diff --git a/examples/CreateSFMExampleData.cpp b/examples/CreateSFMExampleData.cpp
index 602d396d9..aa0bde8f6 100644
--- a/examples/CreateSFMExampleData.cpp
+++ b/examples/CreateSFMExampleData.cpp
@@ -51,7 +51,7 @@ void createExampleBALFile(const string& filename, const vector<Point3>& P,
 
     // Project points in both cameras
     for (size_t i = 0; i < 2; i++)
-    track.Measurements.push_back(make_pair(i, data.cameras[i].project(p)));
+    track.measurements.push_back(make_pair(i, data.cameras[i].project(p)));
 
     // Add track to data
     data.tracks.push_back(track);
diff --git a/examples/SFMExampleExpressions_bal.cpp b/examples/SFMExampleExpressions_bal.cpp
index fd9ef5648..3768ee2a3 100644
--- a/examples/SFMExampleExpressions_bal.cpp
+++ b/examples/SFMExampleExpressions_bal.cpp
@@ -77,7 +77,7 @@ int main(int argc, char* argv[]) {
   for (const SfmTrack& track : mydata.tracks) {
     // Leaf expression for j^th point
     Point3_ point_('p', j);
-    for (const SfmMeasurement& m : track.Measurements) {
+    for (const SfmMeasurement& m : track.measurements) {
       size_t i = m.first;
       Point2 uv = m.second;
       // Leaf expression for i^th camera
diff --git a/examples/SFMExample_bal.cpp b/examples/SFMExample_bal.cpp
index 4572d8424..ffb5b195b 100644
--- a/examples/SFMExample_bal.cpp
+++ b/examples/SFMExample_bal.cpp
@@ -55,7 +55,7 @@ int main (int argc, char* argv[]) {
   // Add measurements to the factor graph
   size_t j = 0;
   for(const SfmTrack& track: mydata.tracks) {
-    for(const SfmMeasurement& m: track.Measurements) {
+    for(const SfmMeasurement& m: track.measurements) {
       size_t i = m.first;
       Point2 uv = m.second;
       graph.emplace_shared<MyFactor>(uv, noise, C(i), P(j)); // note use of shorthand symbols C and P
diff --git a/examples/SFMExample_bal_COLAMD_METIS.cpp b/examples/SFMExample_bal_COLAMD_METIS.cpp
index d378d89c3..b79a9fa28 100644
--- a/examples/SFMExample_bal_COLAMD_METIS.cpp
+++ b/examples/SFMExample_bal_COLAMD_METIS.cpp
@@ -59,7 +59,7 @@ int main(int argc, char* argv[]) {
   // Add measurements to the factor graph
   size_t j = 0;
   for (const SfmTrack& track : mydata.tracks) {
-    for (const SfmMeasurement& m : track.Measurements) {
+    for (const SfmMeasurement& m : track.measurements) {
       size_t i = m.first;
       Point2 uv = m.second;
       graph.emplace_shared<MyFactor>(
diff --git a/gtsam/gtsam.i b/gtsam/gtsam.i
index b3792fbec..5334a233d 100644
--- a/gtsam/gtsam.i
+++ b/gtsam/gtsam.i
@@ -2759,11 +2759,20 @@ virtual class EssentialMatrixFactor : gtsam::NoiseModelFactor {
 };
 
 #include <gtsam/slam/dataset.h>
-// Dummy classes, for MATLAB wrappers
-class SfmMeasurement{};
-class SiftIndex{ };
-class SfmMeasurements{};
-class SfmCamera{};
+class SfmMeasurement{
+  SfmMeasurement();
+  size_t i() const;
+  Point2 j() const;
+};
+class SiftIndex{
+  SiftIndex();
+  size_t i() const;
+  size_t j() const;
+ };
+class SfmMeasurements{
+  SfmMeasurements();
+
+};
 
 class SfmTrack {
   SfmTrack();
@@ -2772,7 +2781,7 @@ class SfmTrack {
   void setP(gtsam::Point3& p_);
   gtsam::SfmMeasurement measurement(size_t idx) const;
   gtsam::SiftIndex siftIndex(size_t idx) const;
-  void add_measurement(pair<size_t, gtsam::Point2> m);
+  void add_measurement(const pair<size_t, gtsam::Point2>& m);
   SfmMeasurements& measurements();
 };
 
