  We present new high-quality near-infrared photometry of 10 Galactic Globular
Clusters spanning a wide metallicity range (-2.12<[Fe/H]<-0.49): five clusters
belong to the Halo (namely, NGC288, NGC362, NGC6752, M15 and M30) and five
(namely, NGC6342, NGC6380, NGC6440, NGC6441 and NGC6624) to the Bulge. By
combining J, H and K observations with optical data, we constructed
Colour-Magnitude Diagrams in various planes (K,J-K), (K,V-K), (H,J-H), and
(H,V-H). A set of photometric indices (colours, magnitudes and slopes)
describing the location and the morphology of the Red Giant Branch (RGB) have
been measured. We have combined this new data set with those already published
by Ferraro et al.(2000) and Valenti et al. (2004), and here we present an
updated calibration of the various RGB indices in the 2MASS photometric system,
in terms of the cluster metallicity.
