Comparison of the ρ_c and filament mass estimates from the Plummer fits (open symbols) and the actual values of maximum line-of-sight densities and masses in the cloud model (solid squares). The error bars on the true densities correspond to the 1σ dispersion of the peak density values along the filament. In the mass estimates the solid squares correspond to the total mass within a projected distance of 0.1 pc of the filament. Model A: frames a) and d), model B: frames b) and e), model C: frames c) and f).