[kns]

Several members have installed HID headlight conversion kits and others have expressed interest in doing so.

There are pros and cons for use of HID headlights. Among the pros are higher light output, "whiter" light and lower power consumption. Among the cons are that the narrow spectral lines of HID lamps can distort color perception, ie, the ability to differentiate one color from another. And, according to NHTSA and many researchers, the higher luminance of HID headlights can cause glare and temporary night blindness. This is not surprising since our eyes rapidly adapt to an increase in brightness but take minutes to adjust to reduced brightness.

European regulations require HID headlights to incorporate lens cleaners (to reduce glare) and automatic leveling (to maintain proper light distribution.) The US allows manufacturers and importers to self-certify their products. Conversion kits may or may not include these desirable safety features.

Most importantly, from what I have read, it appears that NHTSA has concluded that no HID conversion kit can satisfy Federal Motor Vehicle Safety Standards (FMVSS) for on-road use.

There are many products on the market that are not necessarily good for us or for those around us. Just because it is possible to install an HID headlight conversion kit doesn't mean that it is a good idea to do so. Members considering a conversion kit should be aware of the potential impact on other drivers as well as the electrical, visual and explosive hazards that accompany HID lamps.

The following may be useful to members seeking additional information about HID headlights.
https://en.wikipedia.org/wiki/High-intensity_discharge_lamp (See especially the section on applications.)
https://en.wikipedia.org/wiki/Headlamp
http://www.aa1car.com/library/hid_headlamps.htm (Includes info on NHTSA findings on conversion kits.)
http://www.sigmaautomotive.com/HID/x5kit.php (Includes a NHTSA review of a conversion kit and comments on conversion kits in general.)
http://isearch.nhtsa.gov/files/kim.ztv.html (The last sentence of the third paragraph expresses NHTSA's view on conversion kits. FMVSS are the Federal Motor Vehicle Safety Standards which sets a maximum limit on headlight luminance.)

And the following may be useful to members seeking to understand the differences between HID and Halogen lamps.
https://en.wikipedia.org/wiki/Metal_halide_lamp
https://en.wikipedia.org/wiki/Halogen_lamp

KNS

 

[Steverino]

Thanks for posting this info, KNS. I have no interest in doing HIDs, but as you say, others have.

 

[saghost]

The Volt's OEM bulbs are something new - a conventional filament in an IR treated spherical bulb, which reflects back all of the low frequencies, causing the bulb to run hotter (and thus both brighter and whiter.) It's supposed to have about 2/3rds the benefits of HID in terms of brightness/efficiency, with none of the drawbacks and costs.

Personally, I'd rather go night vision:
http://www.opticsplanet.com/flir-pathfindir-30-hertz-nightvision-thermal-ntsc-camera.html

 

[DonC]

Very interesting post. Thanks for posting. Also thanks to saghost, didn't know that about the Volt's headlights. On the night vision, someday we'll see these technological advancements, assuming that the safety standards eventually get updated.

 

[AZ-Volt]

My 2 cents...

I used to be involved in doing HID retrofits for others and myself on a regular basis. In my case it was always HID designed projectors installed into factory light housings that did not have either projectors at all or HID quality projectors. Having said that I have found that the Volt stock projectors are about as well suited for HID conversion as any non HID projector I have ever seen. Actually better than some projectors that were designed for HIDs in the first place. I suspect they were initially designed for this use by GM (guessing of course). Furthermore most factory non HID and even an unusually high number of HID projectors still use a seperate element for high beams as opposed to the flip up baffle. The Volt does have the high beam baffle which is, again, ideal for HID conversion. The cutoff line on the Volt, post HID conversion, is excellent and if the headlight level is adjusted properly will absolutely not glare oncoming traffic. I believe this is probably the single most recommended upgrade to the Volt that I can think of. The difference in lighting look and utility is simply fantastic and no where near any kind of warranty violation if done properly. I recently compared photos of my Volts low beam cutoff and highbeam patterns and they are VERY close to the stock patterns on a former Honda S2000 we once owned. At that time the S2000 projectors were considered some of the best though since then there are many better choices for retro fits. To each their own but if you do mods this has to be at the top of your list!

