Photometric catalog of nearby globular clusters. II. A large homogeneous (V,I) color-magnitude diagram data-base

In this paper we present the second and final part of a large and photometrically homogeneous CCD color-magnitude diagram (CMD) data base, comprising 52 nearby Galactic globular clusters (GGC) imaged in the V and I bands. The catalog has been collected using only two telescopes (one for each hemisphere). The observed clusters represent 75% of the known Galactic globulars with (m-M)_V<= 16.15 mag, cover most of the globular cluster metallicity range (-2.2 <= [Fe/H]<= -0.4), and span Galactocentric distances from ~ 1.2 to ~ 18.5 kpc. In particular, here we present the CMDs for the 13 GGCs observed in the Northern hemisphere. The remaining 39 Southern hemisphere clusters of the catalog have been presented in a companion paper (Rosenberg et al. \cite{rosenberg00}). We present the first CCD color magnitude diagram for NGC 6779 (M 56). All the CMDs extend from at least ~ 2 magnitudes below the turn-off (i.e. V_lim>=22) to the tip of the red giant branch. The calibration has been done using a large number of standard stars, and the absolute calibration is reliable to a ~ 0.02 mag level in both filters. This catalog, because of its homogeneity, is expected to represent a useful data base for the measurement of the main absolute and relative parameters characterizing the CMD of GGCs. Based on observations made with the 1~m Jacobus Kapteyn Telescope operated on the island of La Palma by the ING in the Spanish Observatorio del Roque de Los Muchachos of the Instituto de Astrofìsica de Canarias.