DSS2 optical image of the area around the Carina Nebula, with outlines illustrating the spatial extent of the cloud complex (CNC, yellow) and the subgroups of the Car OB1 association. North is up and east to the left. The white grid shows the J2000 celestial coordinates. The yellow line shows the boundary of the cloud emission related to the CNC as traced by the contour for a surface brightness of ≥7.4 mJy/(arcsec)² in the Herschel 160 µm map. The X-ray survey region of the Chandra Carina Complex Project (CCCP) as well as the areas of the additional Chandra observations of NGC 3324 and NGC 3293 are marked with cyan outlines and labeled, the cluster IC 2581 is highlighted in yellow and the white ellipses show the subgroups in Car OB1 as defined in Mel’Nik & Efremov (1995). The area for our cluster search with DBSCAN is marked in green.