diff --git a/applications/NXmx.nxdl.xml b/applications/NXmx.nxdl.xml
index 1a7c633a9..6e5206a7d 100644
--- a/applications/NXmx.nxdl.xml
+++ b/applications/NXmx.nxdl.xml
@@ -171,12 +171,16 @@
                         single per-pixel array applied to every image (dimensions (i, j) or (i, j, k)),
                         or a per-image correction specified with an array whose slowest rank is nP (dimensions
                         (np, 1), (np, i, j) or (np, i, j, k)).
+
+                        When ommited, the scaling factor is assumed to be 1.
                 </doc>
                 </field>
                 <field name="data_offset" type="NX_NUMBER" optional="true">
                 <doc>
                         An optional offset to apply to the values in data.
 
+                        When ommited, the offset is assumed to be 0.
+
                         See :ref:`data_scaling_factor &lt;/NXmx/ENTRY/DATA/data_scaling_factor-field&gt;` for more information.
                 </doc>
                 </field>
diff --git a/base_classes/NXdata.nxdl.xml b/base_classes/NXdata.nxdl.xml
index b53c68b16..9572b309a 100644
--- a/base_classes/NXdata.nxdl.xml
+++ b/base_classes/NXdata.nxdl.xml
@@ -464,12 +464,16 @@
 				corrected values = (FIELDNAME + offset) * scaling_factor
 
 			This formula will derive the values to use in downstream applications, when necessary.
+
+			When ommited, the scaling factor is assumed to be 1.
 		</doc>
 	</field>
 	<field name="FIELDNAME_offset" type="NX_NUMBER">
 		<doc>
 			An optional offset to apply to the values in FIELDNAME (usually the signal).
 
+			When ommited, the offset is assumed to be 0.
+
 			See :ref:`FIELDNAME_scaling_factor &lt;/NXdata/FIELDNAME_scaling_factor-field&gt;` for more information.
 		</doc>
 	</field>