We present new high-quality near-infrared photometry of 10 Galactic Globular Clusters spanning a wide metallicity range ( -2.12 { \leq } { [ Fe / H ] } { \leq } -0.49 ) : five clusters belong to the Halo ( namely , NGC 288 , NGC 362 , NGC 6752 , M 15 and M 30 ) and five ( namely , NGC 6342 , NGC 6380 , NGC 6440 , NGC 6441 and NGC 6624 ) 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 ( ) and ( ) , and here we present an updated calibration of the various RGB indices in the 2MASS photometric system , in terms of the cluster metallicity .