diff --git a/config/comCam/calibrate.py b/config/comCam/calibrate.py
index 30141325..37e88ab1 100644
--- a/config/comCam/calibrate.py
+++ b/config/comCam/calibrate.py
@@ -8,6 +8,10 @@
 config.astrometry.matcher.maxOffsetPix=1500
 config.astromRefObjLoader.pixelMargin=1500
 
+# Overrides to improved astrometry matching.
+config.astrometry.doFiducialZeroPointCull = True
+config.astrometry.load(os.path.join(obsConfigDir, "fiducialZeroPoint.py"))
+
 # Loosened for early ComCam with large PSFs.
 config.photoCal.match.sourceSelection.doUnresolved = False
 
diff --git a/config/comCam/calibrateImage.py b/config/comCam/calibrateImage.py
index 4cf0872a..97d6c136 100644
--- a/config/comCam/calibrateImage.py
+++ b/config/comCam/calibrateImage.py
@@ -28,5 +28,9 @@
 config.astrometry.matcher.maxOffsetPix=1500
 config.astrometry_ref_loader.pixelMargin=1500
 
+# Overrides to improved astrometry matching.
+config.astrometry.doFiducialZeroPointCull = True
+config.astrometry.load(os.path.join(config_dir, "fiducialZeroPoint.py"))
+
 # Loosened for early ComCam with large PSFs.
 config.photometry.match.sourceSelection.doUnresolved = False