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• macOS 11 or 12 (Big Sur or Monterey): The installer can download the packages from Pixar, but can't run them to get them unpacked.  You must manually double-click on the .pkg files that the installer leaves in the Downloads folder.  RMAN-18802
• macOS: During installation, you will see the RenderMan 24 License Server instead of the RenderMan 25 License Server.  This is expected.  RMAN-20602

Denoiser

• macOS/Apple Silicon: The denoiser is not supported on Apple Silicon, even with Rosetta.  RMAN-20408
• If your image has NaNs, the denoiser will fail on macOS and Windows.
• The denoiser can only denoise images from XPU on Linux.  For Linux, Windows, and macOS Intel machines, the denoiser works for RIS.
• XPU is not ouputting AOVs with motion vectors, which will reduce the cross-frame denoising quality.

RIS and XPU

• Color Management: Although we have upgraded to the VFX Reference Platform 2021, there are still color management limitations:
  • IT does not support OCIO 2.0 configs yet.  RMAN-19921
• MaterialX: Material layering is not supported.  RMAN-20365

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