On Mon, 6 Oct 2008, Eran Burstain wrote: > Hi ! > How can I convert geocentric ECEF coordinates to UTM and vice versa ? Something like cs2cs +proj=geocent +ellps=XXXX +to +proj=utm +zone=XX +ellps=XXXX should do it. You might want some datum transformation parameters too (+towgs84=X,X,X) depending on your application. Paul