Completeness-corrected PNLF for each elliptical bin fitted by both the generalised analytical formula (in blue) and the Ciardullo et al. (1989) analytical LF (in orange). The projected major-axis elliptical radii covered by each bin is indicated along with the fitted slope of the PNLF. The region beyond the limiting magnitude of the shallowest field (Field# 33_4) is shown in grey. The grey dotted line shows the 90% completeness limit of the shallowest field.