diff --git a/semeio/workflows/localisation/local_script_lib.py b/semeio/workflows/localisation/local_script_lib.py
index 2c4a2aab2..1c43e5e70 100644
--- a/semeio/workflows/localisation/local_script_lib.py
+++ b/semeio/workflows/localisation/local_script_lib.py
@@ -26,6 +26,10 @@
     debug_print,
 )
 
+try:
+    from typing import Self
+except ImportError:
+    from typing_extensions import Self
 
 @dataclass
 class Parameter:
@@ -262,7 +266,7 @@ def write_qc_parameter_surface(
         reference_surface_file: str,
         param_for_surface: object,
         log_level=LogLevel.OFF,
-    ):
+    )->None:
         # pylint: disable=too-many-arguments
 
         if param_for_surface is None or surface_scale is None:
@@ -463,7 +467,7 @@ def apply_decay(
     perp_range: float,
     azimuth: float,
     use_cutoff: bool = False,
-    tapering_range: float = None,
+    tapering_range: float = 1.5,
     calculate_qc_parameter: bool = False,
 ):
     # pylint: disable=too-many-arguments,too-many-locals