  We describe the first results from our project aimed at large-scale
calculations of NLTE abundance corrections for important astrophysical atoms
and ions. In this paper, the focus is on Fe which is a proxy of stellar
metallicity and is commonly used to derive effective temperature and gravity.
We present a small grid of NLTE abundance corrections for Fe I lines and
discuss how NLTE effects influence determination of effective temperature,
surface gravity, and metallicity for late-type stars.
