Resulting periodograms when using a window function on light curves with phase information randomised and with phase information retained. The light curves have been convolved with the Hann window to show the effect of phase randomisation in the iterative step of the EMP13 algorithm. The grey periodogram of the phase-randomised light curve is not affected by the Hann window, and thus it remains flat, similar to the left-side plot of Fig. 8. The black periodogram, with phase information retained, is affected in the same way as the simulations made with the TK95 algorithm. With the TK95 algorithm, the phases are retained, as there is no iterative step.