diff --git a/src/camera_calibration.cpp b/src/camera_calibration.cpp
index a64ece0..e34dde2 100644
--- a/src/camera_calibration.cpp
+++ b/src/camera_calibration.cpp
@@ -1152,7 +1152,7 @@ void CameraCali::FindCornersArucoCharuco(const string& write_dir, bool verbose,
     two_d_point_coordinates_dense.resize(number_images, twod);
     points_present.resize(number_images, vector<bool>(number_squares, false));
 
-#pragma omp parallel for private(b_color, global_index)
+#pragma omp parallel for private(b_color, global_index, filename)
     for (int i = 0; i < number_images; i++){
 
         vector< vector<cv::Point2f> > charuco_corners_all;
@@ -1309,7 +1309,7 @@ void CameraCali::FindCornersCharuco(const string& write_dir, bool write_internal
 
     int internal_found_counter = 0;
 
-#pragma omp parallel for private(b_color, global_index)
+#pragma omp parallel for private(b_color, global_index, filename)
     for (int i = 0; i < number_images; i++){
 
         vector< int > ids;
diff --git a/src/solving_structure.cpp b/src/solving_structure.cpp
index abacfd8..58b81bd 100644
--- a/src/solving_structure.cpp
+++ b/src/solving_structure.cpp
@@ -486,7 +486,7 @@ void CeresProblemClass::SolveWriteBackToMC(MCcali& MC, std::ofstream& out, int i
 
 
 	Solver::Options options;
-	options.linear_solver_type = ceres::DENSE_QR;
+	options.linear_solver_type = ceres::DENSE_SCHUR;
 
 	options.minimizer_progress_to_stdout = output_to_terminal;
 	options.num_threads = omp_get_max_threads();