Continuum determination is shown in the top panel. The lower panels are zooms of the regions around 7.7 μm (left) and 14 μm (right). The red line represents the dust fit performed in Section 3. The dashed blue line is the continuum resulting from using a small width Savitzky-Golay filter. The final masked continuum adopted in this work is the solid blue line while the windows masked are represented by horizontal lines at the bottom of each panel