Differences between reconstructions using the methods CEA17 (green), UEA21 (light blue), SvSc16 (purple), VHS24 (black), and HoSc98 (red), and the original RGO group number series for different acuities. The reconstructions were done for the entire period of RGO record. Shown are the RMS (a), mean (b), relative unsigned (c), and maximum absolute (d) differences. We note that by design, CEA17 and UEA21 are identical in these metrics in this case. The vertical dashed lines indicate the acuity threshold beyond which the respective method excludes the observer based on its quality criteria (see Sect. 2.2).