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• The first thing you need to do is select ACES1.2 from the OpenColorIO parameter in the Features tab within the Render Settings.  
  
  
• If IT is already open from a previous Linear project, you will now have to close IT as IT needs to re-start within the new ACES colorspace
  
  
• When working with textures, RenderMan will now handle all the conversion needed to get your textures into the ACES colorspace.
   
  For instance, if you insert a Diffuse or Albedo color linear sRGB map into the Diffuse parameter of a PxrSurface, the Texture Manager will not only convert it to RenderMan's preferred file format (.tex) but will also automatically handle the color conversion to the ACES colorspace at the same time. 
  
  
• This is also the same for when you insert a an HDRI map into the PxrDomeLight or when working with Normal or Bump maps.  Based off on the rules, the Texture Manager handles all the conversion conversions for you.
  
  
• You will now also be working with ACES calibrated light temperatures and intensities.
  
  
• Whether you render within IT, Maya's viewport, or Maya's RenderView, you will now be rendering within the ACES colorspace.
  
  

Converting an older Linear Maya project to ACES

If you wish to pickup pick up an older Maya project and re-render it using ACES, here are some guidelines.

• With your project loaded in Maya, select the ACES1.2 config from the OpenColorIO parameter in the Features tab within the Render Settings. 
  
  
• Open RenderMan's Texture Manager from either the RenderMan shelf or menu and next to the Parse Scene button, you will now see a new Refresh all Textures and Re-Parse the scene icon.  Once pressed, the Texture Manager will now go ahead and convert all your color maps (diffuse, albedo, etc) into the ACES color space.
  
  
• You might now need to re-adjust your light intensities and temperatures, along with any Dome Light settings to re-compensate for the adjustment of moving to the ACES color space.

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