@@ -2782,8 +2791,8 @@ class SfmData {
   size_t number_tracks() const;
   gtsam::PinholeCamera<gtsam::Cal3Bundler> camera(size_t idx) const;
   gtsam::SfmTrack track(size_t idx) const;
-  void add_track(gtsam::SfmTrack t);
-  void add_camera(gtsam::SfmCamera cam);
+  void add_track(const gtsam::SfmTrack& t) ;
+  void add_camera(const gtsam::SfmCamer& cam);
 };
 
 gtsam::SfmData readBal(string filename);
diff --git a/gtsam/slam/SmartFactorBase.h b/gtsam/slam/SmartFactorBase.h
index 5afc159bd..d9f2b9c3d 100644
--- a/gtsam/slam/SmartFactorBase.h
+++ b/gtsam/slam/SmartFactorBase.h
@@ -144,8 +144,8 @@ protected:
   template<class SFM_TRACK>
   void add(const SFM_TRACK& trackToAdd) {
     for (size_t k = 0; k < trackToAdd.number_measurements(); k++) {
-      this->measured_.push_back(trackToAdd.Measurements[k].second);
-      this->keys_.push_back(trackToAdd.Measurements[k].first);
+      this->measured_.push_back(trackToAdd.measurements[k].second);
+      this->keys_.push_back(trackToAdd.measurements[k].first);
     }
   }
 
diff --git a/gtsam/slam/dataset.cpp b/gtsam/slam/dataset.cpp
index 9b610b231..270dbeb95 100644
--- a/gtsam/slam/dataset.cpp
+++ b/gtsam/slam/dataset.cpp
@@ -1052,13 +1052,13 @@ bool readBundler(const string &filename, SfmData &data) {
     size_t nvisible = 0;
     is >> nvisible;
 
-    track.Measurements.reserve(nvisible);
+    track.measurements.reserve(nvisible);
     track.siftIndices.reserve(nvisible);
     for (size_t k = 0; k < nvisible; k++) {
       size_t cam_idx = 0, point_idx = 0;
       float u, v;
       is >> cam_idx >> point_idx >> u >> v;
-      track.Measurements.emplace_back(cam_idx, Point2(u, -v));
+      track.measurements.emplace_back(cam_idx, Point2(u, -v));
       track.siftIndices.emplace_back(cam_idx, point_idx);
     }
 
@@ -1089,7 +1089,7 @@ bool readBAL(const string &filename, SfmData &data) {
     size_t i = 0, j = 0;
     float u, v;
     is >> i >> j >> u >> v;
-    data.tracks[j].Measurements.emplace_back(i, Point2(u, -v));
+    data.tracks[j].measurements.emplace_back(i, Point2(u, -v));
   }
 
   // Get the information for the camera poses
@@ -1163,7 +1163,7 @@ bool writeBAL(const string &filename, SfmData &data) {
 
     for (size_t k = 0; k < track.number_measurements();
          k++) { // for each observation of the 3D point j
-      size_t i = track.Measurements[k].first; // camera id
+      size_t i = track.measurements[k].first; // camera id
       double u0 = data.cameras[i].calibration().u0();
       double v0 = data.cameras[i].calibration().v0();
 
@@ -1173,9 +1173,9 @@ bool writeBAL(const string &filename, SfmData &data) {
              << endl;
       }
 
