Change the colour of the background of vtkImageReslice for areas out of the region of the surface

Hi everybody,

I have a doubt, i am getting certain planes of a surface with vtkImageReslice but i found that these regions outside the volume are painted in a weird colour different to black. I read that there is a bug but someone knows how to solve it?

I have tried to use SetBackgroundColor and SetLevel but as i read these functions do not work because of a bug of this class. I updated the new version of vtk but i saw this is not fixed yet.