diff --git a/gtsam/geometry/CameraSet.h b/gtsam/geometry/CameraSet.h
index bb149636b..18f311a23 100644
--- a/gtsam/geometry/CameraSet.h
+++ b/gtsam/geometry/CameraSet.h
@@ -57,7 +57,7 @@ protected:
     Vector b(ZDim * m);
     for (size_t i = 0, row = 0; i < m; i++, row += ZDim) {
       Vector bi = traits<Z>::Local(measured[i], predicted[i]);
-      if(ZDim==3 && std::isnan(bi(1))){ // compensate for the case in which the right pixel in a stereoPoint is missing (nan)
+      if(ZDim==3 && std::isnan(bi(1))){ // if it is a stereo point and the right pixel is missing (nan)
         bi(1) = 0;
       }
       b.segment<ZDim>(row) = bi;
diff --git a/gtsam_unstable/slam/SmartStereoProjectionFactor.h b/gtsam_unstable/slam/SmartStereoProjectionFactor.h
index d46aef535..006ff7bdf 100644
--- a/gtsam_unstable/slam/SmartStereoProjectionFactor.h
+++ b/gtsam_unstable/slam/SmartStereoProjectionFactor.h
@@ -233,15 +233,16 @@ public:
     size_t m = cameras.size();
     bool retriangulate = decideIfTriangulate(cameras);
 
+    // triangulate stereo measurements by treating each stereocamera as a pair of monocular cameras
     MonoCameras monoCameras;
     MonoMeasurements monoMeasured;
     for(size_t i = 0; i < m; i++) {
-      Pose3 leftPose = cameras[i].pose();
-      Cal3_S2 monoCal = cameras[i].calibration().calibration();
-      MonoCamera leftCamera_i(leftPose,monoCal);
-      Pose3 left_Pose_right = Pose3(Rot3(),Point3(cameras[i].baseline(),0.0,0.0));
-      Pose3 rightPose = leftPose.compose( left_Pose_right );
-      MonoCamera rightCamera_i(rightPose,monoCal);
+      const Pose3 leftPose = cameras[i].pose();
+      const Cal3_S2 monoCal = cameras[i].calibration().calibration();
+      const MonoCamera leftCamera_i(leftPose,monoCal);
+      const Pose3 left_Pose_right = Pose3(Rot3(),Point3(cameras[i].baseline(),0.0,0.0));
+      const Pose3 rightPose = leftPose.compose( left_Pose_right );
+      const MonoCamera rightCamera_i(rightPose,monoCal);
       const StereoPoint2 zi = measured_[i];
       monoCameras.push_back(leftCamera_i);
       monoMeasured.push_back(Point2(zi.uL(),zi.v()));
diff --git a/gtsam_unstable/slam/tests/testSmartStereoProjectionPoseFactor.cpp b/gtsam_unstable/slam/tests/testSmartStereoProjectionPoseFactor.cpp
index c4fb32dd7..b17347edb 100644
--- a/gtsam_unstable/slam/tests/testSmartStereoProjectionPoseFactor.cpp
+++ b/gtsam_unstable/slam/tests/testSmartStereoProjectionPoseFactor.cpp
@@ -1348,7 +1348,7 @@ TEST( SmartStereoProjectionPoseFactor, HessianWithRotation ) {
 }
 
 /* *************************************************************************/
-TEST( SmartStereoProjectionPoseFactor, HessianWithRotationDegenerate ) {
+TEST( SmartStereoProjectionPoseFactor, HessianWithRotationNonDegenerate ) {
 
   vector<Key> views;
   views.push_back(x1);
@@ -1381,6 +1381,9 @@ TEST( SmartStereoProjectionPoseFactor, HessianWithRotationDegenerate ) {
   boost::shared_ptr<GaussianFactor> hessianFactor = smartFactor->linearize(
       values);
 
+  // check that it is non degenerate
+  EXPECT(smartFactor->isValid());
+
   Pose3 poseDrift = Pose3(Rot3::Ypr(-M_PI / 2, 0., -M_PI / 2), Point3(0, 0, 0));
 
   Values rotValues;
@@ -1391,6 +1394,9 @@ TEST( SmartStereoProjectionPoseFactor, HessianWithRotationDegenerate ) {
   boost::shared_ptr<GaussianFactor> hessianFactorRot = smartFactor->linearize(
       rotValues);
 
+  // check that it is non degenerate
+  EXPECT(smartFactor->isValid());
+
   // Hessian is invariant to rotations in the nondegenerate case
   EXPECT(
       assert_equal(hessianFactor->information(),
@@ -1407,10 +1413,14 @@ TEST( SmartStereoProjectionPoseFactor, HessianWithRotationDegenerate ) {
   boost::shared_ptr<GaussianFactor> hessianFactorRotTran =
       smartFactor->linearize(tranValues);
 
-  // Hessian is invariant to rotations and translations in the nondegenerate case
+  // Hessian is invariant to rotations and translations in the degenerate case
   EXPECT(
       assert_equal(hessianFactor->information(),
+#ifdef GTSAM_USE_EIGEN_MKL
+          hessianFactorRotTran->information(), 1e-5));
+#else
           hessianFactorRotTran->information(), 1e-6));
+#endif
 }
 
 /* ************************************************************************* */