Luminosity function for AK3 J091606.48-002328. The magenta dots represent the total counts coming from the region inside r₂₀₀; the green dots represent the background counts coming from the background annulus only; and the black dots refer to the background subtracted counts, fitted by a Schechter function (black solid line) in the magnitude range delimited by the two grey vertical dotted lines. Inset: The confidence plot for the values of α and M_⋆ resulting from the fit; the contours at 1σ and 3σ are reported.