LightGroupMixer is a Nuke node that you can use to grade several light groups in one organized location. It also comes with the LightGroupGrade node, which allows you to easily manually select a light group and grade it.
- By default it looks for lightgroup layers that start with the prefix "LG_", you can change this constant in the light_group_mixer.py file.
- Plug your image which contains the light group layers into the LightGroupMixer node.
- Click on the "update light groups" button.