diff --git a/CAL/CalibrationCommon/lib/datacontainers/holography_dataset.py b/CAL/CalibrationCommon/lib/datacontainers/holography_dataset.py
index 846d04809b1ce77abc202c962dfd82a0a3feaf9b..068bc682ffd0c09c5b60e596514977ae83993dbe 100644
--- a/CAL/CalibrationCommon/lib/datacontainers/holography_dataset.py
+++ b/CAL/CalibrationCommon/lib/datacontainers/holography_dataset.py
@@ -1,5 +1,4 @@
 import logging
-import math
 import h5py
 
 from lofar.calibration.common.datacontainers.holography_observation import HolographyObservation