 

[larry4pyro]

The main reason most people have changed to HIDs is the stock headlights in the Volt produce below average illumination, HIDs improve this situation significantly. This change is not approved in many states, however I suspect most owners, like myself, are willing to accept the risk. I believe the Volt is safer with HIDs, simply because you are able to see in areas where the OEM bulbs did not provide adequate illumination.

I agree with AZ-Volt on the beam pattern after the change to HIDs. That is, the pattern appears to be exactly the same, only the light intensity in all areas appear to be uniformly brighter, so I also suspect these hand lamps were originally designed with HIDs in mind.

 

[AySz88]

I would like to request that those considering this please also take into account their effect when they happen to shine into other drivers' eyes (on hills, etc.). Sure, things are brighter, but personally, I think the detriment to the other drivers' vision in those situations wouldn't be worth it to me.

[edit] larry4pyro - Out of curiosity, how does that jive with what saghost said about the OEM bulb being "[supposedly] 2/3rds the benefits of HID in terms of brightness/efficiency, with none of the drawbacks and costs"?

 

[C-Kwik]

Thanks for starting this kns. I didn't expect the other thread to have such responses.

I'll start my post by reposting the links I put in the other thread:

http://www.danielsternlighting.com/tech/bulbs/Hid/conversions/conversions.html

http://www.danielsternlighting.com/tech/bulbs/Hid/disadvantages/disadvantages.html

And now I'll address the responses to my posts in the other thread here (the ones I didn't respond to already anyways):

Those who can do, do. Those who can't do, teach.

Defensive much? Ultimately, this statement is irrelevant. So I'll leave it at that.

I have a really nice HID set up from Morimoto, 35 watt, 5000K and the bottom line is that I can see much better at night with those lights than I could with the stock set up. Don't go trying to tell someone that has done this modification, that we cannot. I don't really care about physics, patterns or any other mumbo jumbo. I care about real time results. My results are really good, much better than stock. Now are there some cheap HID's out there that do not work as good, absolutely. But for those of us that have real time results that are good, don't try to tell us, that they are not, and we only think they are. I also have never had someone flash their lights at me, so I know I am not blinding anyone.

I never said you couldn't do it. I merely said the beam pattern will be altered. Nothing more, nothing less. I don't propose to know if the Volt's projectors will provide a better beam pattern with any of the myriad of aftermarket conversion kits than the OE bulbs. Its unlikely, but again, do with the information what you want. I will however note that your observations can easily deceive you. The perception is that the brighter everything is is better. In some cases, this is true. Even while driving. But consider that the human eyes are not perfect detectors. They have areas that are able to see better than others. Your cones and rods are not evenly distributed. Things light lighting up the foreground too much can affect your distance vision because your pupils contract. We use both rods and cones while driving. Too much lighting can drastically affect that balance and make it hard to see areas where there are no headlights. Search out some studies on lighting and pedestrians. There are some interesting reasons why pedestrians are hard to see at night. And this especially becomes a problem if they are in the areas that are not lit by your headlights. Brightening the area that they are not in doesn't help matters as you affect how well the rods can perform (which is the part that most helps you detect them in low light).

As for high or low quality HID, read the links I posted. There is a fundamental different in the shape and distribution of the light source. Since the reflector and lens are static components of the system, the shape and intensity distribution of the light beam will be affected. How good the quality of the HID system you buy is has no effect on this.

I realize you say you are only trying to inform, however you may also be causing someone who could benefit from this modification to not do it, based on the theory that it does not function as desired, when in real time it does if you choose a good company and kit.

On the other hand, I may be causing someone not to install a poor lighting system in their car. The reality is I have no idea how good or bad the lighting ends up to be. And frankly, I doubt you do either. Subjective analysis may be good enough for you, but the lighting standards are based on a compromise of many many problems that are associated with automotive lighting and nighttime visibility. Under specific circumstances, the light output you observe may indeed be better. But without a comprehensive objective analysis, how would you know?

