Getting blue slice instead of grayscale vtkCutter

Hi everyone!

I’m reading uint16 numpy array using vtkImageImport and them try to cut one slice from this volume but I get a blue image only, whreas the volume is rendered in grayscale as needed. Could anyone please suggest why am I getting this blue image when cutting?

Here is a part of code I use:

for reading:
dataImporter = vtk.vtkImageImport()
dataImporter.SetImportVoidPointer(image)
if image.dtype == np.uint8:
dataImporter.SetDataScalarTypeToUnsignedChar()
elif image.dtype == np.uint16:
dataImporter.SetDataScalarTypeToUnsignedShort()
dataImporter.SetNumberOfScalarComponents(1)

for cutting:
def cut_plane(self, j, obj, slices):
import vtk

    # Create a plane to cut
    # XZ = (1,0,0) XY = (0,0,1), YZ = (0,1,0)
    plane = vtk.vtkPlane()
    plane.SetOrigin(slices[::-1])
    if j == 1:
        # axial
        plane.SetNormal(0, 0, 1)
    elif j == 2:
        plane.SetNormal(0, 1, 0)
    elif j == 3:
        plane.SetNormal(1, 0, 0)

    cutter = vtk.vtkCutter()
    cutter.SetCutFunction(plane)
    cutter.SetInputData(obj.GetMapper().GetInput())
    cutter.Update()

    return cutter

Thank you!
Helga.