What is the PRACTICAL difference of post-facelift halogen Hellas vs non-filament HIDs - Bimmerfest - BMW Forums



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  #1  
Old 10-29-2010, 12:03 PM
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What is the PRACTICAL difference of post-facelift halogen Hellas vs non-filament HIDs

Marketing & style wholly aside (please), what is the PRACTICAL difference between post-facelift halogen Hellas vs non-filament HIDs when it comes to seeing objects in the road in front of you?

Note: I tried to get that answer from ümnitza (925-521-0577) today; but it felt like I was talking headlights as a second language as the salesperson kept launching into a pitch about (meaningless) colors, patterns, bulbs, types, colors of the side lights.

I couldn't believe the amount of time he was taking trying to explain how LED angel eyes give better light (I don't believe it one bit) and how the clear side marker light was vastly preferable to the yellow-tinted plastic (and how does that allow me to see better?). He even tried to explain that the "color" of the light helped me to see and how the sharp cutoff in the pattern was of some (unexplained) benefit.

After all that, he tried to push me to an "HID fog light kit", which, I thought to myself, if the HID high & low beams (yes, he tried to get me to use a kit of both HIDs) lights are so good, then WHY would I need HID fog lights???

In the end, I gave up trying to understand ... but I still wonder ... what are the REAL (as in PERFORMANCE, not style) differences between the OEM Hella filament halogens (which I have) and the OEM or aftermarket non-filament low-beam HIDs (which I know nothing about)?

PS: My adjusters are toast so one of my options is new headlights.
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Old 10-29-2010, 12:13 PM
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HID>Halogen

OEM>aftermarket
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Old 10-29-2010, 12:20 PM
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Originally Posted by Orxan4ik View Post
HID>Halogen

OEM>aftermarket
+1, however :

OEM halogen>aftermarket HID
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Old 10-29-2010, 12:23 PM
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Light output from HID lights is much higher. The light is also more focussed. It's also prettier.
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Old 10-29-2010, 12:43 PM
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So, is there any benefit to put HID in a facelift halogen Hella light?
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Old 10-29-2010, 01:20 PM
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I recommend this website as a very informative and well written explanation of all things related to lighting. The good thing is there really isn't a sales pitch tied to it. http://www.danielsternlighting.com/

In a nutshell:

1. HID is closer to natural light, improving visibility and reducing eyestrain
2. HID is more durable than halogen since it doesn't use a filament
3. HID is more efficient, 35W HID produces more light & less heat than 55W halogen

I believe a 35W HID also produces more light (as measured by lumens) relative to a 55W halogen

Combined, more light + higher quality light = better night visibility
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Old 10-29-2010, 02:26 PM
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Quote:
Originally Posted by bluebee View Post
Note: I tried to get that answer from ümnitza (925-521-0577) today; but it felt like I was talking headlights as a second language as the salesperson kept launching into a pitch about (meaningless) colors, patterns, bulbs, types, colors of the side lights.

I couldn't believe the amount of time he was taking trying to explain how LED angel eyes give better light (I don't believe it one bit) and how the clear side marker light was vastly preferable to the yellow-tinted plastic (and how does that allow me to see better?). He even tried to explain that the "color" of the light helped me to see and how the sharp cutoff in the pattern was of some (unexplained) benefit.

After all that, he tried to push me to an "HID fog light kit", which, I thought to myself, if the HID high & low beams (yes, he tried to get me to use a kit of both HIDs) lights are so good, then WHY would I need HID fog lights???

In the end, I gave up trying to understand ... but I still wonder ... what are the REAL (as in PERFORMANCE, not style) differences between the OEM Hella filament halogens (which I have) and the OEM or aftermarket non-filament low-beam HIDs (which I know nothing about)?
They didn't change their ways, I see. I tried talking to them years ago and was so turned off by the constant sales pitches and the ("allegedly" - here I said it) numerous small little lies.

In the end, I turned to somebody else and got the Hella OEM HID for a much higher price, but I don't care.

Here is the thing: HID gives a much higher light output. Check that Daniel web site for actual numbers of lumens.

Everything else, like you said, who cares?

Filament uses a conic reflector to throw the light into the road. HID uses a lens in a projector to shape the light into a beam and throw it into the road.

The reason for the reflector and the projector lens is 1) to concentrate more of the light into the road in order to give the driver better road illumination. and 2) to prevent the light from blinding the oncoming traffic (that's DOT law).

