  We present a new interpretation of long premaximum halts of nova outbursts.
For V723 Cas (Nova Cas 1995) and V463 Sct (Nova Sct 2000), we have reproduced
light curves, excluding the brightness maxima, starting from the long
premaximum halt through the late decay phase of the outbursts using a
steady-state optically thick wind model. When the hydrogen-rich envelope of the
white dwarf (WD) is massive enough, the star expands to \sim 100 R_\sun or over
and its surface temperature decreases to below 7000 K. At this supergiant
mimicry stage, the changes in both the photospheric radius and the temperature
are small against the large increase in the envelope mass. These changes cause
a saturation in visual magnitude that lasts a long time before it begins to
decline. This saturation is known as the premaximum halt of a classical nova
outburst. The visual magnitude during the saturation is close to the bolometric
magnitude, which is an upper limit for a given WD mass. Since the WD masses are
estimated to be 0.59 M_\sun for V723 Cas and 1.1 M_\sun for V463 Sct by fitting
the decline rate of nova light curves, we can determine the absolute magnitude
of premaximum halts. It is a refined Eddington luminosity. Thus, the premaximum
halt of a nova works as a standard candle.
