Histograms of derived crest-averaged properties (half-power diameter, hd, in panel a; filament contrast, C⁰, in panel b; background-subtracted central column density, , in panel c) in measurement tests using a population of Gaussian mock filaments. The vertical dashed lines in panels a and b indicate the fixed input properties of the mock filaments: FWHM width (W = 0.1 pc) and column density contrast (C⁰ = 1). In panel c, the black and green histograms show the distribution of input and derived background-subtracted column densities averaged along the filament crests, respectively.