Photometric accuracy for the Scan Map mode observations in the BS (70μm) band. Flux accuracy is the ratio of the measured flux density to the injected flux density. The perfect accuracy is highlighted with the yellow horizontal line at 1. The horizontal axis shows the different methods and aperture sizes used in the exercise. From left to right, the methods are the IDL aper routine with aperture sizes between 3 and 25 arcsec, with one-arcsecond steps; the AstroPy aperture_photometry routine using average background subtraction with aperture sizes of [4, 5, 6, 7, 8, 9, 10, 11, 12, 13, and 18] arcsec; the AstroPy aperture_photometry routine using median background subtraction using the same aperture sizes; the SUSSEXtractor flux determination (one value). The last method is the annularAperturePhotometry task in HIPE with aperture sizes similar to the AstroPy values. Figures for all observing modes and bands are found in Appendix A. HIPE DAOPhot and IDL gauss2dfit are not included because DAOPhot gives the same result as the annularAperturePhotometry given the same aperture size, while gauss2dfit was not used for flux density determination.