Photometry thumbnail image grid for NGC 4559. CAAPR produces an image like this for every source. Solid lines show master aperture, whilst dashed lines demark background annulus. Several of the fluxes for NGC 4559 have flags (flags are defined in Sect. 4). WISE 12 μm flux has “A” flag due to negative flux artefact in master aperture, whilst WISE 22 μm flux has “a” flag, due to a less pronounced version of the same feature. The Spitzer 3.6, 4.5, 5.8, and 8.0 μm fluxes have “N” flags (although these are borderline cases), as <40% of pixels in their sky annuli have coverage, so it is assumed that any background estimate will be unreliable (similarly, the lack of coverage in their master apertures would, independently, warrant “n” flags). Spitzer 24 μm and PACS 70, 100, and 160 μm flues have “n” flags, as <80% of pixels in their sky annuli have coverage, potentially reducing reliability of background estimate.