Stellar density maps of the target region for different colour cuts, with increasing extinction from top to bottom. Each panel indicates the range of the corresponding colour cut. The 50 and 20km/s clouds are marked with orange circular regions, and the ridge is indicated by a dashed orange rectangle. The white star in each panel indicates the position of Sgr A^*. The colour scale represents the number of stars per pixel and is adapted in each panel to the number of stars in the 50 and 20 km/s clouds for an easier comparison with the surrounding area.