-      double pixelBALx = track.Measurements[k].second.x() -
+      double pixelBALx = track.measurements[k].second.x() -
                          u0; // center of image is the origin
-      double pixelBALy = -(track.Measurements[k].second.y() -
+      double pixelBALy = -(track.measurements[k].second.y() -
                            v0); // center of image is the origin
       Point2 pixelMeasurement(pixelBALx, pixelBALy);
       os << i /*camera id*/ << " " << j /*point id*/ << " "
diff --git a/gtsam/slam/dataset.h b/gtsam/slam/dataset.h
index 2e4c715be..062d8728c 100644
--- a/gtsam/slam/dataset.h
+++ b/gtsam/slam/dataset.h
@@ -220,12 +220,12 @@ struct SfmTrack {
   SfmTrack(): p(0,0,0) {}
   Point3 p; ///< 3D position of the point
   float r, g, b; ///< RGB color of the 3D point
-  std::vector<SfmMeasurement> Measurements; ///< The 2D image projections (id,(u,v))
+  std::vector<SfmMeasurement> measurements; ///< The 2D image projections (id,(u,v))
   std::vector<SiftIndex> siftIndices;
   
   /// Total number of measurements in this track
   size_t number_measurements() const {
-    return Measurements.size();
+    return measurements.size();
   }
   /// Set 3D point
   void setP(Point3& p_){
@@ -234,7 +234,7 @@ struct SfmTrack {
 
   /// Get the measurement (camera index, Point2) at pose index `idx`
   SfmMeasurement measurement(size_t idx) const {
-    return Measurements[idx];
+    return measurements[idx];
   }
   /// Get the SIFT feature index corresponding to the measurement at `idx`
   SiftIndex siftIndex(size_t idx) const {
@@ -243,12 +243,12 @@ struct SfmTrack {
   Point3 point3() const {
     return p;
   }
-  void add_measurement(pair<size_t, gtsam::Point2> m) {
-    Measurements.push_back(m);
+  void add_measurement(pair<size_t, gtsam::Point2>& m) const{
+    measurements.push_back(m);
   }
 
   SfmMeasurements& measurements() {
-    return Measurements;
+    return measurements;
   }
 
 };
@@ -259,7 +259,7 @@ typedef PinholeCamera<Cal3Bundler> SfmCamera;
 
 /// Define the structure for SfM data
 struct SfmData {
-  std::vector<SfmMeasurement> Measurements;
+  std::vector<SfmMeasurement> measurements; ///<Set of measurements in a track
   std::vector<SfmCamera> cameras; ///< Set of cameras
   std::vector<SfmTrack> tracks; ///< Sparse set of points
   size_t number_cameras() const {
@@ -278,11 +278,11 @@ struct SfmData {
     return tracks[idx];
   }
 
-  void add_track(SfmTrack t) {
+  void add_track(SfmTrack& t) const {
     tracks.push_back(t);
   }
 
-  void add_camera(SfmCamera cam){
+  void add_camera(SfmCamera& cam) const{
     cameras.push_back(cam);
   }
 };
diff --git a/gtsam/slam/tests/testDataset.cpp b/gtsam/slam/tests/testDataset.cpp
index ff5cf8b46..aad9124c5 100644
--- a/gtsam/slam/tests/testDataset.cpp
+++ b/gtsam/slam/tests/testDataset.cpp
@@ -166,9 +166,9 @@ TEST( dataSet, Balbianello)
   EXPECT_LONGS_EQUAL(3,track0.number_measurements());
 
   // Check projection of a given point
-  EXPECT_LONGS_EQUAL(0,track0.Measurements[0].first);
+  EXPECT_LONGS_EQUAL(0,track0.measurements[0].first);
   const SfmCamera& camera0 = mydata.cameras[0];
-  Point2 expected = camera0.project(track0.p), actual = track0.Measurements[0].second;
+  Point2 expected = camera0.project(track0.p), actual = track0.measurements[0].second;
   EXPECT(assert_equal(expected,actual,1));
 }
 
