Detail of the continuum emission at 5 keV at different instants for the standard case. The orange/red colour-table represents the emissivity, as defined in Eq. (9). Dark red represents ϵ = 10¹³ erg s^-1 cm^-3 Hz^-1, a factor 10 stronger than yellow. The instants represented correspond, in order, to the final moments of the linear phase (t = 65 s), to the saturation phase/peak of emission (t = 75 s), to the early relaxation phase (t = 245 s), and to the later relaxation phase (t = 475 s). The scale at the bottom shows the corresponding pixel size for RHESSI and STIX both at the aphelion (~1 AU) and perihelion (~0.3 AU) of the spacecraft orbit. (An associated movie is available online.)