Image reconstructions of R Scl from Fig. 9 divided by the model images from Fig. 8 in order to remove the global center-to-limb intensity variation and to highlight the surface structure on top of this variation. We use a cut-off radius at a model intensity level of 50%, located slightly within the Rosseland radius, which is indicated by the black dashed circle. We calculated the maximum, minimum, and mean intensities inside the cut-off radius to estimate the contrast of the observed structure and printed them on the image. These values are normalized to an average intensity of unity for each spectral channel separately. Contours are drawn at levels of 0.9, 0.7, 0.5.