how do i exclusivly log requests of phpscripts with mod-security?

Question

how do i only log (audit) requests (get and post parameters) to php scripts with modsecurity?

i dont want the static content to fill up my logs

Right now i m having everything logged.

i tried RelevantOnly but then nothing gets logged. I found this could be used in version 1.9 for php-only-logging but where did it go in 2.5? Here is my configfile:

<IfModule mod_security2.c>
 #Basic configuration options
      SecRuleEngine DetectionOnly
      SecRequestBodyAccess On
      SecResponseBodyAccess Off
#SecFilterScanPOST On
      # Handling of file uploads
      # TODO Choose a folder private to Apache.
      # SecUploadDir /opt/apache-frontend/tmp/
      SecUploadKeepFiles Off

      # Debug log
      SecDebugLog /var/log/apache2/modsec_debug.log
      SecDebugLogLevel 3

      # Serial audit log
      SecAuditEngine On
# RelevantOnly
     # SecAuditLogRelevantStatus "^(?:5|4(?!04))"
      SecAuditLogParts ABIFHZ
      SecAuditLogType Serial
      SecAuditLog /var/log/apache2/modsec_audit.log
</IfModule>