diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4772f0b..568d868 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -31,7 +31,7 @@ set(CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake" ${CMAKE_MODULE_PATH})
 
 
 # General options
-option(AARE_PYTHON_BINDINGS "Build python bindings" ON)
+option(AARE_PYTHON_BINDINGS "Build python bindings" OFF)
 option(AARE_TESTS "Build tests" OFF)
 option(AARE_BENCHMARKS "Build benchmarks" OFF)
 option(AARE_EXAMPLES "Build examples" OFF)
@@ -307,7 +307,8 @@ endif()
 
 set(PUBLICHEADERS
     include/aare/ArrayExpr.hpp
-    include/aare/ClusterFinder.hpp
+    include/aare/Cluster.hpp
+    #include/aare/ClusterFinder.hpp
     include/aare/ClusterFile.hpp
     include/aare/CtbRawFile.hpp
     include/aare/ClusterVector.hpp
@@ -328,7 +329,7 @@ set(PUBLICHEADERS
     include/aare/RawFile.hpp
     include/aare/RawMasterFile.hpp
     include/aare/RawSubFile.hpp
-    include/aare/VarClusterFinder.hpp
+    #include/aare/VarClusterFinder.hpp
     include/aare/utils/task.hpp
 
 )
@@ -336,7 +337,7 @@ set(PUBLICHEADERS
 
 set(SourceFiles
     ${CMAKE_CURRENT_SOURCE_DIR}/src/CtbRawFile.cpp
-    ${CMAKE_CURRENT_SOURCE_DIR}/src/ClusterFile.cpp
+    #${CMAKE_CURRENT_SOURCE_DIR}/src/ClusterFile.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/defs.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/Dtype.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/decode.cpp
@@ -394,8 +395,9 @@ if(AARE_TESTS)
             ${CMAKE_CURRENT_SOURCE_DIR}/src/RawMasterFile.test.cpp
             ${CMAKE_CURRENT_SOURCE_DIR}/src/NDArray.test.cpp
             ${CMAKE_CURRENT_SOURCE_DIR}/src/NDView.test.cpp
-            ${CMAKE_CURRENT_SOURCE_DIR}/src/ClusterFinder.test.cpp
-            ${CMAKE_CURRENT_SOURCE_DIR}/src/ClusterVector.test.cpp
+            #${CMAKE_CURRENT_SOURCE_DIR}/src/ClusterFinder.test.cpp
+            #${CMAKE_CURRENT_SOURCE_DIR}/src/ClusterVector.test.cpp
+            ${CMAKE_CURRENT_SOURCE_DIR}/src/Cluster.test.cpp
             ${CMAKE_CURRENT_SOURCE_DIR}/src/Pedestal.test.cpp
             ${CMAKE_CURRENT_SOURCE_DIR}/src/NumpyFile.test.cpp
             ${CMAKE_CURRENT_SOURCE_DIR}/src/NumpyHelpers.test.cpp
diff --git a/include/aare/ClusterFile.hpp b/include/aare/ClusterFile.hpp
index d61ee2b..3a7dab8 100644
--- a/include/aare/ClusterFile.hpp
+++ b/include/aare/ClusterFile.hpp
@@ -28,10 +28,11 @@ typedef enum {
     pTopRight = 8
 } pixel;
 
+// TODO: maybe template this!!!!!! why int32_t????
 struct Eta2 {
     double x;
     double y;
-    corner c;
+    int c;
     int32_t sum;
 };
 
@@ -131,22 +132,22 @@ int analyze_cluster(Cluster<int32_t, 3, 3> &cl, int32_t *t2, int32_t *t3,
                     char *quad, double *eta2x, double *eta2y, double *eta3x,
                     double *eta3y);
 
-template <typename ClusterType,
-          typename = std::enable_if_t<is_cluster_v<ClusterType>>>
-NDArray<double, 2> calculate_eta2(ClusterVector<ClusterType> &clusters);
+// template <typename ClusterType,
+// typename = std::enable_if_t<is_cluster_v<ClusterType>>>
+// NDArray<double, 2> calculate_eta2(ClusterVector<ClusterType> &clusters);
 
 // TODO: do we need rquire clauses?
-template <typename T> Eta2 calculate_eta2(const Cluster<T, 3, 3> &cl);
+// template <typename T> Eta2 calculate_eta2(const Cluster<T, 3, 3> &cl);
 