HID is so much brighter, that they need to cut off the light pattern at the top, so that the oncoming driver is safe. It's not for you, it's more for him and for the law.

mw
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Old 10-29-2010, 02:40 PM
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Donna, here is my finding:
I had and still have the OEM Hella lights.
When I purchased the car it had regular bulbs. The light was Ok-ish compared to other quality headlights (I have Valeo headlights on another car). Then I started to upgrade the halogen bulb itself. The light I could have was with some sort of Philips which I purchased in the UK (cannot remeber what the marketing pitch was, how many % more than a regular bulb, etc, but it was visible better).
Then, I purchased a set of ballasts (35w) with HID bulbs. This setup was eye candy and cool, but the light output was not drastic/huge compared to the Philips bulbs I had (I know some people will not like this comment and might jump in, but I drove the car and can confirm what I just said). Maybe a tiny improvement.
Then I changed the ballasts with 55w, and the light output is amazing. Literally you can see everything on the road. I don't even need the highbeams anymore (except if on the freeway by night, driving fast - the low beam HID are pointed quite low).
So, if you want HID's, you can buy the regular Hella's (or fix your old ones if you can), and get an aftermarket 55W balast kit with HID bulbs. To have as much white light as possible I would choose 4600 - 5000 color temperature for the ballast. Mine is 4600.
There are lots of explanations on the web concerning the light temperature, and I am sure (as far as I know you) that you already have read about it.

P.S. the reason I say to buy the "regular" Hella is because they are considerably cheaper than the OEM HID Hella. The outcome is the same, as long as you point correctly the lights for oncoming traffic (for both) - it's a PITA to mount the self levelling function, plus the LCM has to be coded, etc, etc. Not worth it. The beam if pointed corrctly will not blind oncomming traffic. Your lights will bump up/down when you hit irregularities on the road anyways, no matter which setup you have.
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Old 10-29-2010, 09:12 PM
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Originally Posted by 16valex View Post
So, is there any benefit to put HID in a facelift halogen Hella light?
Yes, there certainly is a benefit...a 4x benefit if my numbers are right. A halogen 12v lamp puts out about 20 lumens per watt. So, a 35w halogen will output 700 lumens. An auto HID system, however, outputs 3200 lumens.

Ideally, you'll want to replace your halogen lamp with an HID type lamp designated as "D2R" if your headlight housing has a reflector behind the lamp. If your headlight has a "fish eye" lens in front of the halogen lamp (aka projector lens), then the HID type lamp to replace your existing halogen lamp should have a desgination "D2S". To reiterate,
The Type D2S is for use with projection lens optics. Type D2R has a black stripe over part of the outer jacket, and is for use with reflectorized optics, the black stripe helping to achieve a sharper cut-off at the beam edge, reducing stray light and glare.

If you match the right lamp w/ the right optics, there should not be any unbounded glare that will come from this retrofitting. However, in the very unlikely event that cutoff is not where it should be, typically more from a reflectorized headlight than projector headlight, that black stripe over the HID lamp can be moved in/out to readjust cutoff.

Go pho it
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Old 10-29-2010, 10:05 PM
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Just noticed you were asking why the need for HID fogs. Fog lights are NOT for extra illumination in everyday situations. They are for driving in fog or severe rain. You still need fog lights.

I consider HID lights to be a safety upgrade if they are a high quality system and don't blind drivers if installed correctly.
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Old 10-29-2010, 10:43 PM
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Originally Posted by DHoang View Post
If your headlight has a "fish eye" lens in front of the halogen lamp (aka projector lens), then the HID type lamp to replace your existing halogen lamp should have a desgination "D2S"
Just for the record, yes, I have the fisheye (1) projector OEM Hellas (2001).

I've taken apart one of my headlamps (2) with the result that I think the full description is something like:
- postfacelift
- OEM 2001 BMW
- Hella brand
- Filament bulbs (aka halogens, H7, sans ballast) for both the low beam and high beam
- w/ projector
- w/ angel eyes (aka cellis rings, I think, attached to four fiber-optic cables)
- w/ orange side lamps (with an additional fifth fiber-optic cable)
- w/o self-adjusting motor (there's just the solid stalk encased in ultrasonically welded plastic)

This photo is of my headlight with a flashlight illuminating the 5 fiber optic cables.

Last edited by bluebee; 10-29-2010 at 10:47 PM.
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Old 10-29-2010, 11:16 PM
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If that's what you have, then I would just convert the lowbeam H7 to HID with an H7 base, and be done with it.

