diff --git a/src/xfel_calibrate/calibrate.py b/src/xfel_calibrate/calibrate.py
index 2a9b30e1bbdead3da0e10509b3928597de1de8ce..6173d0585370e88fe0e321caa055a782176450b8 100755
--- a/src/xfel_calibrate/calibrate.py
+++ b/src/xfel_calibrate/calibrate.py
@@ -1172,7 +1172,7 @@ def run():
     if args['prepare_only']:
         # FIXME: Clean up where this file goes when.
         # When the jobs run, it is copied by finalize.py
-        metadata.save_copy(run_tmp_path)
+        metadata.save_copy(Path(run_tmp_path))
 
         print("Files prepared, not executing now (--prepare-only option).")
         print("To execute the notebooks, run:")