This article describes the roughness measurement of deformed surfaces using digital techniques, enabling a comprehensive assessment of roughness parameters in terms of density and slope distribution, Abbott curve, power spectrum, autocorrelation functions, etc. Short and long wavelengths, introduced on the surface by the plastic deformation process, influence its roughness parameters. These long wavelengths are not measured by the commercial roughness measuring methods due to their being rejected as waviness. A new method for determining the ‘n’ value of the material has been suggested. The deformation mechanism and surface roughness have been correlated with the help of power spectrum of the surface.