LPT: Harmonize the tone of your headlights to prevent blinding oncoming drivers.

**TL;DR:** If your car's headlights are yellow, you're doing it wrong. All headlights should appear white to be in sync with the rest of the road, thus not attracting the attention of oncoming drivers. This is the reason why some headlights appear "brighter" than others even if they're not actually producing more lumens. Please calibrate your lights to help make the world a slightly better place, one road at a time. The life you save may be your own.<br><br>**Why?** Your pupils dilate in response to the amount of light you perceive in order to let the right amount of light into your eyes. If there's an imbalance between the road illuminance and the headlights, your pupils will dilate to accommodate the headlights, making the road darker when they pass. Yellow headlights appear brighter than they actually are because your brain is wired to respond to yellow as if it's a warning sign, thus attracting your attention and dilating your pupils unnecessarily. This is very dangerous at night because you may not see obstacles in the road in time to react after your pupils dilate for oncoming headlights. America, this especially applies to you.<br><br>**How?** In general, you should replace your factory bulbs with an LED or Laser equivalent that has a color temperature of 5700 - 6500K. This color temperature range is "neutral white" and is what the human eye is most accustomed to seeing in everyday life. Any color temperature above 6500K will have a blue tint, thus being perceived as "brighter" than it actually is. You should never go above 6500K. Your OEM headlights already have built-in coverings to block blue light to keep the tone white, but you typically do not have this covering with replacement bulbs.<br><br>**Which?** oring to CVLT, which is an online organization that tests headlights to provide an unbiased ranking of how well they perform, the best manufacturer of headlights is Osram. Osram headlights consistently produce better illumination of the road and less glare for oncoming drivers. This may not always be the case in the future but is currently true today. Philips also makes excellent headlights.<br><br>**Caveat:** In some jurisdictions, there may be laws restricting the use of non-OEM headlights. I have not personally researched the details of these laws but be aware of them nonetheless. If you get a ticket from a cop for having better headlights than your OEM, tell him I said hi and "you're welcome" from the bottom of my heart.