This part is mainly based on leibundgut2000.
The supernovæ are observed in standard spectral filters (see Annexe A) in the visible one (filters UBVRI) and in infra-red (JHK). The repetition with regular intervals of measures to these filters allows the construction of a lightcurve. Figure 5.3 presents these lightcurves. The difference between the measures to the various filters makes it possible to build a curve of color. They are generally expressed of difference in magnitudes (B-v, V-r), which correspond to reports/ratios of flux. Initially, we describe the principal characteristics of these lightcurves in the course of time and in the various spectral filters deduced from close observations of supernovæ. Then we detail measurements of intrinsic luminosity. Lastly, we explain how it is possible, starting from the lightcurves in the various spectral bands, to build a curve of bolometric light.