Parameter Δβ as a function of ΔT for the four kernel types, using an edge-on galaxy with the dust profile b. (z_d = 1 kpc, S/N = 10⁴). For a given kernel type, there are 21 data points, each of which correspond to a measurement on a single pixel along the galaxy profile. The spread thus represents the systematic error on the β−T measurement for this kernel type. Error bars on both axes at the centre indicate the statistical errors on β and T obtained from the χ²-fitting routine.