  We present a high-resolution spectroscopic analysis of two samples of evolved
stars selected in the field and in the intermediate-age open cluster IC 4651,
for which detailed measurements of chemical composition were made in the last
few years. Applying the Gray's method based on ratios of line depths, we
determine the effective temperature and compare our results with previous ones
obtained by means of the curves of growth of iron lines. The knowledge of the
temperature enables us to estimate other fundamental stellar parameters, such
as color excess, age, and mass.
