  We have determined spectroscopic ages of elliptical galaxies in the Virgo
cluster using spectra of very high signal-to-noise ratio (S/N/A > 100). We
observed 8 galaxies with the Subaru Telescope and have combined this sample
with 6 galaxies previously observed with the WHT. To determine their ages we
have used a new method based on the Hgamma_sigma age indicator, which is
virtually independent of the effects of metallicity. Apart from ages we have
estimated abundances of various elements. In this paper we present the
observations, the data reduction and the reliability of the Hgamma_sigma
method. The results of this investigation are presented in a companion paper
(Yamada et al. 2006).
