The variability of human observers and differences in the cone photoreceptor sensitivities are important to understand and quantify in the context of Color Science research. Differences in human cone sensitivity may cause two observers to see different colors on the same display. Technicolor SA built a prototype instrument that allows classification of an observer with normal color vision into a small number of color vision categories. The instrument is used in color critical applications for displaying colors to human observers. To facilitate Color Science research, an Observer Calibrator is being designed and built. This instrument is modeled on one developed at Technicolor, but with improvements including providing higher luminance levels to the observers, a more robust MATLAB computer interface, two sets of individually controlled LED primaries, and the potential for interchangeable optical front ends to present the color stimuli to observers. The new prototype is lightweight, inexpensive, stable, and easy to calibrate and use. Human observers can view the difference between two displayed colors, or match one existing color by adjusting one LED primary set. The use of the new prototype will create opportunities for further color science research and will provide an improved experiment experience for participating observers.