diff --git a/hkl/diffract.py b/hkl/diffract.py
index 67bcb312..3911e549 100644
--- a/hkl/diffract.py
+++ b/hkl/diffract.py
@@ -168,7 +168,7 @@ class (using `calc_kw`) to instantiate a new one.
     lattice_reciprocal = Cpt(
         # fmt: off
         AttributeSignal,
-        attr="calc.sample.reciprocal",
+        attr="calc._cfg_reciprocal",
         doc="Reciprocal lattice",
         # fmt: on
     )