Each data subset (a–j) is visualised with two images. The given times represent the middle point of each set. On the left, we show the light-curve inversion result. The spot-filling factor is larger in the darker regions. A light curve represents a one-dimensional time series and, therefore, the resulting stellar image contains information on the spot distribution only in longitudinal direction. On the right, the observed and calculated V-band magnitudes are plotted with crosses and lines, respectively. The length of the set (in days) is given in the upper right corner.