SPIRE/HFI pixel-to-pixel comparison at 545  GHz in one 6.3 deg² field from the Herschel infrared Galactic Plane Survey (Molinari et al. 2010). The red line is the result of a linear fit while the black line has a slope of unity. On the left are shown the HFI and SPIRE maps, together with the difference of the two. The difference is displayed between −6.3 and 6.3 MJy sr^-1.