(Top) Model uncertainties for the fluorescence spectrum of Ni I, calculated as the standard deviation of fluorescence efficiencies as a percentage of the value with the default transition rate following 10⁵ iterations within the limits of  ± ​​​​​​the Atomic Spectra Database (ASD) accuracy (see Table 1 of the published article) versus the ASD accuracy rating for 163 selected nickel transitions with model uncertainties <100%. Axis limits were restricted to enhance the visibility of the majority (>99%) of lines within this criterion. Strong and weak lines are offset ±1% vertically with respect to moderate lines for visibility; for definitions of line classifications, see text in the published article. (Bottom) Fe I model uncertainties versus ASD accuracy ratings for 645 transitions with uncertainties lower than 100%.