Visualization of the filtering (computed with λ = 0.7) zoomed in on the central part of the Musca 250 μm map. The level was chosen to emphasize low values. The left panel shows the filtered data and the right the unfiltered data. The positive effect of the filtering on the flux density data becomes obvious. The visualization performed on the singularity exponents (see Fig. 9) demonstrates the importance of filtering on filamentary structures, which are oflow fractal dimensions.