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You can command-click to see inside these macros and change settings if necessary. On the RenderOutputDefine node, make sure asrgba is set off, and that the type is set to raw to avoid any post processing. NOTE for Eugene - I think that the denoiser requires the name to be SOMETHING.FRAMENUMBER.exr, but I haven't confirmed that.-processing.

Step 3:

Set pixelfiltermode to importance if you changed it from the default. This is done in PrmanGlobalStatements.

If your pipeline does not support multichannel EXR, you can use $RMANTREE/bin/exrmerge to combine the AOVs into a multichannel EXR. Then use this merged multichannel EXR for the denoise utility.
Note that each AOV's type should be set to "raw" because this preserves the channel name in the EXR which the denoise utility will look for. Combined EXR using Katana's RenderOutputDefine's merge will not work with the denoise utility.

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