Photometric system used to generate the mock observation for the actively star-forming simulated galaxies of Sect. 4.1. The lower x-axis shows the keyword name of the band-pass transmission while the upper x-axis shows the corresponding wavelength in angstroms. Transmissions are expressed in terms of photons and the dashed lines mark the position of the pivot wavelength for each band-pass filter. We note that this is just a possible set-up specific to the case of the mock galaxy of Sect. 4.1. It represents only a sub-set of the band-pass transmissions available in the GalaPy database.