diff --git a/src/spatialgeometry/geom/Shape.py b/src/spatialgeometry/geom/Shape.py
index 328cdda..2237fce 100644
--- a/src/spatialgeometry/geom/Shape.py
+++ b/src/spatialgeometry/geom/Shape.py
@@ -374,7 +374,7 @@ def opacity(self) -> float:
         return self._color[3]
 
     @opacity.setter
-    @update
+    @mark_changed
     def opacity(self, value: float) -> None:
         if value > 1.0:
             value /= 255