In this work, a comparison of three different methods for analysing topographies and roughness on machined metal surfaces is presented. To obtain comparable results, the measurements were done on one and the same set of samples. For this purpose, an atomic force microscope (AFM), a confocal white light microscope, and a scattering light system were used to analyse the topography of samples of the same material, but with the topographies occurring step by step from the grinding process to the polishing process. Based on the results of the investigations with the parametric system (scattering light sensor) and the profilometric systems (AFM, confocal white light microscope), we established a correlation between the roughness parameters and the scattering light parameter. It is shown that the different methods lead to different roughness parameters of the same surface.