The links I posted are quite basic. I can probably source out some peer-reviewed articles in engineering and biological journals, but you probably wouldn't have access to them without having to pay for them. The links are however, a great starting point for anyone wishing to seek more information. I'd venture to guess you are not one of these people. So feel free to move on. I'm not here to be judgmental. You have no reason to have to justify your decision to me. You can put them on just because you like how your car looks with them on for all I care.

I guess I don't understand, you said halogen housing are not made for HID's. I agree.
These housing we have sure seem like they are meant for HID's with the cut-off and pattern.

So are you just not liking HID's at all??

On the contrary. I was rather disappointed when I saw the Volt didn't have them as an option. Personally, I just prefer not to alter my beam pattern. They are designed a certain way for very specific reasons.

Does Stern compare halogens vs HIDs where the halogen is in a projector, or just when the HID is used in a halogen-designed reflector? Because unless I'm mistaken, there's no reflector optics for the headlights in the housing, only a projector 'eyeball', which makes historical comparisons of the two somewhat irrelevant.

Here's what he has to say:

"In many lamps, especially the projector types, the cutoff will remain the same regardless of what light source is behind it. Halogen bulb, HID capsule, cigarette lighter, firefly, hold it up to the sun—whatever. That's because of the way a projector lamp works. The cutoff is simply the projected image of a piece of metal running side-to-side behind the lens. Where the optics come in is in distributing the light under the cutoff. And, as with all other automotive lamps (and, in fact, all optical instruments), the optics are calculated based not just on where the light source is within the lamp (focal length) but also the specific photometric characteristics of the light source...which parts of it are brighter, which parts of it are darker, where the boundaries of the light source are, whether the boundaries are sharp or fuzzy, the shape of the light source, and so forth."

And to my knowledge, all projectors still use a reflector. It would probably be a bad idea not to. If you used a light absorbing surface behind the bulb, you would effectively lose half the light that is available from the bulb. A white backing might help recover some of that light, but it would diffuse a great deal and you would lose a lot of control over where that light ends up since that diffused light would no scatter in many directions rather than reflect the actual image produced by the light source.

 

[C-Kwik]

My 2 cents...

I used to be involved in doing HID retrofits for others and myself on a regular basis. In my case it was always HID designed projectors installed into factory light housings that did not have either projectors at all or HID quality projectors. Having said that I have found that the Volt stock projectors are about as well suited for HID conversion as any non HID projector I have ever seen. Actually better than some projectors that were designed for HIDs in the first place. I suspect they were initially designed for this use by GM (guessing of course). Furthermore most factory non HID and even an unusually high number of HID projectors still use a seperate element for high beams as opposed to the flip up baffle. The Volt does have the high beam baffle which is, again, ideal for HID conversion. The cutoff line on the Volt, post HID conversion, is excellent and if the headlight level is adjusted properly will absolutely not glare oncoming traffic. I believe this is probably the single most recommended upgrade to the Volt that I can think of. The difference in lighting look and utility is simply fantastic and no where near any kind of warranty violation if done properly. I recently compared photos of my Volts low beam cutoff and highbeam patterns and they are VERY close to the stock patterns on a former Honda S2000 we once owned. At that time the S2000 projectors were considered some of the best though since then there are many better choices for retro fits. To each their own but if you do mods this has to be at the top of your list!

Can you provide more objective information? Like how the beam pattern is projected onto the ground? I believe a topographical map of it with lighting intensity as the elevations is most typical. As I said earlier, there is a lot more to automotive lighting than how much better you think you see. I suspect most people try to judge this by aiming their lights at a wall. Some may also even aim it down a flat road. Neither gives you a comprehensive picture of how well it performs in all situations. Lighting is to some extent about seeing the road. But its also how well we see hazards on them. Different intensities and color can affect the contrast between an hazard and the background. If the contrast is low, we tend to see the hazard much later.

