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