Left: photometric redshift as a function of the spectroscopic one for the 122 J1030 sources with an available spectroscopic redshift. The black solid line marks the z_spec = z_phot relation, while the dashed lines contain the z_phot = z_spec ± 0.15(1 + z_spec) region. Sources within this region are deemed to have a reliable photometric redshift. In the two panels, we highlight different classes of sources which are more likely to have a large fraction of outliers: spectroscopically classified BL–AGNs (blue circles, top); morphologically classified point-like sources (pink triangles, bottom). Right: distribution of Δz/(1 + z_spec) for the sources reported in the left panel. The color code in the right panels matches that in the left panels.