5σ contrast curves of the gvAPP180 datasets with TRAP. The contrast curve is calculated as five times the median of a three-pixel-wide annulus as a function of separation in the normalised uncertainty map. Left panel: the contrast curves of the upper dark region of cube A of the HR 2562 dataset reduced by choosing reference pixels exclusively from the dark hole (labelled as ‘dark’) or both dark and bright sides (labelled as ‘dark and bright’). The detection significance of HR 2562 В is also marked in the figure. Right panel: the contrast curves of the dark region of the Altair dataset reduced by choosing reference pixels only from the dark hole or both dark and bright sides. The contrast curve of the transition region is also compared in the right panel, which is not much worse than that of the dark region.