ΔR evaluated assuming the analytical representation of the ESMB with a detection threshold of S​_max = 0.1 Jy, considering a relative error and including or not including the prefiltering. The curve corresponding to the ideal case is almost superimposed on the green curve, and therefore it is not reported for simplicity. Here (and in the following analogous figures), solid (dots) lines refer to positive (negative) values. See legend for an explanation of the symbols and lines.