diff --git a/python/damask/_grid.py b/python/damask/_grid.py
index 68e93d81c..7fef8be6f 100644
--- a/python/damask/_grid.py
+++ b/python/damask/_grid.py
@@ -17,6 +17,7 @@ from . import util
 from . import grid_filters
 from . import Rotation
 from . import Table
+from . import Colormap
 from ._typehints import FloatSequence, IntSequence
 
 class Grid:
@@ -681,11 +682,20 @@ class Grid:
                    header='\n'.join(header), fmt=format_string, comments='')
 
 
-    def show(self) -> None:
-        """Show on screen."""
+    def show(self,
+             colormap: Colormap = Colormap.from_predefined('viridis')) -> None:
+        """
+        Show on screen.
+
+        Parameters
+        ----------
+        colormap : damask.Colormap
+            Colors used to map material IDs.
+
+        """
         v = VTK.from_image_data(self.cells,self.size,self.origin)
         v.add(self.material.flatten(),'material')
-        v.show('material')
+        v.show('material',colormap)
 
 
     def add_primitive(self,
diff --git a/python/damask/_vtk.py b/python/damask/_vtk.py
index ff989ff1a..ff04560ac 100644
--- a/python/damask/_vtk.py
+++ b/python/damask/_vtk.py
@@ -205,7 +205,7 @@ class VTK:
             VTK-based geometry from file.
 
         """
-        if not os.path.isfile(fname):                                                               # vtk has a strange error handling
+        if not os.path.isfile(os.path.expanduser(fname)):                                           # vtk has a strange error handling
             raise FileNotFoundError(f'No such file: {fname}')
         if (ext := Path(fname).suffix) == '.vtk' or dataset_type is not None:
             reader = vtk.vtkGenericDataObjectReader()
@@ -437,7 +437,9 @@ class VTK:
         return writer.GetOutputString()
 
 
-    def show(self,label=None,colormap=Colormap.from_predefined('strain')):
+    def show(self,
+             label: str = None,
+             colormap: Colormap = Colormap.from_predefined('viridis')):
         """
         Render.
 
@@ -476,7 +478,15 @@ class VTK:
 
         ren = vtk.vtkRenderer()
         ren.AddActor(actor)
-        ren.SetBackground(67/255,128/255,208/255)
+        if label is None:
+            ren.SetBackground(67/255,128/255,208/255)
+        else:
+            colormap = vtk.vtkScalarBarActor()
+            colormap.SetLookupTable(lut)
+            colormap.SetTitle(label)
+            colormap.SetMaximumWidthInPixels(width//100)
+            ren.AddActor2D(colormap)
+            ren.SetBackground(0.3,0.3,0.3)
 
         window = vtk.vtkRenderWindow()
         window.AddRenderer(ren)