Electron Backscatter Diffraction (EBSD) has become increasingly popular over the last few decades and is now an established and widely used method for the microstructure analysis of crystalline materials. Technical progress in acquisition hardware and software has allowed for ever shorter acquisition times, so that images can often be acquired in minutes rather than hours. However, in order to perform reliable and fast EBSD studies, it is necessary to prepare samples reproducibly and as free from deformation as possible. In the case of metastable metals, where deformation-induced phase transformations can occur, the preparation process is even more important. They are of particular interest, because EBSD can be applied to these materials to investigate the transformation behavior with regard to its influence on the mechanical properties. Using the metastable austenitic steel AISI 347 (X6CrNiNb18-10), various electropolishing parameters were evaluated by means of EBSD and hardness testing. Depending on the polishing process, differences in the Kernel Average Misorientation (KAM) and even in the hardness can be observed, even when more than 97% of the points had a confidence index above 0.1 in both conditions. Struers A2 was always used as the electrolyte in the LectroPol-5 device. Different surface characteristics could be achieved simply by only varying the parameters voltage, flow rate and polishing time, although EBSD indexing was possible. Depending on the parameter combinations chosen, differences in hardness of up to 45 HV 0.5 and in Kernel Average Misorientation distributions could be detected on otherwise identical samples. Finally, in a case study, the microstructure distribution of a bar material with a diameter of 153 mm made from AISI 347 was characterized over the entire cross-section using the established parameter set.