Low frequency electronic ballasts are recommended by lamp manufacturers to drive the latest generation of ceramic, low wattage metal halide lamps. These ceramic lamps have superior color rendition and can potentially maintain that color over the life of the lamps when properly operated with electronic ballasts. Since color is dependent on proper lamp wattage, the electronic ballast must be able to maintain lamp wattage precisely at its rated point throughout the rated average life of the lamp. Low frequency electronic HID ballasts, such as the Philips Advance e-Vision® line, constantly measure and adjust the wattage, optimizing delivery of the ceramic lamps superior color properties. This makes ceramic metal halide operated by e-Vision® ballasts the premier choice for many applications previously illuminated by either tungsten halogen or incandescent sources, such as retail lighting. Operational improvements are gained as greater efficiency and cooler running electronic ballasts lead to energy savings. In addition, ballasts run quieter, weigh less and have smaller footprints.