  The presence of convective and turbulent motions, and the evolution of
magnetic fields give rise to existence of temperature fluctuations in stellar
atmospheres, active galactic nuclei and other cosmic objects. We observe the
time and surface averaged radiation fluxes from these objects. These fluxes
depend on both the mean temperature and averaged temperature fluctuations. The
usual photosphere models do not take into account the temperature fluctuations
and use only the distribution of the mean temperature into surface layers of
stars. We investigate how the temperature fluctuations change the spectra in
continuum assuming that the degree of fluctuations (the ratio of mean
temperature fluctuation to the mean temperature) is small. We suggest the
procedure of calculation of continuum spectra, which takes into account the
temperature fluctuations. As a first step one uses the usual model of a
photosphere without fluctuations. The observed spectrum is presented as a part
depending on mean temperature and the additional part proportional to quadratic
value of fluctuation degree. It is shown that for some forms of absorption
factor the additional part in Wien's region of spectrum can be evaluated
directly from observed spectrum. This part depends on the first and second
wavelength derivatives, which can be calculated numerically from the observed
spectrum. Our estimates show that the temperature dependence of absorption
factors is very important by calculation of continuum spectra corrections. As
the examples we present the estimates for a few stars from Pulkovo
spectrophotometric catalog and for the Sun. The influence of temperature
fluctuations on color indices of observed cosmic objects is also investigated.
