    shotNoiseSource = vtkImageNoiseSource()
    shotNoiseSource.SetWholeExtent(extent)
    shotNoiseSource.SetMinimum(0.0)
    shotNoiseSource.SetMaximum(1.0)

    shotNoiseThresh1 = vtkImageThreshold()
--
    shotNoiseSource = vtkImageNoiseSource()
    shotNoiseSource.SetWholeExtent(extent)
    shotNoiseSource.SetMinimum(0.0)
    shotNoiseSource.SetMaximum(1.0)

    shotNoiseThresh1 = vtkImageThreshold()