 

[artsci]

My judgments about the HIDs I installed on my Volt are based solely on the improvements in revealing the road ahead, particularly potential hazards such as dear or fallen tree branches. My daily commute includes a two mile stretch on a very narrow, curvy road on which hazards of this kind are quite common. The HIDs light up an extra 100 yards or so of the road ahead and also light up much better both sides of the road, where dear might be poised to pounce. That's a very important extra margin of safety.

As for blinding on oncoming cars, I never get flashed, which suggests this is not a problem. IMHO HIDs are a very good safety investment.

 

[C-Kwik]

The main reason most people have changed to HIDs is the stock headlights in the Volt produce below average illumination, HIDs improve this situation significantly. This change is not approved in many states, however I suspect most owners, like myself, are willing to accept the risk. I believe the Volt is safer with HIDs, simply because you are able to see in areas where the OEM bulbs did not provide adequate illumination.

I agree with AZ-Volt on the beam pattern after the change to HIDs. That is, the pattern appears to be exactly the same, only the light intensity in all areas appear to be uniformly brighter, so I also suspect these hand lamps were originally designed with HIDs in mind.

The benefit of HID lighting is simply the amount of light we get for the wattage consumed. In current systems, we can get up to 3 times more lumens than halogens. And while that can be advantageous, the problem lies in what actually happens to the extra light. The reality is the beam pattern will change. There is no denying this. Its simply optical physics. Think of it this way. Look in a curvy mirror at a fun house. It distorts the image, but ultimately it distorts the image of you. No look at someone else through that same mirror. I can guarantee that you will not see the same image that you saw when you were standing in front of it. The nature of optics is that you see a reflection of what is actually in front of the reflector, perhaps distorted by the reflector. So if you change the shape and light distribution of the source image, then then the resultant image will be changed accordingly.

That said, if the arc is oriented closely to the way the filament sits, then you might see an image that somewhat resembles the filament beam. But the shape of a filament and the distribution of light intensity from it is different than from an arc capsule. The beam pattern will change accordingly.

 

[saghost]

I would like to request that those considering this please also take into account their effect when they happen to shine into other drivers' eyes (on hills, etc.). Sure, things are brighter, but personally, I think the detriment to the other drivers' vision in those situations wouldn't be worth it to me.

[edit] larry4pyro - Out of curiosity, how does that jive with what saghost said about the OEM bulb being "[supposedly] 2/3rds the benefits of HID in terms of brightness/efficiency, with none of the drawbacks and costs"?

You'll have to talk to Larry about the "below average illumination" part - I think the Volt's headlights are noticeably better than most I've driven with - especially on high beam (I do wish I could see more around corners in low beam - but those are the areas they blocked out for protecting other drivers, so I guess I'll live with it.)

As for what I was talking about, the technology is called HIR:

http://store.candlepower.com/9011hir.html

http://www.danielsternlighting.com/tech/bulbs/bulb_types/bulb_types.html

http://en.wikipedia.org/wiki/Headlamp#Halogen_infrared_reflective_.28HIR.29

As you can see, the typical (I think?) halogens they chose for an example are 1700/1000 (high/low) lumen - the HIR are 2530/1800, and OEM HID are in the 2800-3300 lumen range (I think that's high only - presumably less behind the shield for low, but I'm not sure.)

So the HIR gives you most of the brightness of the HID, and without using more power than halogen, so it gives you some of the efficiency advantages. It's still a conventional filament, though, so it doesn't have the regulatory issues, color oddness, and glare mentioned in this thread, or the potential to drop surges into your electronics (may be rather overblown - the HIDs certainly do have high voltages and swing large currents on startup and shutdown, but a bunch of members are running them with no known issues.) Of course, as a typical light bulb, it'll have to be replaced eventually - HIDs often last the life of the car, though sometimes the ballasts have to be replaced.

Not trying to tell anyone what to do here - just making sure you know the facts, as best I understand them.

 

[AySz88]

As for blinding on oncoming cars, I never get flashed, which suggests this is not a problem.

Frankly, when I get blinded by (low beam) headlights of either sort, flashing the other driver is not one of the things near the top of the priority list. It's not like they can turn them off in those situations. (Some of the time, they're not even in front of me - the light is just reflecting into my eyes from retroreflective road signs.)

