Top: region selection for YSOs in the three Orion B subregions. The background is a Planck HFI image showing dust emission at 545 GHz, while dark-gray shadings indicate regions of higher dust column-density (Planck Collaboration XI 2014). The subregions are highlighted by separate colors: L1630-S (red), L1630-N (blue), and L1622 (green). The black dots are all selected YSO candidates within the whole displayed region that pass the Gaia quality criteria within 300 pc < d < 550 pc. Only those YSOs within the circular selected regions are shown in color if they also pass the proper motion selection (bottom panels). For orientation the three belt stars and σ Ori are labeled and shown with yellow star symbols. The dotted lines are extinction contours (from a Herschel map) and outline the clouds of interest (see also Fig. 3). Bottom: YSO proper motion selection for the three Orion B subregions. The colored dots indicate the proper motion selection and are the same as in the top panel. The black dots are all YSOs within the individual region selections (from top panel) but are excluded by the proper motion selection. The gray background are all sources toward Orion B that pass the quality criteria. See text for more details.