I shall describe the CCD imaging of globular cluster program, active since 2004, at Indian Astronomical Observatory (IAO), at the Hymalayas, aimed to make a variable star census of each cluster under study and to discuss some mean physical parameters, such as [Fe/H] and distance, as determined from the light curve Fourier decomposition technique of the cluster RR Lyrae stars. I will briefly describe the technique. The caveats of the Fourier decomposition approach shall be recounted. In the process new variables of assorted types have been discovered as well as presumed variables that are not. Of particular relevance are the Blazhko RR Lyrae and the SX Phe stars. The overall results from a family of clusters lead to an independent estimation of the metallicity dependence of the Horizontal Branch luminosity level, the well-known [Fe/H] -Mv(HB) relationship. This relationship plays an important role in the RR Lyraes distance scale. Specific results for 2 or 3 clusters will be addressed.