Is there a way to Pre Filter LDAP on the connection

Is there a way to set a filter during the connection phase or is it just preset to bring in everything with the Base DN. I am able to connect see the schema but if I try to browse anything I time out. I know my service account is limited to 2000 results and I'm dealing with a LDAP environment with over 3 million objects but what I need to actually see can be filtered to 500 results.