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To output the multichannel EXR for the denoising workflow:

• ROP node > Displays Images > Display Device >  OpenEXR (This is for exporting final renders, for previewing with the Nvidia AI Denoiser in "it" you can leave the Display Device as "it")
• Select Single Frame or Cross Frame in ROP's Display Images Tab at the bottom.  This will auto-select the appropriate AOVs (only if you followed the step above)

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