be supported.
   
   
4.  XPU does not support colour color temperature on lights yet. This means the correct colour color space won’t be applied when a temperature is converted to an RGB value

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1. XPU currently only outputs EXR or TIFF frames
   
   
2. Adaptive sampling is yet to be implemented
   
   
3. Motion blur has not been fully implemented
   
   
4. Trace Subsets have not been implemented.  This then impacts the subsurfaceSubset feature of PxrSurface
   
   
5. Only some geometric built-in AOVs are available under the same name they are available for RIS
   
   
6. Deep Output. Coming soon.
   
   
7. Multi-camera, multi-frame are is not yet supported
   
   
8. The built-in curvature calculation different is different to RIS, which results in differences in specular mollification.
   
   
9. The "weighted" option for the pixelfiltermode parameter to the Hider is not yet supported.
   
   
10. Procedurals not supported.  However, if you are using the latest XGen in Maya, you should get renders of your data.
    
    
11. Baking - either at the pattern level via PxrBakeTexture or at the renderer level to bake global illumination is not yet supported.

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