The usefulness of 2MASS JHKs photometry for open cluster studies

2mass jhks data are used to infer the reddening and distance of open clusters for which limited optical data are available. intrinsic zams color-color and color-magnitude relations are derived with reference to existing calibrations, standard stars, three uniformly-reddened clusters: stock 16, ngc 2362, and ngc 2281, and unreddened hyades dwarfs. the method of inferring interstellar reddening and distance for sparsely-populated open clusters is applied to berkeley 44, turner 1, and collinder 419, for which existing results conflict with those inferred from jhks data. the last two clusters are of special interest: turner 1 because it hosts the galaxy's longest-period classical cepheid, and collinder 419 because it lies in the cygnus x complex.