diff --git a/launch/msckf_vio_tum.launch b/launch/msckf_vio_tum.launch
index a28de3f..eca1ebc 100644
--- a/launch/msckf_vio_tum.launch
+++ b/launch/msckf_vio_tum.launch
@@ -21,10 +21,10 @@
       <param name="PHOTOMETRIC" value="true"/>
 
       <!-- Debugging Flaggs -->
-      <param name="PrintImages" value="false"/>
+      <param name="PrintImages" value="true"/>
       <param name="GroundTruth" value="false"/>
 
-      <param name="patch_size_n" value="3"/>
+      <param name="patch_size_n" value="7"/>
       <!-- Calibration parameters -->
       <rosparam command="load" file="$(arg calibration_file)"/>
 
diff --git a/src/msckf_vio.cpp b/src/msckf_vio.cpp
index 16a5951..174be4a 100644
--- a/src/msckf_vio.cpp
+++ b/src/msckf_vio.cpp
@@ -1303,7 +1303,7 @@ void MsckfVio::PhotometricMeasurementJacobian(
     photo_z.push_back(feature.PixelIrradiance(p_in_c0, frame));
 
       //calculate photom. residual
-    photo_r.push_back(photo_z[count] - estimate_photo_z[count]);
+    photo_r.push_back((photo_z[count] - estimate_photo_z[count]));
 
     //cout << "residual: " << photo_r.back() << endl;
 
@@ -1314,8 +1314,8 @@ void MsckfVio::PhotometricMeasurementJacobian(
     // frame derivative calculated convoluting with kernel [-1, 0, 1]
     dx = feature.PixelIrradiance(cv::Point2f(p_in_anchor.x+1, p_in_anchor.y), anchor_frame) - feature.PixelIrradiance(cv::Point2f(p_in_anchor.x-1, p_in_anchor.y), anchor_frame);
     dy = feature.PixelIrradiance(cv::Point2f(p_in_anchor.x, p_in_anchor.y+1), anchor_frame) - feature.PixelIrradiance(cv::Point2f(p_in_anchor.x, p_in_anchor.y-1), anchor_frame);
-    dI_dhj(0, 0) = dx/(pixelDistance.x*N*N);
-    dI_dhj(0, 1) = dy/(pixelDistance.y*N*N);
+    dI_dhj(0, 0) = dx/(pixelDistance.x);
+    dI_dhj(0, 1) = dy/(pixelDistance.y);
 
     gradientVector.x += dx;
     gradientVector.y += dy;