 

[artsci]

When I installed my HIDs and checked the aim, I deliberately lowered the beams, then checked them for blinding two ways: with my son approaching in his car on several different roads and by walking away from the car at different 100 yard intervals. No out of the ordinary blinding was evident.

I've had HIDs on all of my cars for at least a decade. I have an Honda S2000, which has factory installed HIDs. In the S2000 I get flashed all the time by approaching cars. Not so with the Volt. So in my book experience, not theory, is the best teacher.

 

[C-Kwik]

So the HIR gives you most of the brightness of the HID, and without using more power than halogen, so it gives you some of the efficiency advantages.

Interesting. Had to read up on it a bit, but I'm surprised we didn't see this type of tech sooner. Then again, it could be an issue of not having the technology at low costs and/or the demand for efficiency wasn't high enough to warrant the research...

Still, I wonder if they might add to this by making it a bandpass filter instead and reflecting the UV spectrum back. Its a smaller range of the EM wave spectrum, but higher energy. Not sure how much, if any, UV light is emitted by a halogen bulb though.

 

[AZ-Volt]

Can you provide more objective information? Like how the beam pattern is projected onto the ground? I believe a topographical map of it with lighting intensity as the elevations is most typical.

I suppose I could, but I really do not wish to further debate the merits of HIDs in the Volt. “my 2 cents” was all about my subjective opinion and nothing more. I have spent hours posting and debating such things on HIDPlanet.com in a previous life. No amount of empirical evidence will make this choice any less subjective to each person. I can tell you that when we picked up my wife’s Volt a month ago I could not wait to do her conversion. After driving my Volt for almost a year with HIDs her stock lights looked so dim and yellow as if they were shorted out. I could not read street signs nor see down the road near as far nor as clear as I can after HIDs…

There is no doubt that there is a geometry change going from OEM halogen capsules to HIDs. I still think the cutoff looks sharper with the HID capsules installed, leading me again, to wonder if they were not intended for HIDs in the first place. The beam width is nowhere near as wide as the S2000 nor is the cutoff quite as defined but Volt projectors converted to HID are far better than many OEM HID projectors that I have personally worked on for retro fit purposes.

HID projector cutoffs are not perfect. As some have pointed out going down a hill or going over dips will raise the cutoff into oncoming traffic. This is the nature of the beast and it happens to all HID projectors OEM or not regardless of leveling systems. Modern leveling systems are not that quick to deal with pitch of a vehicle in motion. Projector cutoffs are still WAY better than HIDs in standard reflector headlight housing which I believe are horrible on the road! Some OEMs still make them that way and certainly a lot of clueless modders do.

So, do HID conversion or do not. I have no reason to try and convince anyone. I posted as I did because I felt the OP was intending to dissuade anyone from doing this. I may be wrong on that but felt another perspective was warranted. I would never go back now that I’ve gotten used to HIDs. This will continue to be the first mod I’d do if I end up with a vehicle without HIDs. Maybe future LED applications will end that need for me, I hope!

Cheers!

Andy

 

[C-Kwik]

I suppose I could, but I really do not wish to further debate the merits of HIDs in the Volt. “my 2 cents” was all about my subjective opinion and nothing more. I have spent hours posting and debating such things on HIDPlanet.com in a previous life. No amount of empirical evidence will make this choice any less subjective to each person. I can tell you that when we picked up my wife’s Volt a month ago I could not wait to do her conversion. After driving my Volt for almost a year with HIDs her stock lights looked so dim and yellow as if they were shorted out. I could not read street signs nor see down the road near as far nor as clear as I can after HIDs…

The problem with subjectivity is that it is purely a matter of perception. And frankly, there is a reason why witness testimony is considered weak evidence in a court of law. So my point here was simply that we can not rely purely on subjective data and frankly we should give little weight to it in light of a more analytical and comprehensive understanding of the subject. Its one thing to opine that you like something better. Its another to say the lighting is better. The latter depends on the metrics. I want to make sure that people understand what the metrics should be.

