[vtkusers] Spacing lost in vtkImageAppend

[Georg Ziegler]

Hello!

I have a problem with the following code snippet.
The first output yields the correct spacing for each image. (Which is 
not equal to 1,1,1)
The spacing of the output of vtkImageAppend is reset to the default 
spacing of (1,1,1).
Is that a feature or a bug? Am I not using vtkImageAppend in the right way?

for (unsigned long i = 0; i < this->GetSizeZ();i++)
{
     this->GetMeasurementPlaneAt(i)->Update();
     std::cout<<"pre appender"<<
     this->GetMeasurementPlaneAt(i)->GetOutput()->GetSpacing()[0] <<
     std::endl;

     this->appender->AddInputConnection(0,
     this->GetMeasurementPlaneAt(i)->GetOutputPort());
}
this->appender->Update();
std::cout<<"post appender 
"<<appender->GetOutput()->GetSpacing()[0]<<std::endl;

It says in the documentation
http://www.vtk.org/doc/nightly/html/classvtkImageAppend.html
(http://www.vtk.org/doc/release/5.6/html/a00823.html)
that origin and spacing of the first input are used. Obviously this is 
not the case here.

I'm using vtk 5.6.

Regards,
Georg