diff --git a/resample.cxx b/resample.cxx
index e0f0438..dce3504 100644
--- a/resample.cxx
+++ b/resample.cxx
@@ -70,20 +70,19 @@ int DoIt2(int argc, char *argv[], InterpolatorType* interpolator){
 
     typename InputImageType::SpacingType outputSpacing;
     std::vector<itk::ProcessObject::Pointer> savedPointers; // to store smart-pointers outside their creation scope
-    savedPointers.push_back(caster.GetPointer());
-    typedef itk::ImageSource<InternalImageType> ISType;
+    savedPointers.push_back(caster);
 
     for (unsigned int i= 0; i < Dimension; i++){
         outputSpacing[i]= atof(argv[5+i]);
 	
 	typename GaussianFilterType::Pointer smoother = GaussianFilterType::New();
-	smoother->SetInput(dynamic_cast<ISType*>(savedPointers[i].GetPointer())->GetOutput()); // similar to: https://cmake.org/pipermail/insight-users/2007-May/022374.html
+	smoother->SetInput(savedPointers[i]->GetOutput()); // similar to: https://cmake.org/pipermail/insight-users/2007-May/022374.html
 	smoother->SetSigma(outputSpacing[i]);
 	smoother->SetDirection(i);
 	smoother->ReleaseDataFlagOn();
 	smoother->InPlaceOn();
 	FilterWatcher watcherX(smoother);
-	savedPointers.push_back(smoother.GetPointer());
+	savedPointers.push_back(smoother);
 	}
 
     const typename InputImageType::SizeType& inputSize= input->GetLargestPossibleRegion().GetSize();
@@ -98,7 +97,7 @@ int DoIt2(int argc, char *argv[], InterpolatorType* interpolator){
 
     typedef itk::ResampleImageFilter<InternalImageType, OutputImageType> FilterType;
     typename FilterType::Pointer filter= FilterType::New();
-    filter->SetInput(dynamic_cast<ISType*>(savedPointers[savedPointers.size()].GetPointer())->GetOutput());
+    filter->SetInput(savedPointers[savedPointers.size()]->GetOutput());
     filter->SetTransform(transform);
     filter->SetInterpolator(interpolator);
     filter->SetOutputSpacing(outputSpacing);