OEM Xenon Projector install.

[mrb]

Sorry, long post time...
OK, so after collecting parts for what seems an age, I've just had my ECE OEM bixenon installed. They are AL 3" Bixenon.
Few pretty poor pics below:

I'd very much appreciate any help/answers to some/any of the points I have below.

My 4 questions relate to the aim and output of the projectors.
Initial aim was set (on purpose) too low and later moved up. Following manufacturer (and DS lighting guide) ie ECE 1% so @5m distance the lower right portion of the beam is 5cm below projector centre point and at 10m, 10cm below cp.

Adjustments made were on the conservative side and after a quick test run I must say I'm a pretty underwhelmed.
As this is my first experience of projectors I'm not yet used to their beam characteristics.

Output width-wise at least is vastly superior to my reflector setup.
In terms of throw the transistion from illuminated to non-illuminated areas seem very, very abrupt and very close to the car.
Perspective issues aside, it looks like only about a few car lengths of illumination before the cut-off begins, I would not be at ease using them out of street-lit areas at any speed as they are.

Q1: Are these just the traits of all projectors in general at play here or do I need to double/triple check the aim?
When I moved the aim slightly up to the point where illumination seemed a bit better I got flashed by a big truck, I don't know if this was just a coincidence as no more flashes from there on.
Note: The "did I get flashed or not" is not the method I'm going to use/employ to check aim, it's not the correct way to do things.

Q2: Throw-wise when correctly aimed what would be the ball-park figure of distance before cut-off for ECE projectors?

Q3: Poor pics but is the amount of colour artifacts around cut-off normal for such a unit? They are yellow at close range and shift to other colours at range. These projectors are stock in terms of the optical path and no mods to the shield or lens placement have (or will) been performed.

Chinese Burner:

Osram Burner:

Chinese burner had big issues and not in use, am using new Philips CM d2s.


Q4: Assuming I recheck the aim again and am satisfied with the throw, my other concern is the self levelling for my particular car model does not occur on a continuous basis. The control unit only polls/samples the 2 hall-effect level sensors approx every 30 secs or so.
This means that ridges and road imperfections that upset the car will not be reacted against fast enough. I have witnessed many other xenon projector shod cars that seem to have this nodding phenomenom too so is it really a non-issue as it isn't a constant mis-aim?

I've yet to get any night time shot of the xenon but did take some long exposure shots of my standard Philips H7 reflector setup.
Day Control Shot:

It seems to me that projector adjustment is a fine line from being sufficient to get any depth versus not causing excess glare.

If I cannot get at least a similar (hopefully better otherwise what's the point?) throw result from the projectors whilst still being safe for other users then they'll be coming out and the reflectors will go back in and lessons will be learnt!

TIA

********Update: Bixenon pics added.************
Had to reduce exposure time to 3 secs for the bixenon pics and change to daylight white balance. Thought my camera had gone bad, with tungsten WB set a pic of xenons came out almost green. Should have shot the halogens with daylight WB really.:oops:

The 2 shots below are same exposure. About 1½ hrs before sunrise for 1st pic, about 2hrs before sun up for second.

With bixenon active it is more than enough to see pretty far into the fields at either side.
Can't really say that I at least would need any more light than this, though still getting used to that abrupt projector cut-off.

 

[-Virgil-]

The sharper the cutoff, the more crucial becomes proper aim. Find a garage with a beamsetter; no matter how level you think the ground is that the car's sitting on (plus the distance to the wall), it's almost certainly not.

The color artifacts don't look abnormal in your pics.

Reach length to the cutoff on your side of the road can be calculated with trigonometry for any aim angle. The height from ground to the center of the projector is your vertical, the distance on the road surface to the cutoff is your horizontal (you're trying to find this), and from the center of the projector to the cutoff on the road surface is your hypotenuse. The angle between vertical and horizontal is 90 degrees, and the angle between hypotenuse and vertical is your aim angle. It will be slightly less than 90 degrees. For 1% aim, that's 0.573 degrees below horizontal, which means (90 - 0.573) 89.427 degrees. Remember SOH-CAH-TOA from your trig class, however long ago that was; in this case we know the Adjacent (which is the vertical, i.e., the height from ground to projector) and we want the Opposite (which is the horizontal, i.e., the distance along the ground to the cutoff), so use TOA. take the tangent of 89.427, which is 99.9893. Let's assume your Vertical is, say, 58cm. So, for TOA, Tangent = Opposite over Adjacent:

99.9893 = Opposite / 58

Multiply both sides by 58:

5799.38 = Opposite

That's in centimeters, so divide by 100:

57.99 = Opposite. Your range along the road to the low side of the cutoff for low beams 58cm above the ground aimed 1% down is 58 meters. That's not very far, but it's the same for any ECE-type low beam at that height with that aim angle...projector or reflector, halogen or HID.

Plug in the U.S. aim spec for this type of low beam of 0.7% (0.4 degree) and you get 83 meters, a giant increase of 43% in seeing distance. That's the difference between the cutoff being 3.5cm vs. 5cm below horizontal at 5 meters' distance.

