Comparison of different methods to retrieve the quasi-static LO modes associated with NCPAs. The “DIP global” method shows the highest accuracy, especially in the case of larger seeing (right picture). The curves representthe distribution of RMS of the averaged delta wavefront error (ΔWFE). The black dashed line and grey fill show the mean RMS of introduced NCPA realisations (WFE_introduced) with 1σ confidence interval.