Top panel: optical (Digitized Sky Survey – DSS2, F+R) image of the region studied in this work. The black squares indicate the GMOS 1–4 fields of Table 1. The dashed green circle shows the Sh 2-295 H II region (Sharpless 1959). Bottom panel: GMOS R pre-images used to prepare GMOS masks. To facilitate the identification of the co-ordinate system orientation in each image, the grid lines corresponding to RA and Dec are plotted in grey as dashed and solid lines, respectively. The position of the slits are shown by open blue squares. In both panels, orange lines represent A_V = 1 and A_V = 3 mag contours (Cambrésy, priv. commun.) and open magenta circles indicate X-ray sources (Santos-Silva et al. 2018). Note that not all X-ray sources were covered by the GMOS observations.