 

[tay]

I've had pretty decent results aiming my headlights by backing into my garage (relatively new construction with a level concrete floor) and using a laser level and a long measuring tape. Laser level has a tripod that I can just mount on the front bumper at the same level as the bulbs, then adjust it to level. Then I usually just put a trashcan in the driveway like 25 or 50 feet out, and make sure that the projectors are aimed at the correct drop below horizontal.

Yellow blur on the cutoff isn't easily avoidable without modifications. As far as I've been able to discern by playing with a pretty decent variety of projectors, the yellow is a result of the dispersive qualities of the glass used in the lens. since the index of the material varies by wavelength, so does the focal point.

yellow cutoff means that the cutoff shield is correctly in focus for the shorter wavelength blue and purple light, but out of focus for the red and yellow light. blue cutoff means that the cutoff shield is correctly in focus for yellow and red light, but blue and purple light is out of focus and is fuzzy.

Some cars have no color in the cutoff. I believe that is done by having two cutoff shields spaced about a millimeter apart, so it is in focus for all wavelengths of light. I thought that the little piece that says "LV" on it would reduce color artifacts in the cutoff, but I'm not sure.

 

[-Virgil-]

Some cars have no color in the cutoff. I believe that is done by having two cutoff shields spaced about a millimeter apart, so it is in focus for all wavelengths of light.

Or a curved cutoff shield.

 

[tay]

Or a curved cutoff shield.

Really?

I was under the idea that the curved cutoff shield is meant to sharpen the edges of the cutoff. A lot of people on HIDPlanet do custom curved cutoff shields that will give a very sharp blue cutoff the whole way around, not just in the center. This should give a sharper cutoff due to a spherical wavefront, afaik, but wouldn't reduce color due to dispersion.

I know the FX is known for having double cutoff shields about 1mm apart that effectively reduce any color from dispersion.

 

[-Virgil-]

Really?

Naw, I'm making it up just to see who'll believe me! ;-)

Seriously, yes, really. I'm thinking of a fair number of Japanese and Korean projectors that have cast aluminum or Zamac cutoff shields. Many of them are much thicker than a piece of sheetmetal. Here's a medium-recent Korean-made Hyundai Tiburon cutoff shield made of cast aluminum.

Note the curvature of the shield as a whole, and the thickness of the aluminum wall. The "NAS" means "North American Specification". The flat front wall of the cutoff shield is used to provide upward light (above the cutoff) for overhead road signs: light passing over the top of the cutoff shield hits the flat rear wall of the projector lens. Some of it reflects rearward onto the flat front face of the cutoff shield, which is thus illuminated, and this illuminated surface is projected through the lens. Also take note of the interesting cutoff-shape contour, which has an upstep and an upsweep. It's a very good cutoff shape. You can read about it in this Bosch technical paper from 1985.

 

[mrb]

Thanks for all the replies guys, I think Q2 and Q3 can be put to bed.
The lights are roughly 0.62m from ground giving lower cut-off ~62m range. I must have had them more like 1/2 of this.
I will see if I can get them set properly by a beamsetter hopefully tomorrow.

Re:Colour, I've seen some of the mods done at the planet but most seem to be adding more colour by using washers to space out the projector lens' focal point. I did have to get a third headlight as one I got was from an early production run and had a different lens, a dimpled 'blob' in the middle and I didn't want to have it being picked up as different from the other one. At least I have some spares.

You've all been very helpful as usual and hate to ask again knowing you guys are doing this in your own time but do you have any thoughts on Q1 and Q4 or should I see if a genuine proper beamset re-aim helps first?

Thanks again:grin2:

 

[-Virgil-]

Q1: Answered already (sharper cutoff = aim more crucial)
Q4: No problem as is.

 

[mrb]

Q1: Answered already (sharper cutoff = aim more crucial)
Q4: No problem as is.

Ok, I agree that 1 been covered too, and now 4 so thanks again for swift reply.:)

 

[tay]

Naw, I'm making it up just to see who'll believe me! ;-)

Seriously, yes, really. I'm thinking of a fair number of Japanese and Korean projectors that have cast aluminum or Zamac cutoff shields. Many of them are much thicker than a piece of sheetmetal. Here's a medium-recent Korean-made Hyundai Tiburon cutoff shield made of cast aluminum.

*snip snip pics*

Note the curvature of the shield as a whole, and the thickness of the aluminum wall. The "NAS" means "North American Specification". The flat front wall of the cutoff shield is used to provide upward light (above the cutoff) for overhead road signs: light passing over the top of the cutoff shield hits the flat rear wall of the projector lens. Some of it reflects rearward onto the flat front face of the cutoff shield, which is thus illuminated, and this illuminated surface is projected through the lens. Also take note of the interesting cutoff-shape contour, which has an upstep and an upsweep. It's a very good cutoff shape. You can read about it in this Bosch technical paper from 1985.

yes, but the reason that shield does not have much color is because of how thick it is. The chromatic aberrations from lens dispersion give a focal point shift that is smaller than the thickness of the shield, so the image of the shield is sharp at all wavelengths. The curvature in and of itself does not reduce the color in the center of the cutoff, but it keeps the cutoff sharp along the edges. You can make a very thin curved shield, and it will have a sharp and colorful cutoff. You can make a thin flat shield, and it will have a fuzzy (on the edges) and colorful cutoff. You can make a thick flat shield, and it will be a fuzzy (on the edges) and color-less cutoff. Or a thick curved shield will be sharp all around and not have color in the cutoff.

