Galaxy HRS 157. Top left: XDSS R-band image. Top right: Hα velocity field. Middle left: Hα monochromatic image. Middle right: Hα velocity dispersion field. Bottom left: rotation curve (if computed). Bottom right: residual velocity field (if computed). The black cross is the kinematical center. In the maps, the green line is the morphological major axis, while the black/white line is the estimated kinematical major axis, its length represents the 2 × r_opt. In the rotation curve, blue dots indicate the approaching side while red crosses the receding side, the black solid vertical line represents the r_opt, and the black dashed line represents the r₂₅; the blue solid line the r_eff (if available in Cortese et al. 2012) and the green horizontal line the H IV_max (if available in Boselli et al. 2014a); the solid black curve is the best fit Courteau function to the rotation curve.