diff --git a/examples/vSLAMexample/vSFMexample.cpp b/examples/vSLAMexample/vSFMexample.cpp
index a9f27b0a5..d2b8196eb 100644
--- a/examples/vSLAMexample/vSFMexample.cpp
+++ b/examples/vSLAMexample/vSFMexample.cpp
@@ -146,7 +146,7 @@ int main(int argc, char* argv[]) {
 
   // Optimize the graph
   cout << "*******************************************************" << endl;
-  NonlinearOptimizationParameters::sharedThis params = NonlinearOptimizationParameters::newVerbosity_(Optimizer::Parameters::DAMPED);
+  NonlinearOptimizationParameters::sharedThis params = NonlinearOptimizationParameters::newVerbosity(Optimizer::Parameters::DAMPED);
   Optimizer::shared_values result = Optimizer::optimizeGN(graph, initialEstimates, params);
 
   // Print final results
diff --git a/gtsam/nonlinear/NonlinearOptimizationParameters.h b/gtsam/nonlinear/NonlinearOptimizationParameters.h
index 94d3642d4..6c5930112 100644
--- a/gtsam/nonlinear/NonlinearOptimizationParameters.h
+++ b/gtsam/nonlinear/NonlinearOptimizationParameters.h
@@ -65,19 +65,24 @@ namespace gtsam {
 			verbosity_(parameters.verbosity_), lambdaMode_(parameters.lambdaMode_){}
 
 
-		static sharedThis newVerbosity_(verbosityLevel verbosity) {
+		/* a copy of old instance except some parameters */
+        sharedThis newLambda_(double lambda) const {
+            sharedThis ptr (boost::make_shared<NonlinearOptimizationParameters>(*this)) ;
+            ptr->lambda_ = lambda ;
+            return ptr ;
+        }
+
+
+
+        // static
+        /* new instance with default parameters except some partially assigned parameters */
+		static sharedThis newVerbosity(verbosityLevel verbosity) {
 			sharedThis ptr (boost::make_shared<NonlinearOptimizationParameters>()) ;
 			ptr->verbosity_ = verbosity ;
 			return ptr ;
 		}
 
-		static sharedThis newLambda_(double lambda) {
-			sharedThis ptr (boost::make_shared<NonlinearOptimizationParameters>()) ;
-			ptr->lambda_ = lambda ;
-			return ptr ;
-		}
-
-		static sharedThis newMaxIterations_(int maxIterations) {
+		static sharedThis newMaxIterations(int maxIterations) {
 			sharedThis ptr (boost::make_shared<NonlinearOptimizationParameters>()) ;
 			ptr->maxIterations_ = maxIterations ;
 			return ptr ;
diff --git a/gtsam/nonlinear/NonlinearOptimizer-inl.h b/gtsam/nonlinear/NonlinearOptimizer-inl.h
index 805c56b32..8dc6033db 100644
--- a/gtsam/nonlinear/NonlinearOptimizer-inl.h
+++ b/gtsam/nonlinear/NonlinearOptimizer-inl.h
@@ -185,7 +185,6 @@ namespace gtsam {
 		  shared_values newValues(new C(values_->expmap(delta, *ordering_))); // TODO: updateValues
 
 		  // create new optimization state with more adventurous lambda
-		  //NonlinearOptimizer next(newValuesSolverLambda_(newValues, newSolver, lambda / factor));
 		  double error = graph_->error(*newValues);
 
 		  if (verbosity >= Parameters::TRYLAMBDA) cout << "next error = " << error << endl;
diff --git a/gtsam/nonlinear/NonlinearOptimizer.h b/gtsam/nonlinear/NonlinearOptimizer.h
index 3385a1101..d1fc33196 100644
--- a/gtsam/nonlinear/NonlinearOptimizer.h
+++ b/gtsam/nonlinear/NonlinearOptimizer.h
@@ -121,16 +121,14 @@ namespace gtsam {
 		error_(error), ordering_(ordering), solver_(solver), parameters_(parameters), dimensions_(dimensions) {}
 
     /** Create a new NonlinearOptimizer with a different lambda */
-//    This newLambda_(double newLambda) const {
-//      return NonlinearOptimizer(graph_, values_, error_, ordering_, solver_, newLambda, dimensions_); }
-//
-//    This newValuesSolver_(shared_values newValues, shared_solver newSolver) const {
-//      return NonlinearOptimizer(graph_, newValues, graph_->error(*newValues), ordering_, newSolver, lambda_, dimensions_); }
-//
-//    This newValuesSolverLambda_(shared_values newValues, shared_solver newSolver, double newLambda) const {
-//      return NonlinearOptimizer(graph_, newValues, graph_->error(*newValues), ordering_, newSolver, newLambda, dimensions_); }
+    This newValuesSolver_(shared_values newValues, shared_solver newSolver) const {
+      return NonlinearOptimizer(graph_, newValues, graph_->error(*newValues), ordering_, newSolver, parameters_, dimensions_); }
 
-    /** Create a new NonlinearOptimizer with a different lambda */
+    This newValuesErrorLambda_(shared_values newValues, double newError, double newLambda) const {
+      return NonlinearOptimizer(graph_, newValues, newError, ordering_, solver_, parameters_->newLambda_(newLambda), dimensions_); }
+
+
+	/*
     This newLambda_(double newLambda) const {
       return NonlinearOptimizer(graph_, values_, error_, ordering_, solver_, parameters_->newLambda_(newLambda), dimensions_); }
 
@@ -152,7 +150,7 @@ namespace gtsam {
 
     This newMaxIterations_(int maxIterations) const {
       return NonlinearOptimizer(graph_, values_, error_, ordering_, solver_, parameters_->newMaxIterations_(maxIterations), dimensions_); }
-
+    */
 
 	public:
 		/**
@@ -279,9 +277,7 @@ namespace gtsam {
 										shared_values values,
 										Parameters::verbosityLevel verbosity)
 		{
-			Parameters def ;
-			shared_parameters parameters = def.newVerbosity_(verbosity);
-			return optimizeLM(graph, values, parameters);
+			return optimizeLM(graph, values, Parameters::newVerbosity(verbosity));
 		}
 		/**
 		 * Static interface to LM optimization (no shared_ptr arguments) - see above