Measured intensities in the different pixels of Fig. A.3 as seen by GREAT and PACS. Green asterisks represent the footprint around IRS 1 and black plus signs the footprint at the outer interface when both data sets are resampled to a common 12′′ resolution (Fig. A.3b). Blue diamonds and orange triangles are obtained when we resample the GREAT data to the 25 pixels of the PACS array using the 9′′ PSF of PACS for the IRS 1 region and the interface, respectively (Fig. A.3a). The brown line shows the identity.