B-field recovery rate for all the synthetic observations at λ = 0.8 mm. Individual points correspond to those of Table A.1, while the cross symbols and vertical bars correspond to the averaged values and their standard variation for the two cases defined in Table 3, respectively: moderate (μ = 3.33) and weak (μ > 6) magnetic fields. The values are separated in three spatial scales (indicated at the bottom of the figure), and slightly shifted for the sake of clarity for the three evolutionary stages given by the protostellar mass indicated at the top of the figure.