Diagram illustrating the two-step local outlier removal process. The elliptical disk is divided into angular sections based on series of outlier rejections from step 1. Section 1 (green) spans the bright, front-scattering side and undergoes step 1 filtering. Sections 2 (yellow) and 3 (purple) lie on the fainter, back-scattering side and are targeted by the second-stage rejection (black crosses). Red arcs (a bridge) mark angular gaps where the local standard deviation is inflated due to lower S/N, preventing the sliding window from identifying outliers. Defining new sections in these regions enables localised standard deviation recalculation, allowing for successful outlier detection across the back-scattering side.