Adaptive Headlights

Adaptive headlights pivot the beam slightly for turns and curves. Don't have them myself, but I'd think they'd be useful. HID low beams are a real plus.

BMW marketed dual Xenon for awhile in which the HID bulb had a mask that would rotate around the filament when high beam was selected and allow an HID high beam (the mask effectively removed the sharp cutoff typical in an HID low beam). These can be found in the aftermarket. Not sure what wiring issues would be involved.

You can also install higher output Halogen bulbs (if you don't have or don't want HID), but if the wattage is too great, you'll risk deforming the housings and lenses from the extra heat and they also might stress the electrical wiring.

Beware of the blue tint bulbs. Most tend to put out less light than the somewhat yellowish halogen units.

R / John

The factory OE Xenon adaptive headlights is an excellent option for those needing better night vision and at what, about $800, is a BARGAIN. I pity the fool who passes on this bargain and then later decide he wants it.

Well, in all fairness it is possible to install halogen driving lights that will light up the road better, cost at least half as much, won't give you nast backdazzzle in inclement weather and aren't as offensive to oncoming drivers.

Yeah those blue lights sure are purdy and all, but...

I'm not quite sure how you'd do this? There's no problem with getting a main beam to be as bright as you want, but providing a decent dipped one without dazzle is the difficult one. And in the UK at least you can't use 'driving lamps' to do this.

Discharge lamps of the type used on cars can be any colour temperature you want. However, the eye is more sensitive towards the blue end of the spectrum than it is to the red, so 'red' halogen lamps don't really make sense. But of course HID lamps *are* brighter so more likely to offend others.

You can have auxilliary driving lights right? I mean you aren't going to need them in downtown London at night but in the country you can turn them on and light up the next three counties.

Yeah and everybody wants that damn blue.

"brighter" than what? I've got some Marchals halogens here than will melt the bumper of the car in front of you if you get too close, to say nothing of the Cibie CSR's.

Also, blue reflects the short wavelenghts so in cloudy/foggy conditions (how RARE in merry 'old) they're the last thing you want. Effectove "fog" lamps are yellow, not blue.

I'm just not sold on HID lamps. Too expensive, too useless around here - which is almost as foggy as ukkers.

Are you sure about that Dave? I thought I had read somewhere that the eye is *less* responsive to blue light than longer wavelengths, especially yellow. OTOH, I also know the eye is also not very sensitive to red light considering that is the color used in "night rigging" ships to maintain better night vision of the crew. Perhaps the eye's sensitivity drops off at both ends of the spectrum?

Yes, so even if the eye is marginally less sensitive, the increase in light volume provides both the driver and the oncoming traffic more signal to the brain.

No, human eyes are more sensitive to green that to either red or blue. There are lots and lots of references, but really this newsgroup is about cars not eyes. Jim

They can only be used with main beam - and on most cars main beam is already fine. It's dip that is the difficult one, and in a crowded country like the UK you spend most of your time using that even on the open road due to oncoming traffic.

Currently, the most efficient HID lamps do look blue compared to halogen. But are in fact closer to daylight.

You can have HID lamps of near any power - same as halogens. Film lighting have been using them for years with sizes in the killowatts.

You'll find as many opinions on the best colour for fogs as you will fogs themselves - but most are now just plain old halogen. It's the beam pattern that gives the best results.

Then you really need custom foglamps. Which could use an HID lamp.

Right... and we don't use our eyes when driving cars, do we? And the disussion is about the color of the light cast by the headlights that are mounted on our cars. How much more on topic could this be?

If the OP wanted to know if the Adaptive headlights were worthwhile enough to order as an option, then yes, it will much cheaper, $800 now than later. You will also get self leveling, and high pressure washers.

Once the color temp gets above 5K deg K It tends to be blue. Old human eyes don't see blue very well. IMO, anything > 5K is really a waste of money. I have had several HID sets at 4300 and it was a very pure white light. If I remember correctly, daylight is 4700K?

It's most sensitive to green of the three primaries. But more sensitive at the blue than red end - at either side of the roughly centre green. We're used to tungsten filament lamps being towards the red end of daylight - which is probably why many HID types look blue in comparison. If all lights were HID of the same colour temperature they'd soon look the norm.

