Originally Posted by SW15LS

Technically, 4100-4300k is the only DOT approved HID color temp. So technically higher are "not legal". Now, higher color temp LED headlights are legal...so its a grey area.

As to why some cars look bluer, it all has to do with how the projectors are designed. German cars tend to have projector designs that have sharp cutoffs, and those cutoffs create that twinkling blue/purple look to them.

LED headlights also have a color temp closer to 5000-5500K just by their nature.

Originally Posted by peteharvey

Because LED's are naturally cooler, they must add a phosphor coat on the LED dome to make the tints more neutral, ie warmer, hence the Zebralight flashlight at 6300K has a maximum output of 1100 lumens, while the neutral tinted 4400K has a max output slightly diminished to 1020 lumens due to the extra phosphor coat needed to make the cool tint warmer.

6300K & 1100 lumens: http://www.zebralight.com/SC600-Mk-I...ite_p_123.html
4400K & 1020 lumens: http://www.zebralight.com/SC600w-Mk-...ite_p_122.html

But be careful, because HID's are naturally more neutral in tint, so at 8000K, a HID has a sharp fall in brightness - about 50% down...
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