Al abundances derived from neutral lines with W_λ,red < 3 × 10⁻5 and high-quality gf values (black bullets), from neutral lines with W_λ,red < 3 × 10⁻5 and/or low-quality gf values (open bullets), and from singly ionised lines (red bullets) in LTE (left) and NLTE (right). The black horizontal lines and grey-shaded regions correspond to the mean and one sigma standard deviation of the lines marked with filled black bullets.