Comparison of smoothing methods. Images generated from the surface brightness maps, by transforming the surface brightness to counts, and adding background noise to emulate a surface brightness limit of 29 mag arcsec⁻². The left and centre images correspond to a smoothing length equal to the distances to the 16th nearest neighbour multiplied by a factor of 0.3 (left) and a factor of 0.6 (centre). The right panel shows the image produced with a different smoothing length, considering the distance to the fifth neighbour.