LED bulbs not so bad

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"In real life", pre-"electrochromatic mirrors" cost hundreds of dollars. Not cuz today's mirrors are expensive for the EM technology, but cuz they mold the damn things into the body instead of jes making it a bolt-on attachment. Heck, EM welding helmets can be had fer $39! So, why do non-EM sunglasses cost $300!? Don't get me started......
nb
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notbob wrote:

Because people buy them. Subaru has another gadget. It has compass embedded in rear view mirror red letters E, N, W, S, etc. after few years the letters don't light up needing to replace the whole mirror which is expensive. CVT has two solenoids molded in one with one connector. If one goes won't shift. Have to replace the whole assembly costing like 1500.00. Usually goes right after warranty runs out. Look at those people lining up at the store trying to get their hands on new iPhones. It is all our fault......
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The height of the lamp isn't the issue. As you noted, it's the aim point and the coverage area. Misaimed headlights are frequently too high and stray into the oncoming lane.

They aren't. The DOT regulates how bright a standard headight can be.
http://www.ecfr.gov/cgi-bin/text-idx?node=se49.6.571_1108
Table XVIII and XIX - note the Maximum Photometric Intensity column. People think High Beams means brighter - it doesn't. It means the aim point is higher. People also think some lamps are brighter because the color temp is different - more blue than incandescent or halogens. That's also regulated, but not as tightly.
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On 11/28/2015 9:24 AM, Arthur Conan Doyle wrote:

There are two different issues at play. One is left to right aiming: the driver's side (inner) headlamp is supposed to point "right" instead of straight ahead. This keeps your lights out of the "other lane".
But, height/elevation also plays a role. If you're lights are higher up off the roadway, they will cross a given point of elevation that lower mounted lights won't. E.g., an 18-wheeler's lights are more likely to be up *above* my eyes, pointed downward, than a MiniCooper's.
In each case where "oncoming" drivers "flashed us", they were parked (at a light) directly across the intersection from us. I.e., close enough that our light cone hadn't fallen to a point BELOW the driver's eye level.
Living in a world of pickup trucks, we had noticed this early on: "Why are everyone's headlights so bright?" But, you'd only notice when the offending vehicle was very close -- not "down the road a bit and headed in your direction". The "solution" is to get your vehicle *up* and out of the downward aimed lights sooner.

Exactly. "High" and "low" aren't synonyms for "bright" and "dim".

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On 11/28/2015 10:24 AM, Don Y wrote:

Properly aimed, they should not be blinding others no matter how bright.
One possibility is some drivers just see they are brighter and assume you have the high beams on even if they are not blinded.
Possible aim is bad from the factory. Unlikely, but stuff happens.
The factory specs are less than the best. I sometimes do notice the Jeep SUV type is a bad aim for oncoming cars. I see a couple of them and they are brighter in my eyes than any other car.
Another possibility is you have 6 bags of concrete in the trunk and the lights are looking up. Many cars have self leveling lights though.
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On 11/28/2015 9:41 AM, Ed Pawlowski wrote:

See my other posts, here. The issue is elevation of the headlamp. The first time it happened, we (new to the car) went to "lower" the beam -- and ended up flashing the highs, instead. So, the other vehicle now *knows* we didn't have the highs on.
Had he been in a pickup truck or other "high riding" vehicle, he would probably not have noticed. Or, had his vehicle been in relative motion to ours so he wasn't in the "bad spot" for the duration of the traffic light.
It's also possible that seeing the "wider" light source (3 lamps each side instead of just one filament) led him to think it was two bulbs, side by side.
And, they're "whiter" than normal incandescents.

