diff --git a/common/DiffractionExperiment.cpp b/common/DiffractionExperiment.cpp
index 0e6b26aa..b184f805 100644
--- a/common/DiffractionExperiment.cpp
+++ b/common/DiffractionExperiment.cpp
@@ -816,7 +816,7 @@ int64_t DiffractionExperiment::GetStorageCellNumber() const {
 }
 
 int64_t DiffractionExperiment::GetStorageCellStart() const {
-    return internal.storage_cell_start();
+    return internal.storage_cell_start() - internal.storage_cells() + 1;
 }
 
 float DiffractionExperiment::GetLowQForRadialInt_recipA() const {
diff --git a/tests/DiffractionExperimentTest.cpp b/tests/DiffractionExperimentTest.cpp
index 4c9cb2d8..abb64c8e 100644
--- a/tests/DiffractionExperimentTest.cpp
+++ b/tests/DiffractionExperimentTest.cpp
@@ -632,6 +632,7 @@ TEST_CASE("DiffractionExperiment_StorageCells","[DiffractionExperiment]") {
     REQUIRE(x.GetSummation() == 1);
     REQUIRE(x.GetImageNumPerTrigger() == 5);
     REQUIRE(x.GetNumTriggers() == num_triggers);
+    REQUIRE(x.GetStorageCellStart() == 15);
 
     REQUIRE_THROWS(x.StorageCells(5));
     REQUIRE_THROWS(x.StorageCells(0));
@@ -642,12 +643,15 @@ TEST_CASE("DiffractionExperiment_StorageCells","[DiffractionExperiment]") {
 
     REQUIRE_NOTHROW(x.StorageCells(4));
     REQUIRE(x.GetStorageCellNumber() == 4);
+    REQUIRE(x.GetStorageCellStart() == 12);
 
     REQUIRE_NOTHROW(x.StorageCells(8));
     REQUIRE(x.GetStorageCellNumber() == 8);
+    REQUIRE(x.GetStorageCellStart() == 8);
 
     x.StorageCells(16);
     REQUIRE(x.GetStorageCellNumber() == 16);
+    REQUIRE(x.GetStorageCellStart() == 0);
     REQUIRE(x.GetSummation() == 1);
     REQUIRE(x.GetImageNumPerTrigger() == x.GetStorageCellNumber());
     REQUIRE(x.GetFrameNumPerTrigger() == x.GetStorageCellNumber());