I have a custom web service which is depolyed under the 15/ISAPI directory.  I call it via HTTP Web Service from SP2013 Designer Workflows.  Inside the C# code I log using below and I want verbose info.

SPDiagnosticsCategory category = new SPDiagnosticsCategory("MyCustomServiceCategory",
  TraceSeverity.Verbose,
  EventSeverity.Information);
  SPDiagnosticsService diagSvc = SPDiagnosticsService.Local;

catch ...

    category.EventSeverity = EventSeverity.Error;
   diagSvc.WriteTrace(0, category, TraceSeverity.Verbose, trace);

sometime I just write information messages also using the default.
   diagSvc.WriteTrace(0, category, TraceSeverity.Verbose, trace);

In Central Admin there are a lot of categories for monitoring.  I don not want them all verbose.  Most should stay the default. If I leave everything default Info/Medium.  I get no logs messages from the service.

I can't correlate which one(s) match up to the log messages I'm writing in this webservice so I can make it verbose.

For Instance:

Sharepoint Foundation

      General, Workflow Services.... which one?

So far I've been setting everything under Sharepoint Foundation and Sharepoint Server to verbose/verbose but that can't continue.

Thanks