This is an article about a particular brand of headlight bulbs — Eiko Clear Vision Supreme with SoLux™ Technology — but before we get there, some backstory: by Daniel Stern. Special to acarplace.com.
This is an article about a particular brand of headlight bulbs — Eiko Clear Vision Supreme with SoLux™ Technology — but before we get there, some backstory:
Not too long ago, the word most used, abused, and misused in the world of automotive lighting was “Xenon.” Every marketeer slapped “Xenon” on the package in hopes it would distract you out of questioning the high price (and usually short life) of the bulbs. Pesky facts (such as all halogen bulbs containing some xenon gas in their fill mix) didn't matter; what was important was capitalizing on a usually-undeserved association with the high-intensity discharge—HID, popularly called “Xenon”—headlamps that were new at the time.
But HID headlamps aren't new any more; LED headlamps are the latest new thing, and there's no easy way to hook a marketing line effectively from halogen bulbs to LED headlamps. So what's the new word of the day? Why, it's “Technology!” Today's marketeers feel as long as they can work the magic T-word into the conversation, you'll come to believe they've got something new, something different, something better, something certainly worth spending extra money. And once you've spent the extra money, the Slick-50 effect (“Of course my engine runs better and my car gets better mileage; I just spent $50 on a bottle of Slick-50!”) pretty much guarantees you'll crow to all your friends about how much better your headlights work with the new bulbs. It's not your fault, you're not being stupid, you're just being human. And the marketeers are being marketeers, exploiting the idiosyncrasies of how the human mind works.
So everything's billed as a “technology”, whether it merits that description or not. Mostly not; I can say I'm going to “deploy lipid-disintegration surfactant and hemmed-microfiber absorptive technology to take my fenestral visual clarity to the next level,” which sounds all cutting-edge and certainly worth money, but all it means in the real world is that I'm going to clean my windows with soapy water and a rag. Much less sexy, but hey, if you can't dazzle 'em with brilliance, baffle 'em with BS and listen to the cash register ring.
And so it is with most headlight bulbs marketed as an upgrade, especially that “can't dazzle 'em with brilliance” part. The Eiko people, for example, have made a great business for themselves selling Chinese-made household, automotive, and technical light bulbs under an increasing variety of product names. One of those names is “Solux.” That's the name Eiko uses for their bulbs with blue glass to tint the light towards a bluer (colder) white color. It doesn't make the light “whiter” or “brighter”, it just tints it slightly towards blue.
That's all it is: blue glass bulbs, packaged up as “Clear Vision Supreme Headlights with SoLux™ Technology”. Is a glass color selection really a “technology”? No, it's just a glass color selection. And it can be a legitimate one in certain applications—art galleries and retail stores, for example, where a particular artwork or piece of merchandise looks best under light of a particular shade.
But not for the task of seeing while driving at night. Any bulb that has a blue or purple tint to the glass and claims to produce “brighter” and “whiter” light actually does neither, and that applies no matter how much the marketeers might talk about “technology” (or “closer to natural daylight” or “high color temperature” or “high kelvin rating” or any of the other handwaving language they use together with Photoshopped images purporting to show a wholly unrealistic “improvement” from using their bulbs). The laws of physics don't allow such claims to be true. Fact is, when you put a colored filter in the system, you're blocking some light that would reach the road if it were travelling through clear glass.
That's how filters work: they filter. There is no such thing as a filter that adds light into the beam; a filter can only take light away from the beam. The “whiter” light appearance is a result of this filtration. Some people find it more appealing, and many people experience the illusion of “improved” lighting from it, but that's all it is—an illusion.
The human visual system is a lousy judge of its own performance; it's very easy to create the feeling of being able to see much better or worse than we actually can. In fact, the altered (tinted) light from “whiter light” bulbs does not help you see better under any conditions, and particularly in rain, fog, or snow, it's much worse. The illusion of “better” lighting is dangerous when in fact your headlamps' objective safety performance is degraded. And as a triple whammy, adding insult to injury, the blue-glass “extra white” bulbs have a short lifespan because the filaments must be overdriven to get bare minimum legal levels of light through the tinted glass.
So no, objectively what you need for better and safer seeing at night isn't tinted “whiter” light, it's more light, properly focused and going where it's supposed to go.
And that brings us to the next point: basic bulb quality. Bulb quality matters! The filaments must be exactly, precisely where they're supposed to be, and they must be exactly the right size and shape. Any tiny distortion or misplacement is greatly magnified by the headlamp optics (which are designed to look at a properly-manufactured filament), and the result of using a bulb manufactured with lax quality control is a substantial reduction in beam focus and safety performance from the headlamps.
It's a bothersome fact of life in today's global economy that we can no longer buy a lot of parts and tools made in countries we'd like to buy them from; often we are forced by lack of option to buy products made in countries that have a reputation for poor quality—and toxic toothpaste, and poisonous toys for kids, and contaminated food, and toasters that burst into flame, but I digress. Fortunately, that is not (yet?) the case in headlight bulbs.
