Filtering syslog events download using /logs URL

Hi,
I’m trying to download syslog events using the /log URL. I’m specifying since and until in the URL but can’t see/find a way to exclude one common type of event.
The exact event I want to eliminate has a description of is ‘‘Perform RealTimSync by AD agent’’. This event occurs in huge numbers and by removing it from the download I should be able to run regular downloads far faster.

Have I missed something and is there a filter I can add which will exclude just that one event?
/logs?since=$since&until=$until&filter=$filter&q=$q&sortOrder=$sortOrder&limit=$limit"

Thanks

Rob