@@ -476,9 +476,9 @@ TEST( dataSet, readBAL_Dubrovnik)
   EXPECT_LONGS_EQUAL(3,track0.number_measurements());
 
   // Check projection of a given point
-  EXPECT_LONGS_EQUAL(0,track0.Measurements[0].first);
+  EXPECT_LONGS_EQUAL(0,track0.measurements[0].first);
   const SfmCamera& camera0 = mydata.cameras[0];
-  Point2 expected = camera0.project(track0.p), actual = track0.Measurements[0].second;
+  Point2 expected = camera0.project(track0.p), actual = track0.measurements[0].second;
   EXPECT(assert_equal(expected,actual,12));
 }
 
@@ -557,8 +557,8 @@ TEST( dataSet, writeBAL_Dubrovnik)
 
     // check measurements
     for (size_t k = 0; k < actualTrack.number_measurements(); k++){
-      EXPECT_LONGS_EQUAL(expectedTrack.Measurements[k].first,actualTrack.Measurements[k].first);
-      EXPECT(assert_equal(expectedTrack.Measurements[k].second,actualTrack.Measurements[k].second));
+      EXPECT_LONGS_EQUAL(expectedTrack.measurements[k].first,actualTrack.measurements[k].first);
+      EXPECT(assert_equal(expectedTrack.measurements[k].second,actualTrack.measurements[k].second));
     }
   }
 }
@@ -600,9 +600,9 @@ TEST( dataSet, writeBALfromValues_Dubrovnik){
   EXPECT_LONGS_EQUAL(3,track0.number_measurements());
 
   // Check projection of a given point
-  EXPECT_LONGS_EQUAL(0,track0.Measurements[0].first);
+  EXPECT_LONGS_EQUAL(0,track0.measurements[0].first);
   const SfmCamera& camera0 = writtenData.cameras[0];
-  Point2 expected = camera0.project(track0.p), actual = track0.Measurements[0].second;
+  Point2 expected = camera0.project(track0.p), actual = track0.measurements[0].second;
   EXPECT(assert_equal(expected,actual,12));
 
   Pose3 expectedPose = camera0.pose();
diff --git a/gtsam/slam/tests/testEssentialMatrixFactor.cpp b/gtsam/slam/tests/testEssentialMatrixFactor.cpp
index 6bece036f..95db611d7 100644
--- a/gtsam/slam/tests/testEssentialMatrixFactor.cpp
+++ b/gtsam/slam/tests/testEssentialMatrixFactor.cpp
@@ -46,10 +46,10 @@ EssentialMatrix trueE(trueRotation, trueDirection);
 double baseline = 0.1; // actual baseline of the camera
 
 Point2 pA(size_t i) {
-  return data.tracks[i].Measurements[0].second;
+  return data.tracks[i].measurements[0].second;
 }
 Point2 pB(size_t i) {
-  return data.tracks[i].Measurements[1].second;
+  return data.tracks[i].measurements[1].second;
 }
 Vector vA(size_t i) {
   return EssentialMatrix::Homogeneous(pA(i));
@@ -367,10 +367,10 @@ EssentialMatrix trueE(aRb, Unit3(aTb));
 double baseline = 10; // actual baseline of the camera
 
 Point2 pA(size_t i) {
-  return data.tracks[i].Measurements[0].second;
+  return data.tracks[i].measurements[0].second;
 }
 Point2 pB(size_t i) {
-  return data.tracks[i].Measurements[1].second;
+  return data.tracks[i].measurements[1].second;
 }
 
 boost::shared_ptr<Cal3Bundler> //
diff --git a/gtsam/slam/tests/testSmartProjectionFactor.cpp b/gtsam/slam/tests/testSmartProjectionFactor.cpp
index 1f3a5d1cb..1fd06cc9f 100644
--- a/gtsam/slam/tests/testSmartProjectionFactor.cpp
+++ b/gtsam/slam/tests/testSmartProjectionFactor.cpp
@@ -283,14 +283,14 @@ TEST(SmartProjectionFactor, perturbPoseAndOptimizeFromSfM_tracks ) {
 
