  By a proper arrangement of a digital holography setup, that combines off-axis
geometry with phase-shifting recording conditions, it is possible to reach the
theoretical shot noise limit, in real-time experiments.We studied this limit,
and we show that it corresponds to 1 photo-electron per pixel within the whole
frame sequence that is used to reconstruct the holographic image. We also show
that Monte Carlo noise synthesis onto holograms measured at high illumination
levels enables accurate representation of the experimental holograms measured
at very weak illumination levels. An experimental validation of these results
is done.
