In order to predict the behavior of the materials, it is important to make an effort for optimizing the precision in measuring values which characterize the material microstructure. A parameter of metals is known to give many problems in that sense, since difficulties in its measurement are found and its value is many times measured with a poor precision. The concerned micro-structural propriety is the dislocation density. Main techniques for measuring the dislocation density are the Transmission electron microscopy (TEM) and the Electron Channeling Contrast Imaging (ECCI), thanks who a direct visualization of dislocations can be achieved. However, these methods require a lot of time and a not negligible background in crystallography since dislocations are visible just in specific orientations (Two Beam conditions).