We present a new set of secondary standard stars for the u'g'r'i'z' photometric system that has been established in selected open and globular star clusters. These standards are calibrated to the original standard system defined by Smith et al. with an accuracy of 1% or better, extend as faint as r'~20, and are concentrated in small regions of the sky. As a result, they can serve as viable calibrators of photometry obtained on some of the large-aperture, high-demand telescopes that employ the u'g'r'i'z' filter set.

Cone search capability for table J/AJ/134/1890/table5 (Secondary standards in star clusters NGC 2682, NGC 5272, NGC 6205, NGC 6341, NGC 6791, NGC 6838)