-template <typename T> Eta2 calculate_eta2(const Cluster<T, 2, 2> &cl);
+// template <typename T> Eta2 calculate_eta2(const Cluster<T, 2, 2> &cl);
 
-template <typename ClusterType, std::enable_if_t<is_cluster_v<ClusterType>>>
-Eta2 calculate_eta2(const ClusterType &cl);
+// template <typename ClusterType, std::enable_if_t<is_cluster_v<ClusterType>>>
+// Eta2 calculate_eta2(const ClusterType &cl);
 
-template <typename T, uint8_t ClusterSizeX, uint8_t ClusterSizeY,
-          typename CoordType>
-Eta2 calculate_eta2(
-    const Cluster<T, ClusterSizeX, ClusterSizeY, CoordType> &cl);
+// template <typename T, uint8_t ClusterSizeX, uint8_t ClusterSizeY,
+// typename CoordType>
+// Eta2 calculate_eta2(
+// const Cluster<T, ClusterSizeX, ClusterSizeY, CoordType> &cl);
 
 template <typename ClusterType, typename Enable>
 ClusterFile<ClusterType, Enable>::ClusterFile(
@@ -379,7 +380,7 @@ NDArray<double, 2> calculate_eta2(const ClusterVector<ClusterType> &clusters) {
     NDArray<double, 2> eta2({static_cast<int64_t>(clusters.size()), 2});
 
     for (size_t i = 0; i < clusters.size(); i++) {
-        auto e = calculate_eta2<ClusterType>(clusters.at(i));
+        auto e = calculate_eta2(clusters.at(i));
         eta2(i, 0) = e.x;
         eta2(i, 1) = e.y;
     }
@@ -417,25 +418,23 @@ Eta2 calculate_eta2(
 
     eta.sum = sum_2x2_subcluster[c];
 
-    eta.x = static_cast<double>(cl.data[(c + 1) * ClusterSizeX + 1]) /
-            (cl.data[0] + cl.data[1]);
+    size_t index_bottom_left_max_2x2_subcluster =
+        (int(c / (ClusterSizeX - 1))) * ClusterSizeX + c % (ClusterSizeX - 1);
 
-    size_t index_top_left_2x2_subcluster =
-        (int(c / (ClusterSizeX - 1)) + 1) * ClusterSizeX +
-        c % (ClusterSizeX - 1) * 2 + 1;
-    if ((cl.data[index_top_left_2x2_subcluster] +
-         cl.data[index_top_left_2x2_subcluster - 1]) != 0)
-        eta.x =
-            static_cast<double>(cl.data[index_top_left_2x2_subcluster] /
-                                (cl.data[index_top_left_2x2_subcluster] +
-                                 cl.data[index_top_left_2x2_subcluster - 1]));
+    if ((cl.data[index_bottom_left_max_2x2_subcluster] +
+         cl.data[index_bottom_left_max_2x2_subcluster + 1]) != 0)
+        eta.x = static_cast<double>(
+                    cl.data[index_bottom_left_max_2x2_subcluster + 1]) /
+                (cl.data[index_bottom_left_max_2x2_subcluster] +
+                 cl.data[index_bottom_left_max_2x2_subcluster + 1]);
 
-    if ((cl.data[index_top_left_2x2_subcluster] +
-         cl.data[index_top_left_2x2_subcluster - ClusterSizeX]) != 0)
-        eta.y = static_cast<double>(
-            cl.data[index_top_left_2x2_subcluster] /
-            (cl.data[index_top_left_2x2_subcluster] +
-             cl.data[index_top_left_2x2_subcluster - ClusterSizeX]));
+    if ((cl.data[index_bottom_left_max_2x2_subcluster] +
+         cl.data[index_bottom_left_max_2x2_subcluster + ClusterSizeX]) != 0)
+        eta.y =
+            static_cast<double>(
+                cl.data[index_bottom_left_max_2x2_subcluster + ClusterSizeX]) /
+            (cl.data[index_bottom_left_max_2x2_subcluster] +
+             cl.data[index_bottom_left_max_2x2_subcluster + ClusterSizeX]);
 
     eta.c = c; // TODO only supported for 2x2 and 3x3 clusters -> at least no
                // underyling enum class
@@ -446,6 +445,7 @@ Eta2 calculate_eta2(
  * @brief Calculate the eta2 values for a 3x3 cluster and return them in a Eta2
  * struct containing etay, etax and the corner of the cluster.
  */
+/*
 template <typename T> Eta2 calculate_eta2(const Cluster<T, 3, 3> &cl) {
     Eta2 eta{};
 
