The luminosity function of cluster galaxies II. Data reduction procedures applied to the cluster Abell 496

We initiated a large project aimed to estimate the Luminosity Function of g alaxies in clusters and to evaluate its relation to cluster morphology. Wit h this paper we deem necessary to outline the general procedures of the dat a reduction and details of the data analysis. The cluster sample includes t he brightest southern ROSAT all-sky survey clusters with z < 0.1. These hav e been observed in three colours g, r, i, and mapped up to a few core radii using a mosaic of CCD frames. E/S0 galaxies in the cluster core are single d out both by morphology (for the brightest galaxies), and by colour. The d etails of the data reduction procedure are illustrated via the analysis of the cluster Abell 496, which has been used as a pilot cluster for the whole program. The related photometric catalogue consists of 2355 objects. The l imiting magnitudes (the reference Surface Brightness is given in parenthesi s) in the various colours are respectively g(25.5) = 24.14. r(25.5) = 24.46 , i(25.0) = 23.75. These correspond to the limiting absolute magnitudes -12 .28, -11.96 and -12.67 (H-0 = 50 km/s/Mpc).