Flattening for the component ℱ_ƛ (Sect. 3.3) for ℐ_ƛ ≡ 𝒟_13″ from Eq. (8). The top row shows the original ℐ_ƛ, the background-subtracted ℱ_ƛ from Eq. (23), and the standard deviations 𝒱_ƛ from Eq. (24). The bottom row shows the flattening image ℛ_ƛ, the flat filaments ℱ_ƛD from Eq. (27) and its standard deviations which are much flatter (outside the filament) across the image. Square-root color mapping, except in the right panels, which show logarithmic mapping.