The U.S. Department of Energy's CALiPER program has released Report 23: Photometric Testing of White-Tunable LED Luminaires, which is the first in a planned series of investigations on color-tunable LED luminaires. The main goal of the new study was to understand the amount of testing required to characterize a white-tunable LED lighting product. In this case, determining a sufficient protocol required more extensive testing than would be feasible for widespread use. Eight white-tunable luminaires were tested at dozens of points covering the range of color tuning (CCT) and dimming (luminous intensity).