diff --git a/eos/options.py b/eos/options.py
index 10db230..7e9bd46 100644
--- a/eos/options.py
+++ b/eos/options.py
@@ -433,8 +433,8 @@ class ReflectivityReductionConfig(ArgParsable):
             metadata={
                 'group': 'input data',
                 'help': 'apply convolution on lambda axes to smooth the normalization data, useful for low statistics'})
-    scale: List[float] = field(
-            default_factory=lambda: [],
+    scale: Optional[List[float]] = field(
+            default=None,
             metadata={
                 'short': 's',
                 'group': 'data manicure',
diff --git a/eos/reduction_reflectivity.py b/eos/reduction_reflectivity.py
index 413ffb6..eb49f78 100644
--- a/eos/reduction_reflectivity.py
+++ b/eos/reduction_reflectivity.py
@@ -310,12 +310,12 @@ class ReflectivityReduction:
             logging.info(f'      {ti:<4d}  {time:6.0f}  {self.monitor:7.2f} {MONITOR_UNITS[self.config.experiment.monitorType]}')
 
             proj: LZProjection = self.project_on_lz(slice)
-            try:
-                scale = self.config.reduction.scale[i]
-            except IndexError:
-                scale = self.config.reduction.scale[-1]
-                # TODO: causes error if no '-s' argumnet is given
-            proj.scale(scale)
+            if not self.config.reduction.is_default('scale'):
+                try:
+                    scale = self.config.reduction.scale[i]
+                except IndexError:
+                    scale = self.config.reduction.scale[-1]
+                proj.scale(scale)
 
             # projection on qz-grid
             result = proj.project_on_qz()