S/N estimates as a function of redshift confidence. The log of the S/N emission or absorption composite narrowband is shown as a function of the log of the leading line S/N derived from pyPlatefit. Low (1), good (2) and high (3) redshift confidences are shown in respectively orange, blue and green colors, while low-z (z < 2.9) and high-z (z > 2.9) sources are displayed in the left and right panels, respectively.