X-ray light curves do not obey the timescaling law [see, e.g., Figure 6 of @hac10k]. We are further able to discriminate these two parameters from multiwavelength light curve fitting. Thus, @hac15k [@hac16k] determined the WD masses within error of $\pm0.01~M_\sun$ by simultaneously reproducing the observed multiwavelength light curves for a number of novae.

@hac10k introduced the timescaling factor $f_{\rm s}$, which is the timescale ratio of a target nova against a template nova. Using this $f_{\rm s}$, we can compare various nova light curves in a quantitative way. They showed that, if a large part of the nova light/color curves overlap each other by properly squeezing/stretching their timescales, the absolute brightness ($M_V$) of the target nova is related to the absolute brightness ($M'_V$) of the other (template) nova by $M_V = M'_V + 2.5 \log f_{\rm s}$. This means that the time-stretched absolute light curves of the two novae overlap each other in the $(t/f_{\rm s})$-$(M_V-2.5 \log f_{\rm s})$ plane. They adopted V1668 Cyg and V1974 Cyg as template novae, of which the distances and extinctions are known. Using this property, @hac10k [@hac15k; @hac16k] determined the absolute magnitude $M_V$ for each free-free emission light curve of different WD mass and 