HID Kit installations are all the rage these days, most if not all of the people are misguided by false marketing.
This article will attempt to clear some of the fog surrounding HID Kits and HID Technology in general.
Common misconception:
“Projectors are useless without hid , with normal bulbs u will face many problems in vision”.
Actuality:
That is far from true, projectors have far better output even with halogen bulbs, take the camry for example it comes with halogen projectors and light output is way better compared to a reflector housing.
Projectors come in two different types; (1)Halogen (2) HID. Now aftermarket projectors that are sold, 99.9% of them are Halogen projectors, but as everyone does not know this, they put HID’s in the Halogen Projectors and the output is ridiculous to say the least. The reason is because the focal point of the halogen bulb is different from the HID bulb.
Misconception:
“Why Install Projectors in The First Place??.. Why Not Only Install HID’s In Stock HeadLamps??. They Give More Light Than Projectors..”
Actuality:
That is also false, HID in reflector housings gives the worst output.The glare you get is blinding to say the least. Most of the folks put HID in halogen projectors and then complain that the output is worse.
Here is the output of light in descending order: HID Projector>Halogen Projector>Reflector Housing.
Now let me show you comparison pictures of outputs in different applications.
Real HID Projector Output: No light above the cutoff line; 
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Another image of a real HID projector, this is a RHD projector, hence the higher side is on the left; 
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Halogen Projector with halogen bulb, Output: No light above the cutoff line;
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Halogen Projector with HID bulb, Output; This is a common mistake, notice the Light has dispersed. Light has escaped above the cutoff line. Oncoming traffic gets a little glare in their eyes. 
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HID in reflector Housing: By far the worst output.There is no cutoff line.That’s why the oncoming traffic gets glare in their eyes. 
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5.jpeg [ 23.6 KiB | Viewed 1256 times ]
More Pointers:1. If your car came with Halogens from the factory, Halogens will give you the best visibility(in your stock headlight) no matter what anyone says.
2. The purpose of the high beam is to put light in the distance.When your high beam reflector is not meant for an HID then how in the world is the HID going to be effective. Also, HID’s take time to come up to full intensity(usually 5-15 seconds) and that defeats the purpose of a high beam.
3. Light output(measured in lumen) is inversely proportional to the color temperature(measured in kelvins or K) so, the most light you would get will be out of 4300K(Same color temperature as daylight). Beyond 6000K its just plain useless.
One thing to note the reason that the “Blue” HID lights seem to be brighter is because of the simple reason that the human eye is very sensitive to blue light which is the very reason it dazzles our eyes and gives the illusion that it is brighter which in fact is totally false.
After-market ProjectorsAll of the projectors headlamps available at car accessory shops are Halogen, most of the people do not know this, and when they buy them and put an HID Kit in the projectors, they start complaining of the lack of visibility.
A simple way of identifying a halogen projector is that it simply uses any of the halogen bulb types for example like H11,H3 etc.
Real HID Projectors use HID bulbs like D2S,D1S etc.
Cars with HID reflector housings(from the factory):
Now before you go all flaming on me that there are some cars out their like the 2nd Gen Toyota Prius, 9th Gen Toyota Corolla(in some markets), 8th Gen Civic Mugen RR, etc, that have HID’s from the factory even though they have a reflector housing; Let me explain that as well;
The cars above all have one thing in common, their reflector housings were designed from the ground up to be used with an HID bulb. These reflectors are diamond cut for more precise cutoff to reduce most of the glare and use a bulb known as D2R (R for Reflector). Half the bulb glass is covered with paint to reduce the the glare even further.
Now you all be the judge.I have made the mistake of putting HID’s in reflector housings but after doing extensive research I have come to the conclusion that HID should only be used in HID Projectors Only.
