Synthetic SN Ia spectra of consistent ALImI-models (SN Ia models based on an accelerated lambda iteration procedure for the mutual interaction of strong spectral lines, cf. Pauldrach et al. 2014) using the original (red curve) and the new treatment (green curve) of the Feautrier method in the first iteration cycle (shown is the flux after the first iteration that uses the detailed solution). Although the two models are not strictly comparable since the occupation numbers, the ionization, and the temperature structure adjust differently because of the differences of the Feautrier schemes applied, it is readily seen that the behavior of the flux is different particularly for those wavelengths that are dominated by strong lines. For comparison, an equivalent blackbody spectrum (black curve) corresponding to the effective temperature of the atmosphere (T_eff = 12 540 K) and the spectrum resulting from a formal solution without lines (blue curve) are also shown, demonstrating the very different slopes these two curves exhibit even in the wavelength range redward of 4000 Å where the supernova ejecta are much less dominated by spectral lines. (Blueward of 3000 Å the flux is of course blocked and strongly attenuated by spectral lines; flux conservation results in enhanced emission redward of 3000 Å compared to a black body.)