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We have obtained broad-band near-infrared photometry for seven Galactic starclusters (M92, M15, M13, M5, NGC1851, M71 and NGC6791) using the WIRCamwide-field imager on the Canada-France-Hawaii Telescope, supplemented by imagesof NGC1851 taken with HAWK-I on the VLT. In addition, 2MASS observations of the[Fe/H] ~ 0.0 open cluster M67 were added to the cluster database. From theresultant (V-J)-V and (V-Ks)-V colour-magnitude diagrams (CMDs), fiducialsequences spanning the range in metallicity, -2.4 < [Fe/H] < +0.3, have beendefined which extend (for most clusters) from the tip of the red-giant branch(RGB) to ~ 2.5 magnitudes below the main-sequence turnoff. These fiducialsprovide a valuable set of empirical isochrones for the interpretation ofstellar population data in the 2MASS system. We also compare our newly derivedCMDs to Victoria isochrones that have been transformed to the observed planeusing recent empirical and theoretical colour-Teff relations. The models areable to reproduce the entire CMDs of clusters more metal rich than [Fe/H] ~-1.4 quite well, on the assumption of the same reddenings and distance modulithat yield good fits of the same isochrones to Johnson-Cousins BV(RI)Cphotometry. However, the predicted giant branches become systematically redderthan the observed RGBs as the cluster metallicity decreases. Possibleexplanations for these discrepancies are discussed.

Fiducial Stellar Population Sequences for the VJKs Photometric System