def38
Platinum Member
The human eye sweet spot for color is 4300K, the color temperature chosen for OE automotive HID headlamps. Anything much above that starts to get into the UV spectrum, lowers the reflective light coming back from the object of interest. Remember, all light from deer, road signs, potholes and other road stuff is reflected. Therefore the reflected light must make a round trip, twice the distance from the object or target. Light is reduced by the square of the distance. Therefore, you want maximum light for optimized reflection. That would be 4300K. Much lower than that temperature and your now approaching the IR band where we see poorly and IR doesn't reflect well. HIDs offer the best light temperature and light intensity control inasmuch as the lamp color and intensity is determined by noble gasses and metal salts, mostly sodium and iodide. Also, projector HID headlamp designs incorporate a metal mask that controls spillover thereby protecting oncoming drivers from the dazzle of bright, oncoming headlamps.