diff --git a/common/GoniometerAxis.cpp b/common/GoniometerAxis.cpp
index 09467618..b88d8e51 100644
--- a/common/GoniometerAxis.cpp
+++ b/common/GoniometerAxis.cpp
@@ -120,9 +120,7 @@ std::vector<double> GoniometerAxis::GetAngleContainerEnd(int64_t max_image_numbe
     return angle_container;
 }
 
-RotMatrix GoniometerAxis::GetTransformation(int64_t image_number) const {
-    // Transformation goes back from rotated to "start"
-    auto angle_deg = GetAngle_deg(image_number);
+RotMatrix GoniometerAxis::GetTransformationAngle(float angle_deg) const {
     auto angle_rad = angle_deg / 180.0f * static_cast<float>(M_PI);
     return {angle_rad, axis};
-}
+}
\ No newline at end of file
diff --git a/common/GoniometerAxis.h b/common/GoniometerAxis.h
index 9d19abeb..f644a40f 100644
--- a/common/GoniometerAxis.h
+++ b/common/GoniometerAxis.h
@@ -44,7 +44,7 @@ public:
 
     [[nodiscard]] std::vector<double> GetAxisVector() const;
 
-    [[nodiscard]] RotMatrix GetTransformation(int64_t image_number) const;
+    [[nodiscard]] RotMatrix GetTransformationAngle(float angle_deg) const;
 };
 
 
diff --git a/image_analysis/IndexAndRefine.cpp b/image_analysis/IndexAndRefine.cpp
index 1585685e..891c9e17 100644
--- a/image_analysis/IndexAndRefine.cpp
+++ b/image_analysis/IndexAndRefine.cpp
@@ -29,8 +29,10 @@ IndexAndRefine::IndexingOutcome IndexAndRefine::DetermineLatticeAndSymmetry(Data
 
             // get rotated lattice
             auto gon = experiment.GetGoniometer();
-            if (gon)
-                outcome.lattice_candidate = result->lattice.Multiply(gon->GetTransformation(-msg.number));
+            if (gon) {
+                const float angle_deg = gon->GetAngle_deg(msg.number) + gon->GetWedge_deg() / 2.0f;
+                outcome.lattice_candidate = result->lattice.Multiply(gon->GetTransformationAngle(-angle_deg));
+            }
 
             outcome.experiment.BeamX_pxl(result->geom.GetBeamX_pxl())
                                   .BeamY_pxl(result->geom.GetBeamY_pxl())
diff --git a/image_analysis/RotationIndexer.cpp b/image_analysis/RotationIndexer.cpp
index f3ff9372..dc2c1254 100644
--- a/image_analysis/RotationIndexer.cpp
+++ b/image_analysis/RotationIndexer.cpp
@@ -114,7 +114,8 @@ std::optional<RotationIndexerResult> RotationIndexer::ProcessImage(int64_t image
     if (!axis_)
         return {};
 
-    const auto rot = axis_->GetTransformation(image);
+    const float angle_deg = axis_->GetAngle_deg(image) + axis_->GetWedge_deg() / 2.0f;
+    const auto rot = axis_->GetTransformationAngle(angle_deg);
 
     if (!indexing_tried && image >= last_accumulated_image + image_stride) {
         v_.reserve(v_.size() + spots.size());
diff --git a/image_analysis/geom_refinement/XtalOptimizer.cpp b/image_analysis/geom_refinement/XtalOptimizer.cpp
index a3e6ac39..f1e775df 100644
--- a/image_analysis/geom_refinement/XtalOptimizer.cpp
+++ b/image_analysis/geom_refinement/XtalOptimizer.cpp
@@ -429,7 +429,8 @@ bool XtalOptimizerInternal(XtalOptimizerData &data,
             Coord recip = data.geom.DetectorToRecip(pt.x, pt.y);
 
             if (data.axis) {
-                auto rot = data.axis->GetTransformation(pt.image);
+                const float angle_deg = data.axis->GetAngle_deg(pt.image) + data.axis->GetWedge_deg() / 2.0f;
+                auto rot = data.axis->GetTransformationAngle(angle_deg);
                 recip = rot * recip;
 
                 Eigen::Matrix3d Rg;
diff --git a/tests/RotationIndexerTest.cpp b/tests/RotationIndexerTest.cpp
index 27d2be44..87f0d7b7 100644
--- a/tests/RotationIndexerTest.cpp
+++ b/tests/RotationIndexerTest.cpp
@@ -53,7 +53,8 @@ TEST_CASE("RotationIndexer") {
     for (int img = 0; img < 50; ++img) {
         std::vector<SpotToSave> spots;
         // For a rotated image, per-image lattice is obtained as Multiply(rot.transpose())
-        const RotMatrix rot = axis.GetTransformation(img);
+        const float angle_deg = axis.GetAngle_deg(img) + axis.GetWedge_deg() / 2.0f;
+        const RotMatrix rot = axis.GetTransformationAngle(angle_deg);
         const CrystalLattice latt_img = latt_base.Multiply(rot.transpose());
 
         const auto n = prediction.Calc(exp_i, latt_img, prediction_settings);
diff --git a/tests/XtalOptimizerTest.cpp b/tests/XtalOptimizerTest.cpp
index 031716c8..8503c8b0 100644
--- a/tests/XtalOptimizerTest.cpp
+++ b/tests/XtalOptimizerTest.cpp
@@ -576,7 +576,8 @@ TEST_CASE("XtalOptimizer_rotation") {
     // Predict reflections for images at 0-30 deg.
     for (int img = 0; img < 10; ++img) {
         // For a rotated image, per-image lattice is obtained as Multiply(rot.transpose())
-        const RotMatrix rot = axis.GetTransformation(img);
+        const float angle_deg = axis.GetAngle_deg(img) + axis.GetWedge_deg() / 2.0f;
+        const RotMatrix rot = axis.GetTransformationAngle(angle_deg);
         const CrystalLattice latt_img = latt_base.Multiply(rot.transpose());
 
         const auto n = prediction.Calc(exp_i, latt_img, prediction_settings);