There's a real spare in the trunk (instead of a bottle of sealant and a pump) but I doubt that makes much of a load difference (~100#?)
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Don Y wrote in alt.home.repair:

There is an angle higher cars ned to use to not blind others. It is the law. Higher car does not matter.
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On 11/28/2015 11:27 AM, cshenk wrote:

Think about what you've said. Now, take out a piece of paper and a ruler and draw your "solution". Better yet, cite the actual ordinance so you know you're drawing the right elevations, spacings, etc.
Tell me how car height "does not matter" -- to the geometry involved?
In most states, car headlights have to be between ~24 and ~54 inches "above grade". The ROOF of *my* car (not SWMBO's vehicle which I've been talking about) is LOWER than that! So, my *eyes* will be even lower, still!
Please tell me what sort of "angle" those "higher cars" could adopt to keep their lights OUT of my eyes? Perhaps pointed STRAIGHT DOWN??
Headlamps are not point sources. Nor are they highly columnated (i.e., the light cones *disperse* else they'd be pretty USELESS at illuminating the roadway ahead -- you'd only be able to see two *points* on the road at some fixed distance ahead!).
Roads are not level. The person some distance in front of you may be at a higher or lower elevation; and, the roadway on which you (or he) are situated may be inclined (pointing lights upward or downward).
The distances between vehicles (light source and incident surface) can vary.
I'm eager to hear of the revolutionary geometrical principles you've uncovered that ENSURE *legally* conforming lights can't shine in another driver/passenger's eyes! :>
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Don Y wrote in alt.home.repair:

Play with someone else.
If folks are flashing lights at you, something is wrong at your end.
On a level road, there is a point where the central beam is to hit the road. I don't know the exact feet it's supposed to be. If you set it 20 feet further out (aka higher beam) you blind other drivers unacceptably. This point of hitting the road x feet ahead, does not change based on vehicle height. Only the angle of the lights changes based on height of vehicle.
It's really basic middle school geometry level stuff.
Carol
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On 11/28/2015 5:09 PM, cshenk wrote:

No. You refuse to acknowledge that the world doesn't consist solely of flat roadways, divided highways, rational drivers, etc.

When I leave my subdivision, I am pointed uphill. At the crest of the hill is a light. Traffic coming *towards* me is ABOVE me. Simple geometry (ray tracing) suggests the centerline of my headlights will *climb* with respect to the other car's elevation as long as the uphill slope of my roadway exceeds the ~2 inches per 25 ft that my headlights are intended to AIM DOWNWARD.
If my headlights are already "high up", then they've got a head start in their journey to the opposing driver's eyes.
Opposing driver is in his left turn lane. I am in my left turn lane. MY HEADLIGHTS WILL SHINE DIRECTLY ON THE FRONT OF HIS VEHICLE. Neither of us are on "the wrong side of the road". Yet, my body is "farther left" than *his* body! I.e., my RIGHT headlight can hit him square on just as easily as my left.
We're both *stopped* in these positions -- and will remain so for the better part of a minute. Unlike if we were *traveling* in opposing directions. So, we each have plenty of time to notice the other's lights in our eyes.
As mine are closer to points of light (than a traditional, large "sealed beam" light that spreads the light out *before* it leaves the reflector), mine will appear brighter. As mine are three individual point sources side by side, he can mistakenly think of them as "multiple bulbs" -- instead of the single "lighting element" that they represent.
Draw a little picture. "It's really basic middle school geometry level stuff."
As I said, if we had a "problem", folks would CONSTANTLY be flashing their brights at us. Coming face to face with a police officer should result in an instant citation, right?
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Don Y wrote in alt.home.repair:

Go play tootsies with someone else.
--


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On 11/28/2015 6:33 PM, cshenk wrote:

All you have to do is IGNORE my posts and you won't see them! Gee, isn't that wunnerful?
I think I'll go toalk to the sheriff tomorrow. Be nice to KNOW I'm right. And, see how folks can so blindly exhibit faulty logic.
(Occam's Razor. Easier to believe factory built car wrong? But, only *some* folks notice it and alert us to that? Or, that those same folks get light caught in their eyes and have only one instinctive reaction: flash their high beams? I bet you believe 9/11 was a massive CIA conspiracy, too! :> )
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cshenk wrote:

You think premolded LED array assembly which is part of car body can be adjusted like old head lights? I bet LED arrays passed DOT testing and legally approved.

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<stuff snipped>

Implementation is for lower life forms. <g>
I propose that everyone traveling west to east wear polarized glasses and cars traveling from east to west have lights that are polarized in a different plane. (sarcasm alert!)
--
Bobby G.



