Postcard image retrieved from the Herschel Science Archive (HSA) of a typical observation from those listed in Table 1, produced by the standard processing pipeline. OJ 287 is at the centre of the field; all other sources are field galaxies. There is a field galaxy ≈32 arcsec north-west of OJ 287, which is clearly resolved at 250 μ m, but increasingly involved with the blazar at 350 and 500 μ m. This galaxy has a flux lower by an order of magnitude than OJ 287 at 250 and 500 μ m and a flux lower by a factor of ≈7 than OJ 287 at 350 μm.