   SfmTrack track1;
   for (size_t i = 0; i < 3; ++i) {
-    track1.Measurements.emplace_back(i + 1, measurements_cam1.at(i));
+    track1.measurements.emplace_back(i + 1, measurements_cam1.at(i));
   }
   SmartFactor::shared_ptr smartFactor1(new SmartFactor(unit2));
   smartFactor1->add(track1);
 
   SfmTrack track2;
   for (size_t i = 0; i < 3; ++i) {
-    track2.Measurements.emplace_back(i + 1, measurements_cam2.at(i));
+    track2.measurements.emplace_back(i + 1, measurements_cam2.at(i));
   }
   SmartFactor::shared_ptr smartFactor2(new SmartFactor(unit2));
   smartFactor2->add(track2);
diff --git a/python/gtsam/preamble.h b/python/gtsam/preamble.h
index e6ed64689..8525ed3a3 100644
--- a/python/gtsam/preamble.h
+++ b/python/gtsam/preamble.h
@@ -11,5 +11,4 @@ PYBIND11_MAKE_OPAQUE(std::vector<boost::shared_ptr<gtsam::BetweenFactor<gtsam::P
 PYBIND11_MAKE_OPAQUE(std::vector<boost::shared_ptr<gtsam::BetweenFactor<gtsam::Pose2> > >);
 PYBIND11_MAKE_OPAQUE(std::vector<gtsam::IndexPair>);
 PYBIND11_MAKE_OPAQUE(std::vector<gtsam::SfmMeasurement>);
-PYBIND11_MAKE_OPAQUE(std::vector<gtsam::SiftIndex>);
-PYBIND11_MAKE_OPAQUE(std::vector<gtsam::SfmCamera>);
\ No newline at end of file
+PYBIND11_MAKE_OPAQUE(std::vector<gtsam::SiftIndex>);
\ No newline at end of file
diff --git a/python/gtsam/specializations.h b/python/gtsam/specializations.h
index dcaaa4c76..03e2b606c 100644
--- a/python/gtsam/specializations.h
+++ b/python/gtsam/specializations.h
@@ -14,5 +14,4 @@ py::bind_map<gtsam::IndexPairSetMap>(m_, "IndexPairSetMap");
 py::bind_vector<gtsam::IndexPairVector>(m_, "IndexPairVector");
 py::bind_map<gtsam::KeyPairDoubleMap>(m_, "KeyPairDoubleMap");
 py::bind_vector<std::vector<gtsam::SfmMeasurement> >(m_, "Measurement");
-py::bind_vector<std::vector<gtsam::SiftIndex> >(m_, "SiftIndexVector");
-py::bind_vector<std::vector<gtsam::SfmCamera> >(m_, "cameras");
\ No newline at end of file
+py::bind_vector<std::vector<gtsam::SiftIndex> >(m_, "SiftIndexVector");
\ No newline at end of file
diff --git a/tests/testGeneralSFMFactorB.cpp b/tests/testGeneralSFMFactorB.cpp
index fafe87d13..05b4c7f66 100644
--- a/tests/testGeneralSFMFactorB.cpp
+++ b/tests/testGeneralSFMFactorB.cpp
@@ -50,7 +50,7 @@ TEST(PinholeCamera, BAL) {
   NonlinearFactorGraph graph;
 
   for (size_t j = 0; j < db.number_tracks(); j++) {
-    for (const SfmMeasurement& m: db.tracks[j].Measurements)
+    for (const SfmMeasurement& m: db.tracks[j].measurements)
       graph.emplace_shared<sfmFactor>(m.second, unit2, m.first, P(j));
   }