There is no doubt that there is a geometry change going from OEM halogen capsules to HIDs. I still think the cutoff looks sharper with the HID capsules installed, leading me again, to wonder if they were not intended for HIDs in the first place. The beam width is nowhere near as wide as the S2000 nor is the cutoff quite as defined but Volt projectors converted to HID are far better than many OEM HID projectors that I have personally worked on for retro fit purposes.

Cut-off sharpness in a projector has only to do with the cut-off plate inside the housing. The lights not going to somehow bend around it anymore than it would with the halogens. It might be that the greater light intensity against the dark background provides a bigger contrast. Many could perceive that as a sharper cut-off.

HID projector cutoffs are not perfect. As some have pointed out going down a hill or going over dips will raise the cutoff into oncoming traffic. This is the nature of the beast and it happens to all HID projectors OEM or not regardless of leveling systems. Modern leveling systems are not that quick to deal with pitch of a vehicle in motion. Projector cutoffs are still WAY better than HIDs in standard reflector headlight housing which I believe are horrible on the road! Some OEMs still make them that way and certainly a lot of clueless modders do.

This effect happens with halogen projectors too. HID's have a higher content of blue light and to some extent more light. Glare is caused by a difference in the light and how our eyes are able to handle the wavelengths of light that exist. Our eyes respond differently to red light than it does blue light. There is a reason dark rooms are lit with red bulbs. We do not lose as much ability to see in the dark as we do with other colors.

So, do HID conversion or do not. I have no reason to try and convince anyone. I posted as I did because I felt the OP was intending to dissuade anyone from doing this. I may be wrong on that but felt another perspective was warranted. I would never go back now that I’ve gotten used to HIDs. This will continue to be the first mod I’d do if I end up with a vehicle without HIDs. Maybe future LED applications will end that need for me, I hope!

I didn't get that impression from the OP. Looked like he just wanted to start a discussion on the pros and cons. While I come of as anti-HID, I am not. I love the technology. But any technology, implemented poorly, is not something I will support. Will I tell someone not to do it? Nope. But I will try to better educate someone about a topic and let them decide for themselves. Just a fair warning though. Except for subject matter that is inherently subjective, I generally try to steer most discussions towards more objective analysis when its possible. I apologize if that tends to come off a little brash. But that's one of the reasons I decided to pursue engineering as my second career.

 

[Ladogaboy]

Frankly, when I get blinded by (low beam) headlights of either sort, flashing the other driver is not one of the things near the top of the priority list.

Yeah, sometimes when you flash, all you accomplish is making two blind drivers!

And in terms of the differences, I can attest to the fact that the Volt's headlights certainly are dimmer than HID (what I had in my previous car), and the difference in brightness is noticeable. That being said, it doesn't bother me, personally, because I have pretty good night vision (I can drive at night with no lights and only partial moonlight, though I wouldn't recommend doing so).

 

[AZ-Volt]

Anti-HID or not, clearly you are passionate about this topic. Are you an attorney?

The problem with subjectivity is that it is purely a matter of perception. And frankly, there is a reason why witness testimony is considered weak evidence in a court of law. So my point here was simply that we can not rely purely on subjective data and frankly we should give little weight to it in light of a more analytical and comprehensive understanding of the subject. Its one thing to opine that you like something better. Its another to say the lighting is better. The latter depends on the metrics. I want to make sure that people understand what the metrics should be.

Nonsense. No one needs metrics or some kind of deep “analytical and comprehensive understanding “ to know whether they have improved visibility. That IS a matter of perception and/or opinion and completely valid. Fortunately this is NOT a legal forum. Numerous Volt owners here have expressed dramatically improved night vision with HID conversion and not a single one has said otherwise to my knowledge.

Cut-off sharpness in a projector has only to do with the cut-off plate inside the housing. The lights not going to somehow bend around it anymore than it would with the halogens. It might be that the greater light intensity against the dark background provides a bigger contrast. Many could perceive that as a sharper cut-off.

