  We discuss all possible sources of uncertainties in theoretical values of the
photometric amplitudes and phases of B-type main sequence pulsators. These
observables are of particular importance because they contain information about
the mode geometry as well as about stellar physics. Here, we study effects of
various parameters coming both from theory of linear nonadiabatic oscillations
and from models of stellar atmospheres. In particular, we show effects of
chemical composition, opacities and, for the first time, effects of the NLTE
atmospheres.
