2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/14451We discuss a method aiming to use photometric redshifts in lensing clusters to access the population of distant background sources. The amplification provided by gravitational lensing allows to calibrate photometric redshifts 1 to 3 magnitudes deeper with respect to field studies. We present and discuss some results obtained with this procedure on extensively studied clusters, as well as the future issues of this project.6 pages, 4 figures, Conference Proceedings of the "Photometric Redshifts and High Redshift Galaxies", April 28-30, 1999, PasadenaAstrophysicstext