The unique feature of color variability in light emitting diode (LED) sources made of red, green, and blue LEDs (RGB-LEDs) allows the user to select the desired color point of the lamp. The highest color uniformity is obtained using LED clusters with high-density packaging. However, packaging density of LED arrays is limited by cost, available space, and particularly by thermal problems. This paper presents an investigation of the effects on color uniformity of illumination due to different cluster configurations and packaging density of RGB-LEDs. We present a photometric analysis and experimental results that show the performance that can be achieved with a number of different cluster configurations of LEDs.