diff --git a/src/aare/daq/daq.py b/src/aare/daq/daq.py
index 086a915c..546976a1 100644
--- a/src/aare/daq/daq.py
+++ b/src/aare/daq/daq.py
@@ -787,13 +787,13 @@ class AareDAQ:
             raise
 
 
-    def __auto_center(self, grid: RasterGridRequest) -> CompletedRasterGrid | None:
+    def __auto_center(self, request: RasterGridRequest) -> CompletedRasterGrid | None:
         sample = self.sample
 
         if sample is None:
             raise Exception("Sample must be mounted to auto center")
 
-        old_prefix = grid.file_prefix
+        old_prefix = request.file_prefix
         geom = self.sample_geometry
         r = self.__ml_bounding_box(sample.db_id, f"ml_{geom.omega_deg:.2f}deg")
 
@@ -804,6 +804,7 @@ class AareDAQ:
 
         if r is not None:
             geom = self.sample_geometry
+            grid = copy.deepcopy(request)
             grid.smargon_top_left = r.smargon_top_left
             grid.grid_size_mm = r.grid_size_mm
             grid.n_x = r.n_x