Left: scatterplot of the continuum contrast vs. longitudinal flux density B_app,los for the plage field of view (FOV) shown in Fig. 1, obtained by removing the pores via a simple contrast threshold at a value of  − 0.18. Right: scatterplot of the continuum contrast vs. apparent longitudinal field strength B_app,los for the same plage FOV, obtained after degradation of the contrast and B_app,los by convolving with a Gaussian of FWHM and a Lorentzian of FWHM (mimicing straylight), while removing the pores with the same contrast threshold.