  A new method is developed for estimating photometric redshifts, using
realistic template SEDs, extending over four decades in wavelength (i.e from
0.05 $\mu m$ to 1 mm). The SEDs are constructed for four different spectral
types of galaxies (elliptical, spiral, irregular and starburst) and satisfy the
following characteristics: a). they are optimised to produce the observed
colours of galaxies at $z\sim 0$; b). incorporate the chemo-photometric
spectral evolution of galaxies of different types, in agreement with
observations; c). allow treatment of dust contribution and its evolution with
redshift, consistent with the spectral evolution model; d). include absorption
and re-emission of radiation by dust and hence, realistic estimates of the
far-infrared radiation; e). include correction for inter-galactic absorption by
Lyman continuum and Lyman forest.
  Using these template SEDs, the photometric redshifts are estimated to an
accuracy of $\Delta z = 0.11$. The degeneracy in the method and hence, the
redshifts and spectral types, are explored via Monte Carlo simulations. The
consistency of the technique is demonstrated by applying it on a UV selected
sample of HDF galaxies and comparing the statistical results with those from
other independent studies.