I do like those "squirrel finder" things. My old M35 setup had an interesting idea. The foreground limiter was chromed, and angled forwards from the verticle. Then, the front of the curved cutoff shield was angled backwards, so light reflected from the foreground limiter to the front edge of the cutoff shield, giving some slight amount of light above the cutoff. It was just enough to illuminate the reflective road signs, but not enough to cause any glare.

 

[-Virgil-]

Um...duhhhh...I made the math a lot more complex than it needs to be, for figuring out beam reach. I had my mind on using trig to look at some other aim-related factors. :roll:

All you have to do is divide (mounting height in cm) by (aim declination percentage) to get (distance to cutoff in meters):

58cm mount height, divide by 0.7% declination = ~83m distance to cutoff.

To convert aim declination degrees to percent, divide degrees by 0.573 and round:

0.4 degree ÷ 0.573 = ~0.7%

 

[mrb]

I figured it was some sort of ratio after doing the trig, I plugged the numbers into my trusty TI graphing calc from 1991 and got out in metres whatever was put in cm, so 62cm came out exactly as 62m. Nice and easy knowing the easy way now. Still remember the mnemonic we were fed from them days: Signs Of Happiness Come After Having Tankers Of Ale! :D

Been hunting for beamsetter, the nearest place said have one but had recently stopped doing M.O.T inspections and so hasn't been calibrated since early 2009 and rightly didn't want to use it.

The next place had one, I saw it big red box with window, but was part of their inpsection setup and fully booked for days.
I did get some interesting advice from them though,
"good aim is found by parking about a foot away from a wall, marking a horizontal line in line with headlights and adjusting so the higher cut-off is on or below this line."
That doesn't sound quite right or accurate enough to me so I'm still gonna try and go the beamsetter way. I will have to book it in for like 2mins of work.:shakehead

I've added a daytime control pic above, I guesstimated the sign boards from an overhead map at about 120m which seemed surprisingly far so didn't exactly go and measure but engaged cruise at lowest speed I could, and timed, at 30KMph (8.3metres/sec) took a shade under 14sec giving d=vt d=115 metres, or 375ft.:huh: My previous halogens were just slightly illuminating at this distance according to the long exposure. Does this seem plausible????
Once I get the projectors properly aimed I'll get another quick photo but fingers crossed job will be done then.

 

[-Virgil-]

Still remember the mnemonic we were fed from them days: Signs Of Happiness Come After Having Tankers Of Ale!

In the States, they invoke "Chief Soh-Cah-Toa", which is meant to sound like an Indian (i.e., Native American) name.

"good aim is found by parking about a foot away from a wall, marking a horizontal line in line with headlights and adjusting so the higher cut-off is on or below this line."

Uh...yeah, no.

 

[mrb]

OK, been using them a few weeks now, just posted a quick update, some pics above.

Fog is a new experience, I get my own personal rainbow which changes colours from the projectors.:ooo:

Although the burners are Philips CM the light on the road still seems like it has plenty of yellow/green in it, like a non CM burner and is not at all ricer blue. They've only had about 40hrs burn time though.
Retrorefective road signs only seem to "pop out" if they are white or blue otherwise as before.

I'm still undecided if it was worth all the money, I was hearing that (OEM -not kits) "...xenon low-beams are so good your high-beams will become redundant"
I have to partly disagree, I'm using high beam more now as the projector's transition at cut-off is hard to become used to as well as the nodding on rural roads
The Bixenon part is pretty darn good, completely overpowers my H7 halogen highs, 3100lm vs 1400lm I suppose.:rolleyes:
The main advantage seems the much wider field of illumination, though not many moose around these parts...

 

[-Virgil-]

I was hearing that (OEM -not kits) "...xenon low-beams are so good your high-beams will become redundant"
I have to partly disagree

I have to fully disagree. It's an ignorant, stupid statement made by people who don't know what the frack they're talking about. There is no such thing as a low beam so good it makes high beams redundant. Low beams are not high beams. High beams are not low beams. One might just as well say "Your fingers are so good they make your toes irrelevant".

 

[mrb]

I have to fully disagree. It's an ignorant, stupid statement made by people who don't know what the frack they're talking about. There is no such thing as a low beam so good it makes high beams redundant. Low beams are not high beams. High beams are not low beams. One might just as well say "Your fingers are so good they make your toes irrelevant".

That must be the same lot who've been telling every man + his dog that HID kits in reflectors are fine, they're EVERYWHERE now, saw a particularly bad PT cruser the other day, super bright blue everywhere. Not good, but owner only has 3 forward gears so obviously happy to put up with poor equipment.:crazy:

By definition really regardless of technology, if correctly aimed one type of light should not have "twice the throw" of the other, the distribution will be different, I'm just still adjusting to the characteristics of xenon and projector technology. I've got 15+ years of halogen reflector experience to update!!