[Paraview] Volume Representation very weak in ParaView3

[Michael Martinec]

Hi

If I open the *.vtk file (link below) and use the Volume representation, 
the outcome is very weak. Opacity is set to 1.0 and playing with the 
color ranges have not worked either. Is there a solution to this problem 
or is this normal?

Link to the file: http://www.freespeed.ch/paraview/solution.vtu
Example of the weak image: 
http://www.freespeed.ch/paraview/weakVolumeRep.jpg

Many thanx in advance
*Michael Martinec