Line profiles in the Ca ii 8542 Å line in the k-NN reference set used in the automated detections of PMJs. (Left) All 168 Ca ii 8542 Å line profiles of by-eye selected positions of PMJs used in the k-NN detection scheme (solid-grey) plotted together with their average (solid-black). (Right) All 790 line profiles of non-PMJ reference positions plotted together with their average (solid-black). For reference in both panels, the averages of the Ca ii 8542 Å line profile over the whole time series are given for the upper left corner of the full-FOV (dashed-grey) and the penumbra (dashed-dotted-grey) (see Fig. 1 for outlines of both areas).