The intensity of the light has nothing to do with it and I’m not an idiot suggesting light bending around. As you pointed out yourself, the geometry of the two different capsule types DOES make a difference. A sharp cutoff is achieved by the placement of the shield in relation to the focal points created by the combination of the shape and distances of the elements involved, namely the reflector, the lens, the light element itself, and the shield. Thus my comment that the, yes perceived, sharper cutoff may indicate an originally HID purposed design.

This effect happens with halogen projectors too. HID's have a higher content of blue light and to some extent more light. Glare is caused by a difference in the light and how our eyes are able to handle the wavelengths of light that exist. Our eyes respond differently to red light than it does blue light. There is a reason dark rooms are lit with red bulbs. We do not lose as much ability to see in the dark as we do with other colors.

When most people refer to headlight glare they simply mean bright light but thanks for over defining that for us all! To your point, however, HIDs come in many various color Kelvin. While some use higher, 4300K is generally OEM standard for HID and is roughly the same color (temperature) as the sunlight we see on the surface of our planet. I know if I would have just said sunlight you would have pointed out that the color temperature of sunlight varies depending on where you are!

Anyway, the whole point is that our human eyes are best tuned for that color, white, not red or blue. BTW red is used in dark rooms to not expose unprocessed film not to make it easier on the operator.

I didn't get that impression from the OP. Looked like he just wanted to start a discussion on the pros and cons. While I come of as anti-HID, I am not. I love the technology. But any technology, implemented poorly, is not something I will support. Will I tell someone not to do it? Nope. But I will try to better educate someone about a topic and let them decide for themselves. Just a fair warning though. Except for subject matter that is inherently subjective, I generally try to steer most discussions towards more objective analysis when its possible. I apologize if that tends to come off a little brash. But that's one of the reasons I decided to pursue engineering as my second career.

My apologies to KNS if I am wrong (which btw, I did say before mind you) but the tone still appears anti-HID on a re-read. A Volt with decent, proper color temp capsules surely meets your above criteria of properly implemented technology. Again, this is the point I have been trying to make. Volt projectors are some of the best suited for HID conversion as any I have seen. I get what you’re saying about being objective. Certainly this is not as subjective as “what color Volt should I get,” or “how do you like the aftermarket wheels I just bought,” still, night vision is a matter of human perception and therefore by definition IS subjective.

How about you do your own HID conversion and if you don’t like them better than stock I'll admit standing corrected!!!
…assuming you buy good ones that is!

 

[C-Kwik]

Anti-HID or not, clearly you are passionate about this topic. Are you an attorney?

LOL. No. I used to be an automobile claims adjuster though so I've argued with them a lot.

Nonsense. No one needs metrics or some kind of deep “analytical and comprehensive understanding “ to know whether they have improved visibility. That IS a matter of perception and/or opinion and completely valid. Fortunately this is NOT a legal forum. Numerous Volt owners here have expressed dramatically improved night vision with HID conversion and not a single one has said otherwise to my knowledge.

Again, it depends on the metrics. Will brighter light help you see area where the light is actually brighter? For the most part, yes. But our eyes have limitations as to how well we can see distant objects if the foreground is illuminated and vice-versa. Think of the last time you tried to look at the bottom of your engine compartment where it is dark while a light is shining in your eyes from the sun or a light. The same type of thing occurs with night driving. Aiming your beams at a wall, you see a nice hot spot on the wall, but when that hotspot is hitting the ground some 50-100 feet away, its intensity is much lower (times the distance squared in fact) And perhaps it can be balanced out, but then since the housing wasn't designed to do this with an arc capsule, its essentially left to hope that it might. Another aspect rarely thought of that this same effect actually also occurs in our peripheral. That is, while we don't illuminate the sides of the road too much, we still want to see some of it. The brighter the light ahead, the worse our eyes are at seeing what isn't being lit. The design of our headlights takes into consideration a myriad of factors and is a compromise of them. Its certainly not perfect for each task on its own, but it can't be. Our eyes just don't work in such an ideal manner.

