SDM-disambiguated vector magnetogram using information from the hmi.m_45s series (see Sect. 5) on the SO/PHI-HRT image plane. Panel a: sign function ζ from Eq. (5), saturated at ±5. Panel b: vector magnetogram, with B_los saturated at ±1500 G in grayscale and red and blue arrows representing the transverse field at positive and negative B_los. Panel c: comparison of SDM and ME0 disambiguations, with agreement indicated in black, disagreement in white, and gray indicating pixels that are not considered in the comparison because the SO/PHI-HRT transverse field falls below the noise threshold. In all panels, the 400 G isoline of the SO/PHI-HRT |B_los| is drawn as a solid yellow line. The corresponding vector magnetogram in heliographic projection is shown in Fig. A.1b.