Hi Frank,
I'm going to refer you to some logstash posts like;
You can also search that logstash forum for geopoint to find other posts about it.
If you're still having problems, please post another question there. Also, please include the logstash version you're using as things do change from release to release.
Apache, Apache Lucene, Apache Hadoop, Hadoop, HDFS and the yellow elephant
logo are trademarks of the
Apache Software Foundation
in the United States and/or other countries.