(a) Example of a host galaxy consisting of an exponential disk with two spiral arms and a spherical bulge. Details on the adopted parameters are reported in the text. (b) Model of a host galaxy, made of an exponential disk, a spherical bulge, and two spiral arms, populated with Sérsic stellar clumps. Details on the adopted parameters are reported in the text. The galaxy center coincides with the center of the field of view. (c) RGB color image of the same source. Here, we assume the bulge is 1 Gyr old, while the disk is 500 Myr old. For the stellar clumps, their ages span in the range 1–500 Myr. In this case, the red, green, and blue channels correspond to effective wavelengths λ_e = 5, 3, and 2 μm, respectively (0.70, 0.42 and 0.28 μm, rest-frame, taking into account an assumed redshift z = 6.145). These images have an angular resolution of 0.25 mas/pix, which at a z ~ 6 corresponds to a physical scale of approximately 1 pc per pixel. As a result, our clumps, all of which have sizes between 1 and 10 pc, are resolved in the high-resolution images.