Surely it's fair enough to discuss car lighting, and how that interfaces with the eye/brain combination?

And I'm certainly not in favour of 'any colour' lights were it's simply a fashion. But feel high efficiency discharge types will be the way forward

- as well as LED for low powered applications. Increasing the efficiency of car lighting reduces cable weight and energy consumption, as well as hopefully safety, and anything which does this can't be all bad.

The eye is most sensitive to green. This is why most fluorescent tubes spike in the green portion of the specturm - they look brighter. This is why they show up as green on regular film. They ARE more green, but your eyes normalizes the light and it looks "normal" when you're used to them.

The longer the wavelength of light the less is scatters in fog. This is why fog lamps are yellow and why backscatter with blue halogens in inclement conditions is becoming increasingly of concern to NHTSA.

Expect to see more white HID lamps. Blue is like, so passe now :-)

Note also those blue incandescent bulbs sold as fake HID's are flat out illegal, the only legal front facing bulbs are white and yellow.

Check your local lighting regulations. They are, if nothing else, worth a laugh.

Tropical daylight at noon on the equator is 5000K. Northern climates, at noon are 7500K. The more north you go the bluer it is.

This is usenet. Everything is fair.

That's pretty naive in my opinion. Nothing could be easier than incandescents. You apply voltage to two pins and they make light. They're cheap.

HIDs ARE great, but, they have a lot of problems with automotive applications: they don't come on instanly and a lot has to be done to get around this. They require weird voltages and an extra large striking voltage. They're expensive and complicated. They are however more efficient so you get the same light from less voltage and that's important. They're not THAT much brighter, they just look brighter because of the color of the light. When a "lamp driver module" is one small cheap chip (a ways off yet) and all the costs have come down they're probably be near-ubiquotous, but that's at least a decade off IMO.

LED"s are good but they're a point source that doesn't radiate like a coaxial incandescent filamwnt so they have their own set of problems. WHat would be neat is a "filamnt" in a bulb, the same shape as a regular incandescent filament but works like an LED not a thing that burns white hot when voltage is applied.

So you want brighter low-beams? Uh... it's a bit of a contradiction to want to light up the road better but nor blind the guy in front or the guy coming the other way.

Daylight is blue. The sky is blue not yellow.

Sure, and GE make a 10 kilowatt carbon arc lamp for lighthouses but we're talking car bulbs here.

It's not an opinion that you can see bettwe in fog with yellow light. Or why shooting glasses for foggy says have yellow lenses.

Other than the fact none exists, sounds swell.

Really?

Well just about everything on a car has moved on with improving technology. Or perhaps you want to go back to points ignition? That's cheap too. As is a nice single downdraught carb.

Err, how often does it get dark suddenly? I've never found the time they take to get to full output a problem.

They *sell* for much more. But then so does everything when it's new.

Actually, less current.

They produce approximately three times the light for the same current - not difficult since incandescent lamps are incredibly inefficient.

For things like tail lights etc you don't need omni directional radiation

- indeed this just means you have to add some form of reflector.

For many applications around the car, filament or point source lamps are anything but ideal. Interior lighting for example would be better with large soft sources. As would most other lights apart from headlamps. We're simply used to filament lamps - that's all.

No it's not. By definition.

So the sun is blue? That's what provides daylight - not the sky.

Really. That's my opinion. It's not a fact and reasonable people disagree all the time. I'm listening.

No. We're talking about lights here.

Well, YOU haven't had a problem but the fact remains, with incandescents when you turn on the switch you get full brightness immediately. There's a non-zero chance this will be a problem somewhere sometime.

I know why, I'm just pointing out it falls in the "con" not "pro" column.

True. Less energy what what I meat to say and module some teenager pranging in my ear I actually might have.

Understood, but incandcents, using more energy yield very close to the same light, and advanced ones lke CSR's put out more light than HIDs.

No and no. You need to check lighting regulations and yo're guessing (wrongly) about the reflector.

Well, I've tried LED's inside. Worthless. You go try it ane lemme know what you think. Luxeons are nice ones to play with.