I can not find a way to find the project halftone/underlay settings using dynamo. This setting is located under ‘Manage tab’ > ‘Additional Settings’ > ‘Halftone / Underlay’. I have not found a node for this nor a way to access it through a collector using python.
@martin.scholl I believe the only API documentation related to the Halftone / Underlay settings is its Postable Command, which in Python would merely mimic pressing the button in Revit itself and would still require UI action by the user.
It does not appear that the API provides access to the actual values within this setting, however.