diff --git a/common/DiffractionExperiment.cpp b/common/DiffractionExperiment.cpp
index c0757122..0bc1f0d7 100644
--- a/common/DiffractionExperiment.cpp
+++ b/common/DiffractionExperiment.cpp
@@ -78,12 +78,18 @@ DiffractionExperiment::DiffractionExperiment(const DetectorGeometry& geom) {
     internal.set_storage_cells(1);
     internal.set_storage_cell_start(15);
 
-    *internal.mutable_conv_geometry() = geom;
-
+    Geometry(geom);
     Mode(DetectorMode::Conversion);
 }
 
 // setter functions
+DiffractionExperiment &DiffractionExperiment::Geometry(const DetectorGeometry &input) {
+    check_min("Number of modules", input.GetModulesNum(), 1);
+    check_max("Number of modules", input.GetModulesNum(), 64); // if operating > 32M, would need to check the code anyway
+
+    *internal.mutable_conv_geometry() = input;
+    return *this;
+}
 
 DiffractionExperiment &DiffractionExperiment::Mode(DetectorMode input) {
     switch (input) {
diff --git a/common/DiffractionExperiment.h b/common/DiffractionExperiment.h
index 6a8277cd..8400ac10 100644
--- a/common/DiffractionExperiment.h
+++ b/common/DiffractionExperiment.h
@@ -36,6 +36,7 @@ public:
     explicit DiffractionExperiment(const JFJochProtoBuf::JungfraujochSettings &settings);
 
     // Methods below can be chained together
+    DiffractionExperiment& Geometry(const DetectorGeometry &input);
     DiffractionExperiment& Mode(DetectorMode input);
     DiffractionExperiment& DataStreams(int64_t input);