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For now, a separate OpenEXR is required to be output for each plugin, separate from your denoise or beauty EXRs. You can create a sequence by using the correct token, example: cryptomatte.${F4}<f4>.exr creates a rendered sequence with a padding of 4 spaces, cryptomatte.0001.exr

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Tell Cryptomatte you want to use: identifier:lpegroup

Or add the "Identifier Name" to the shape(s) from the RenderMan Attributes > Add > RenderMan

  Tell Cryptomatte you want to use:  identifier:name

Lastly, for groups (assigning to transform nodes) you can create your own user ID using "Transform Begin MEL" to the transform from the RenderMan Attribute menu. In the Cryptomatte Attribute field you would use the below example of "idlayers", this particular transform would write to the "fg" or foreground set of IDs.

RiAttribute "user" "string idlayers" "fg";

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