Galaxy number counts in the field of Abell 2163. The black dots correspond to r′ magnitudes. The diamonds are the r′ number counts in the CFHTLS deep field D1. In both fields, only galaxies with CLASS_STAR  < 0.8 are kept. The excess at bright magnitudes in A2163 represents the cluster galaxies. The limiting magnitude is consistent with what is expected for compact objects measured at the 5σ level.