diff --git a/image_analysis/IndexAndRefine.cpp b/image_analysis/IndexAndRefine.cpp
index c7259e1f..7ce56467 100644
--- a/image_analysis/IndexAndRefine.cpp
+++ b/image_analysis/IndexAndRefine.cpp
@@ -103,8 +103,10 @@ void IndexAndRefine::RefineGeometryIfNeeded(DataMessage &msg, IndexAndRefine::In
         .max_time = 0.04 // 40 ms is max allowed time for the operation
     };
 
-    if (experiment.IsRotationIndexing())
+    if (experiment.IsRotationIndexing()) {
         data.refine_beam_center = false;
+        data.refine_unit_cell = false;
+    }
 
     if (outcome.symmetry.crystal_system == gemmi::CrystalSystem::Trigonal)
         data.crystal_system = gemmi::CrystalSystem::Hexagonal;