WST statistics of Planck radiance map (left column) and DHIGLS N_H I map (right column) compared to those computed using the optical map with matched beam widths. The x-axis describes the coherence scale j₂. The structure scale is color-coded by j₁. Only j₂ > j₁ ≥ 1 terms are shown because j₁ = 0 structures are significantly smaller than the beams and j₂ ≤ j₁ terms are dependent on the wavelets. In general, s₂₂ and s₂₁ of Planck follow similar trends with those of optical, except for s₂₂ at large coherence scales. However, H I shows deviation from the optical, which could be caused by different processing of H I data and possibly indicate the decoupling between gas and dust.