The intensity of the light has nothing to do with it and I’m not an idiot suggesting light bending around. As you pointed out yourself, the geometry of the two different capsule types DOES make a difference. A sharp cutoff is achieved by the placement of the shield in relation to the focal points created by the combination of the shape and distances of the elements involved, namely the reflector, the lens, the light element itself, and the shield. Thus my comment that the, yes perceived, sharper cutoff may indicate an originally HID purposed design.

My point was merely that the cut off is the same for either light. Hence, it was not designed for HIDs.

When most people refer to headlight glare they simply mean bright light but thanks for over defining that for us all! To your point, however, HIDs come in many various color Kelvin. While some use higher, 4300K is generally OEM standard for HID and is roughly the same color (temperature) as the sunlight we see on the surface of our planet. I know if I would have just said sunlight you would have pointed out that the color temperature of sunlight varies depending on where you are!

Actually I didn't mean it so simply as to call it just bright light. Glare is relative. That is, if you were to stand out in sunlight and measure the flux of light coming into your eye, and then match some light source directed at your eye to provide the same flux in the darkness, you'll experience glare in the darkness but not in the sunlight despite your eyes detecting the same amount of light. The problem is that you are trying to see things that are providing a much lower intensity of light, but the light is causing your pupils to contract, so you can't get enough light into your eye from the things you are trying to see to resolve them clearly.

Anyway, the whole point is that our human eyes are best tuned for that color, white, not red or blue. BTW red is used in dark rooms to not expose unprocessed film not to make it easier on the operator.

White light is actually made up of the full spectrum of visible light. That's why yellow pass filters look blue to us...they are reflecting the blue, essentially trapping it in the bulbs. Blue-pass filters look yellow. My point here is simply that our eyes to don't adjust themselves equally to different intensities of light at different wavelengths. I reread what I wrote and realize I wasn't too clear. That's my fault. Regardless, yellow is supposed to net the greatest pupil contraction response and blue is the worst. Red light has little impact on our rods. That is, our rods need time before their abilities are maximized in terms of light light vision (If you watch Mythbusters, it has to do with why pirates wore eye patches). Red light doesn't take as much of that away. So given the low light setting, one can still use a dim light, but still see darker areas better than they would with any other color.

My apologies to KNS if I am wrong (which btw, I did say before mind you) but the tone still appears anti-HID on a re-read. A Volt with decent, proper color temp capsules surely meets your above criteria of properly implemented technology. Again, this is the point I have been trying to make. Volt projectors are some of the best suited for HID conversion as any I have seen. I get what you’re saying about being objective. Certainly this is not as subjective as “what color Volt should I get,” or “how do you like the aftermarket wheels I just bought,” still, night vision is a matter of human perception and therefore by definition IS subjective.

I disagree on how I see the OP, but perhaps that's a matter of perception. But again, what you opine as better really depends on the metrics. If brightness is all you are considering, then I would probably agree with you. But better lighting in terms of being able see a good balance of everything you need to see on the road (with some weighting depending on statistical importance), its impossible to say without a detailed and comprehensive analysis. You say its subjective because you are only measuring that which can be measured as such. I'm saying a proper lighting system has a lot more tasks to balance than lighting up the road as bright as possible. If that were the case, you could just take a floodlight, add a cut-off and have awesome lighting.

How about you do your own HID conversion and if you don’t like them better than stock I'll admit standing corrected!!!
…assuming you buy good ones that is!

As stubborn as we both are, I might say admit your wrong and then I'll buy some. haha.

Honestly though, I won't buy it because it wouldn't be worth it to to waste my money on it. If I were to do it, I'd change the housing to accept a true HID system. But even with all the access to machining and fabrication equipment I have, I still wouldn't bother with it. One screw up and I may have to by a whole new headlamp. Plus, my Volt is leased. I tinted it 1st week and received the info about the pre-lease end inspection two weeks afterwards and turns out they may frown on the tint. It'll end up being the only car I have ever owned in which tint is the only mod I have. Which I'm fine with. I'll have plenty of toys to tinker with after I graduate and get a job.