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Old 01-04-2002, 04:26 PM   #13
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Member#: 13896
Join Date: Jan 2002
Default Lighting notes

Howdy, all. Daniel Stern here, with a few comments on some of the observations, questions and notes that have come up in this thread.

"Get a Morette kit": Good advice. Top-quality optics and first-class build quality, all the way. Hard to go wrong with Morette headlamp conversions. Just make sure you purchase them for use on the correct side of the road (US, Canada, Continental Europe: Right Hand Traffic). There are sometimes options as to which optics your Morette kit comes with. For instance, the Y2K and earlier Impreza kit can be had with either H4 or Complex Surface low beam optics. Both are good, but the latter is usually the better choice (NOT always, this depends on your driving conditions!).

"Install HID in your low beams": Usually BAD advice, whether we're talking about factory optics or Morette kits.
There are many unsafe, illegal and noncompliant products on the market, mainly consisting of an HID ballast and bulb for "retrofitting" into a halogen headlamp. Often, these products are advertised using the name of a reputable lighting company ("Real Philips kit! Real Osram kit!") to try to give the potential buyer the illusion of security. While some of the components in these kits are sometimes made by the companies mentioned,
reputable companies like Philips, Osram, Hella, etc. NEVER endorse this kind of "retrofit" usage of their products, for very good reasons:

Halogen headlamps and HID headlamps require very different optics to produce a safe and effective -- not to mention legal -- beam pattern. It is not some great feat of upgrade engineering to put an HID capsule where a halogen bulb belongs, it is just plain dangerous. Some types of halogen headlamp bulbs (9004, 9007, H3) use a transverse (side-to-side) and/or offset (not directly in line with the central axis of the headlamp reflector) filament, the position and orientation of which is physically impossible to match with a "retrofit" HID capsule. Even those halogen headlamps that use axial-filament (9003/H4, 9005, 9006, H1, H7) bulbs are not safely or legitimately "convertible", regardless of what kinds of "clever" base adaptations and claims of "beam correction" the marketers come up with. It's a lot like putting on somebody else's eyeglasses; the optic systems just are not at all compatible. And it's not a question of a "good kit" or a "bad kit"...they are all, by definition, bad. If I had unlimited funds, I'd buy some time on a CCD matrix or linear photogoniometer and put some isoscans from such "retrofits" on my site, but I don't have unlimited funds, so instead I'll talk about
some of the effects of installing "HID retrofit" bulbs into halogen optics:

-Defocused beam; wider but with a relative minimum (looks like a black hole in an isolux diagram!) where the hot spot should be. Effect: Severely reduced seeing distance.

-Vastly increased foreground light. Effect: creates false sense of
"improved" headlamps and illusion of security. The foreground, from 0 to 30m in front of the car, is relatively irrelevant to the driving task at any kind of speed. You need enough light to detect potholes and road obstacles, and enough lateral spread to stay in your lane and on the road, but the amount of light necessary for these tasks is comparatively small.
In addition, a wide and superbright foreground field is extremely damaging to distance vision, because it causes your pupils to close down. Combine this effect with the relative black hole where the hot spot should be, and you've really damaged your nighttime seeing...all the while thinking it's a lot better because of the bright foreground.

-Vastly increased "flare" light in the cutoff region. This is because
the optic system (reflector and lens) count on the very sharp delineation between the bright filament and the dark surrounding space to create the cutoff. The arc has no such sharp delineation; rather, there is a fuzzy ionization glow surrounding the arc. This fuzzy border muddies the cutoff
and contributes to beam defocusing. Effect: Vastly increased direct glare for other road users and backscatter (upward stray light) for the driver in poor weather.

It takes a lot of training and a lot of special equipment to accurately judge a headlamp beam; it's really not something that can be done by shining it up against the wall and guessing. There are MANY aspects that go into making a good (or bad) beam; I can discuss some of them if y'all want, but this is getting long already.

HID headlamps also require careful weatherproofing and electrical
shielding because of the high voltages involved. These unsafe "retrofits" make it physically possible to insert an HID bulb where a halogen bulb belongs, but this practice is illegal and dangerous, regardless of claims by these marketers that their systems are "beam pattern corrected" or the fraudulent use of established brand names to try to trick you into thinking the product is legitimate. In order to work correctly and safely,
HID headlamps must be designed from the start as HID headlamps.

Now, the top-name headlamp optic manufacturers (Hella, Bosch, Valeo) are beginning to market modular HID Xenon optic units, some of which have the same mechanical fitment as those companies' halogen modular optics. Those could safely and effectively be used as retrofits for halogen lamps, because they are meant for HIDs. Morette kits are not available with HID because European regulations require automatic beam levelling (to compensate for cargo loading of the car) and lens-cleaning equipment on HID headlamps to prevent the extreme dazzling glare that otherwise occurs. This equipment isn't required in North America on HID headlamps, but that means you have to be MORE careful not to cause glare -- not that you can ignore the issue. Glare isn't safe.

The Cibie and Hella optics used in Morette kits are top stuff. Put good bulbs in them and feed them properly with good wiring and relays and there's utterly no need to spend the $$$ and downgrade your safety with an improper "retrofit" of HID. Spend the money on other go-fast goodies or ten nice dinners.

"Never use overwattage bulbs": Certainly not with stock wiring, and certainly not unless you have headlamps that have half-decent glare control (ones that use 9003/HB2/H4 bulbs at the MINIMUM, preferably European-spec units...NEVER with 9007 or other DOT junk which produces tremendous glare even with stock wattage).

"PIAA" : Very heavily-hyped, very high-priced junk.

"Cibie, Bosch, Hella, Morette": Now you're talking.

"Competition Limited bulbs weren't as well made, didn't last, and didn't make much difference": This is why you should avoid 3rd-world garbage, no matter who is selling it or what claims are made!

"Xtrawhite, Hyperwhite, Ice white, Superwhite, Ionwhite": Absolutely no seeing benefit, and science has yet to give us the filtration coating that adds light...they all subtract light.

"Where to get harnesses": IPF, Painless Wiring and a couple others sell good-quality prefab units; Competition Limited sells lower-quality items (not necessarily "cheaper", though!). I and other suppliers sell all the parts you need to make your own.

"97 vs 99 headlamps": Yep, this was an area of cost reduction.

It's *HARD* to get European-spec Subaru headlamps in North America. I've been working on sourcing some of them...some folks have written-in saying they want the better E-code performance, but they don't want the Morette or Subaru Rallye car "multi-eyes" appearance. The solution would be stock European headlamps. I know I'd put a set on my Y2K OBW.

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