Overview of the results of the analysis of the FORS 2 data of CPD −62° 2124, collected during the night of 2015 March 17, considering the hydrogen lines, using the Potsdam pipeline. Top left panel: observed Stokes I spectrum arbitrarily normalized to the highest value. Top right panel: the top profile shows Stokes V (in %), while the bottom profile shows the spectrum of the N parameter (in %). The Stokes V spectrum is shifted upward by 0.9% for better visibility. The regions used to calculate the longitudinal magnetic field are indicated by horizontal lines close to the top of the panel. Bottom left panel: linear fit to Stokes V. Bottom middle panel: linear fit to the N spectrum. From the linear fit, we determine ⟨N_z⟩ = 28 ± 102 G. Bottom right panel: distribution of the longitudinal magnetic field values P(⟨B_z⟩), which were obtained via bootstrapping. From the distribution P(⟨B_z⟩), we obtain the most likely value for the longitudinal magnetic field ⟨B_z⟩ = 4636 ± 128 G. The gaps in the region around Hδ in the two upper panels result from masking an internal reflection in that spectral range.