Fourier transform of the simulated star-forming region used in this paper (Appendix C) at 350 μm with a 24′′ resolution (Fig. 19, upper-left). The top panels show the Fourier amplitudes of separate components: the model sources, synthetic background, and noise (top left to right). The full image containing all the ingredients (and all spatial scales) is displayed in the following (middle-left) panel. The remaining panels (left to right, top to bottom) show the images of the single-scale decompositions of the simulated sky (cf. Fig. 2) with the scale sizes S_j annotated at the bottom of the panels. For the original images with 2048 × 2048  2′′ pixels, the panels present the Fourier amplitudes within the range of spatial frequencies from zero to one-fourth of the Nyquist frequency (0.25 arcsec^-1). For better visibility, the pixel values are somewhat limited in range; the color coding is linear.