Unfortunately, you can't avoid bad bulbs by simply sticking to reputable manufacturers; all the makers, even the major ones, have found there's a lot of cash to be made pushing blue-glass “extra white” bulbs and treating your headlights as a fashion accessory rather than as the life-safety equipment they are. Sylvania Silver Star/Ultra, and ZXE, Philips Crystal Vision and BlueVision, PIAA, Hoen, Wagner TruView, GE Night Hawk Sport...it doesn't make any difference whose name is on the package or how much verbiage there is about the “technology” involved—all of these are the same “extra white” scam. If you take the time to read the fine print in the claims made for the various “whiter light” bulbs, you'll find you're not quite being lied to, but you're also not quite being told the truth, either; at least one manufacturer bases its claims of such-and-such percent more light from their “ultra' bulbs on a comparison not with a new standard bulb, but with a used, aged standard bulb or one that is not being fed full voltage.
So it pays (not just in headlight performance but in dollars as well) to be very picky about the bulbs you buy. The top performers in the American market are Philips Xtreme Vision (not CrystalVision, not NightGuide) and GE Night Hawk Platinum (not Night Hawk Sport). These can be tough to find locally, but they're easy to find on amazon.com
“But wait,” you say, “What about that blue ring I see at the tip of the Night Hawk Platinum or Xtreme Vision bulb? I thought you said no blue glass!” That's a very reasonable question and the answer is not intuitive.
Each headlight bulb type has a Federally- or internationally-regulated output specification, to make sure that headlamps designed for use with any particular bulb type (9004, 9007, H7, whatever) will give safe, legal performance no matter what brand of (legal) bulb is installed. The specifications for output are given as a nominal value and a tolerance range, typically ±15% (though the actual tolerance varies by bulb type). That's a very wide range. For example, a 9006 bulb has a specification of 1000 lumens ±15%, which means a 9006 bulb can produce anything from 851 to 1149 lumens and be legal, a total range of 30%.
The idea behind the tolerance range is to allow for the variance that comes with mass production, but bulb makers have enough control over their manufacturing processes to be able to consistently make bulbs that are near the high end, near the low end, or right in the middle of the specification. It's not that they set out to make a bulb that produces just the minimum legal amount of light, it's that there may be other priorities at work, such as having an extra-long bulb life, or having “extra white” light color by means of tinted glass—both of which mean trading off bulb performance to achieve that other goal.
Now back to that blue ring: when headlight bulbs are tested for compliance with the Federal or international standard, they're placed in a device called an integrating sphere which measures all the light coming from the bulb in all directions. Filament bulbs radiate light in all directions, so this is the right way to measure their output. That blue ring is up at the forward end of the bulb, and when the bulb is in a headlamp there's no useful light that travels through that forward portion of the glass; it's too far forward for light to travel that direction and still hit the reflector. The blue ring is there on extra high performance bulbs to reduce the total amount of light emitted by the bulb to just under the legal maximum, while much more light than from a regular bulb travels through the clear, uncolored part of the glass to the lamp reflector and from there to the lens and out on to the road. It's a neat trick; not only does it allow top performance from the headlamps but it also gives the marketeers a styling element to talk up (a consequence-free one; the blue ring creates a blue glint at certain angles when you view the headlamps, but doesn't tint/filter the light within the beam). It also proves the point about blue glass blocking light. If that blue glass isn't just a ring at the tip of the bulb, if it's the whole bulb capsule, no matter how light the blue tint might be, it's stealing light from you.
But that still leaves us with the question of what to do about the color of light from our headlamps. First we have to accept that halogen headlights will never look like HIDs or LEDs. They're different technologies (hey, look! The word can be used properly!); they generate light in fundamentally different ways, and trying to make one look like the other is futile.
That doesn't mean you have to put up with brownish, dingy-looking light. Tinting the headlight bulbs is the wrong way to deal with it because it just masks the symptom, so what's the right way? Fix the problem! It's a result of starved bulbs, endemic to many vehicles because of underspecified headlight wiring. Thin headlight wires create voltage drop in the circuit, which starves the bulbs. Bulb output doesn't drop in a linear, 1:1 relationship with voltage drop. The relationship is exponential to the power 3.4, so a seemingly minor 8% voltage drop costs you a full 25% of the light you should be getting from your headlights, and because filament bulb color is highly dependent on the voltage they receive (think about the dimmer in your dining room)...you get brown headlights! There are two ways to address the issue. The most proper way to do it is to install headlight relays and good, large-gauge wiring as described here and at allpar.com.
Another way is to install lower-wattage bulbs. Stay with me here; this isn't as crazy as it might seem. The lower the bulb wattage, the less demand it exerts on the headlamp circuit, and so the less effect from the inadequacy of the headlamp circuit. A circuit that may exhibit 8% voltage drop with ordinary bulbs might show only 4% drop with low-wattage bulbs, cutting the light loss from 25% down to a much less alarming 13%. Still not ideal, but much less awful. This kind of bulb is available from Philips (EcoVision)
It's a neat trick, and it works. Real-world headlight performance on a vehicle with a marginal headlamp circuit is often better with the lower-wattage bulbs than with normal or high-performance bulbs.
Finally, your headlamps must be properly made (all the aftermarket ”crash part” items are junk), in good condition (if the lenses are clouded up, polishing will postpone the need to replace them, but that's all it will do), and aimed correctly.
With headlamps in good condition, fed properly by a good wiring system, equipped with bulbs selected based on science and facts rather than on marketeering baloney, and aimed correctly, your nighttime driving will be a great deal easier and safer no matter how good or bad the headlamp design is on your particular car.
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