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Robert Green wrote:

How about blinding all the light like war time.... No more shining into your eyes.
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On 11/28/2015 9:09 PM, Tony Hwang wrote:

Outfit each car with a white cane!
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On 11/28/2015 2:27 PM, Don Y wrote:

I just read http://www.danielsternlighting.com/tech/aim/aim.html Nomatter the height of the light there is a small trgt range to hit at the 25' distance. Another factor is horizontal aim, but some desighns have little control over it.
Although you state the light is not comumner, the desighn does limit the amount of light beamed to the left of the car so it does not blind the oncoming cars.
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Ed Pawlowski wrote:

Left of the car? Would that be right of the car? I am confused.
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On 11/28/2015 9:12 PM, Tony Hwang wrote:

And that target area is RELATIVE TO THE HEIGHT OF THE HEADLAMP, not the ground! I.e., a headlamp located 30 inches above grade will "hit the roadway" farther away (from the headlamp) than a headlamp located 25 inches off the roadway. So, "car height matters".
And, the resulting downward angle is almost immeasurable: 2 inches over 25 feet. A roadway with a 1:150 slope would be comparable (i.e., practically indistinguishable from "flat"). As such, if your vehicle is on even the slightest of upward roadway slopes, the headlamp "beam" will CLIMB as it leaves your vehicle. If another vehicle is directly in front of you (as in two opposing vehicles each in their respective COINCIDENT left turn lanes) then your lamps will shine directly into the other driver's eyes. And there's nothing you nor the factory nor the dealer can do about it. "Simple geometry" :>

And some designs have no independent control over the "high" element.
Conventional headlight designs have one bulb with two filaments and/or two bulbs. I.e., two physical light sources which can potentially be adjusted independently of each other.
In our case, there are *5* light sources in each headlamp; three for the "low" beam and 2 for the "high" beam. Without even looking at the car, I can safely state that the two "highs" are not adjustable independently of each other. Nor are the three "lows". Doing so would add far too much labor to what should be a trivial manufacturing task ("insert headlight assembly") -- having to make *10* adjustments just to ensure all 10 elements (2x(3+2)) are pointed in their correct directions.

The role of the *optics* is to constrain the beam's dispersal pattern. Otherwise, light exits the "lamp" in an uncontrolled manner. A laser is the typical example of highly coherent light -- it *all* goes in one tight, narrow beam. There's no "splashover" in unintended directions.
Headlamps that resolve to *points* at long distances would be completely impractical. They wouldn't show you more than "two particular points" on the roadway from any given car position and orientation. Imagine fastening two laser pointers to the front of your vehicle... *But*, they wouldn't venture astray and end up in another driver's eyes! :>
So, you want to allow the headlamps to cast a wide beam -- without crossing a line into "oncoming traffic". (assuming, of course, that your car isn't POINTED into oncoming traffic due to the geometry of the roadway, etc.)
The optics on the five "bulbs" in each of our headlamps differ based on the intent of the light they emit. The 3 "low beam" emitters (towards the outside of the vehicle) are almost (hemi)spherical in appearance. They look like 1.5" glass BALLS! The actual emitters (LEDs) are located directly behind them -- pointing forward THROUGH these globular lenses.
By contrast, the 2 "high beam" emitters are located *below* the "bulbs" (loosely speaking... "the points at which the light appears to exit the headlamp"). They face SKYWARD! Instead of a globular lens, they shine into a curved mirror, of sorts, so the light takes a right-angle turn as it leaves the headlamp. No doubt, this allows the light greater leeway in its path forward.

Best think in terms of inside/outside -- you want to orient the light field from the headlamp(s) towards the roadside instead of towards oncoming traffic.
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On 11/29/2015 12:01 AM, Don Y wrote:

Yes, the same design that limits the light in the other guy's eyes on a two lane is the cause of the potential blinding when head on. Can't help it.

I imagine the entire assembly can be aimed, but there is no need to do them independently. The factory design should be fixed so they all aim in the proper direction and no need to move just one. Most likely they are in a molded housing.
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