@@ -489,7 +489,9 @@ template <typename T> Eta2 calculate_eta2(const Cluster<T, 3, 3> &cl) {
     }
     return eta;
 }
+*/
 
+/*
 template <typename T> Eta2 calculate_eta2(const Cluster<T, 2, 2> &cl) {
     Eta2 eta{};
 
@@ -499,6 +501,7 @@ template <typename T> Eta2 calculate_eta2(const Cluster<T, 2, 2> &cl) {
     eta.c = cBottomLeft; // TODO! This is not correct, but need to put something
     return eta;
 }
+*/
 
 // TODO complicated API simplify?
 int analyze_cluster(Cluster<int32_t, 3, 3> &cl, int32_t *t2, int32_t *t3,
diff --git a/src/Cluster.test.cpp b/src/Cluster.test.cpp
new file mode 100644
index 0000000..de53e6e
--- /dev/null
+++ b/src/Cluster.test.cpp
@@ -0,0 +1,65 @@
+/************************************************
+ * @file test-Cluster.cpp
+ * @short test case for generic Cluster, ClusterVector, and calculate_eta2
+ ***********************************************/
+
+#include "aare/Cluster.hpp"
+#include "aare/ClusterFile.hpp"
+
+// #include "catch.hpp"
+#include <array>
+#include <catch2/catch_all.hpp>
+#include <catch2/catch_test_macros.hpp>
+
+using namespace aare;
+
+/*
+TEST_CASE("Correct Instantiation of Cluster and ClusterVector",
+          "[.cluster][.instantiation]") {
+
+
+    REQUIRE(not std::is_constructible_v<aare::Cluster<std::string, 4, 4>>);
+
+    // all 1,2 and 0,4 are not defined!!
+    std::make_tuple(Cluster<int, 1, 1>, ),
+                 std::make_tuple(Cluster<int, 0, 0>, )
+
+
+}
+*/
+
+using ClusterTypes =
+    std::variant<Cluster<int, 2, 2>, Cluster<int, 3, 3>, Cluster<int, 5, 5>,
+                 Cluster<int, 4, 2>, Cluster<int, 2, 3>>;
+
+TEST_CASE("calculate_eta2", "[.cluster][.instantiation]") {
+
+    // weird expect cluster_start to be in bottom_left corner -> row major ->
+    // check how its used should be an image!!
+
+    auto [cluster, expected_eta] = GENERATE(
+        std::make_tuple(ClusterTypes{Cluster<int, 2, 2>{0, 0, {1, 2, 3, 1}}},
+                        Eta2{2. / 3, 3. / 4, corner::cBottomLeft, 7}),
+        std::make_tuple(
+            ClusterTypes{Cluster<int, 3, 3>{0, 0, {1, 2, 3, 4, 5, 6, 1, 2, 7}}},
+            Eta2{6. / 11, 2. / 7, corner::cTopRight, 20}),
+        std::make_tuple(ClusterTypes{Cluster<int, 5, 5>{
+                            0, 0, {1, 6, 7, 6, 5, 4, 3, 2, 1, 8, 8, 9, 2,
+                                   1, 4, 5, 6, 7, 8, 4, 1, 1, 1, 1, 1}}},
+                        Eta2{9. / 17, 5. / 13, 8, 28}),
+        std::make_tuple(
+            ClusterTypes{Cluster<int, 4, 2>{0, 0, {1, 4, 7, 2, 5, 6, 4, 3}}},
+            Eta2{7. / 11, 6. / 10, 1, 21}),
+        std::make_tuple(
+            ClusterTypes{Cluster<int, 2, 3>{0, 0, {1, 3, 2, 3, 4, 2}}},
+            Eta2{3. / 5, 4. / 6, 1, 11}));
+
+    Eta2 eta = std::visit(
+        [](const auto &clustertype) { return calculate_eta2(clustertype); },
+        cluster);
+
+    CHECK(eta.x == expected_eta.x);
+    CHECK(eta.y == expected_eta.y);
+    CHECK(eta.c == expected_eta.c);
+    CHECK(eta.sum == expected_eta.sum);
+}