The Redshift Distribution of Distant Sources from Gravitational   Depletion in Clusters
  Gravitational lensing can be used to analyze the redshift distribution of faint galaxies. In particular the magnification bias modifies locally the galaxy number density of lensed sources observed in lensing clusters. This depletion area probes the redshift distribution of galaxies beyond B=25. In this proceeding I present this new tool to infer the redhsift distribution of faint galaxies. 
Y. Mellier (1,2) ((1) Iap (2) Obs. Paris DEMIRM)