Peak-to-peak TTV amplitudes of the sinusoidal approximation of all of the planets that were analysed in this study. Black points are fits to the pre-extracted timings published by Rowe et al. (2015), which for Kepler-128 and Kepler-60 correspond to the red-dashed curves in Figs. 4 and 5. The coloured diamonds show the peak-to-peak amplitude of the sinusoidal approximation of the best fit of the photo-dynamical model (the green dashed curves in Figs. 4 and 5). The colour indicates the S/N_i of the planet. The agreement between pre-extracted timings and photo-dynamical fit is reduced for lower S/N_i. This is further highlighted in Fig. 7.