And everything else I would leave the same.

Do not convert the high beam to HID! Total waste.

Don't even think about converting the fog lights to HID. That's mainly for "bling" - (to make the fog match the color and intensity of the headlight).

But you said you broke the headlight casing, no?

mw
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Old 10-29-2010, 11:25 PM
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But you said you broke the headlight casing, no?
It turns out it's actually harder (confirmed by Mark at EACTuning) to disassemble the stock halogen Hellas than the stock HID Hellas.

I ended up breaking the non-self-leveling stalk apparatus.

I've since glued it back together ... but dunno if that will be sufficient.

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Old 10-30-2010, 04:11 AM
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Interesting thread with valid and informed comments by all.

For those that may not be aware of the 'working' differences between HID and Halogen lighting I offer the following.
This is some few years old now, but the information is none the less still correct. If anyone can post up a more up to date explanation please do.

http://intellexual.net/hid.html



Also, I can't help but think of the fact that LED's have been improving by the year and wonder, not if, but when headlights will come offered in this format. I'm sure it's just a matter of time.

Dibs on a pair of Hella LED h/lights when they hit the market.........................in 20?? They're going to be something else!!
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Old 10-30-2010, 05:12 AM
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Originally Posted by DHoang View Post
Yes, there certainly is a benefit...a 4x benefit if my numbers are right. A halogen 12v lamp puts out about 20 lumens per watt. So, a 35w halogen will output 700 lumens. An auto HID system, however, outputs 3200 lumens.

Ideally, you'll want to replace your halogen lamp with an HID type lamp designated as "D2R" if your headlight housing has a reflector behind the lamp. If your headlight has a "fish eye" lens in front of the halogen lamp (aka projector lens), then the HID type lamp to replace your existing halogen lamp should have a desgination "D2S". To reiterate,
The Type D2S is for use with projection lens optics. Type D2R has a black stripe over part of the outer jacket, and is for use with reflectorized optics, the black stripe helping to achieve a sharper cut-off at the beam edge, reducing stray light and glare.

If you match the right lamp w/ the right optics, there should not be any unbounded glare that will come from this retrofitting. However, in the very unlikely event that cutoff is not where it should be, typically more from a reflectorized headlight than projector headlight, that black stripe over the HID lamp can be moved in/out to readjust cutoff.

Go pho it
Damn DHoang! You don't have to throw a book at me! I learned a few things today, very informative and helpful. I will make sure I get type D2S not D2R. I will definitely go pho it. Is that E30 formular1 looking car yours?
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Old 10-30-2010, 05:17 AM
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Originally Posted by DHoang View Post
Yes, there certainly is a benefit...a 4x benefit if my numbers are right. A halogen 12v lamp puts out about 20 lumens per watt. So, a 35w halogen will output 700 lumens. An auto HID system, however, outputs 3200 lumens.
Correction: Standard halogen H7 bulbs are rated at 55W. The standard HID system is rated at 35W (some boost their aftermarket systems to 55W) . This translates to 1100 lumens for halogen and 2800 lumens for HID. Still a very big difference, but I think lumens don't translate linearly, that is doubling the lumens does not double the visibility. Any lighting engineers out there?

Occasionally you'll see a vendor issue halogen bulbs that exceed 55W but these are (supposedly) for off road applications only.
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Old 10-30-2010, 05:34 AM
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doubling the lumens does not double the visibility. Any lighting engineers out there?
Not a lighting engr, but I think you're correct on this one, the ratio of visbility will depend on the Kevin temperature you choose, I believe 4300 is what BMW went with on their Xenon, so if I would have gone with HID that is the color temperature I will pick give or take.
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Old 10-30-2010, 06:17 AM
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Originally Posted by bmw_n00b13 View Post
Just noticed you were asking why the need for HID fogs. Fog lights are NOT for extra illumination in everyday situations. They are for driving in fog or severe rain. You still need fog lights.

I consider HID lights to be a safety upgrade if they are a high quality system and don't blind drivers if installed correctly.
+1
Bluebee I would keep your focus to the low beams for now. Fog lights are a whole 'nother can of worms. IMHO people add the HID fogs for two reasons. One the bling factor/matching the color of their HID low beams. Two for use in addition to their low beams in normal night driving conditions so they are really not using them as a true fog lights solely for rain, fog and snow, but instead more as an additional set of low beams.

HID/Xenon
Bluebee you should go for a ride with a friend who has HIDs in their car at night even if it s not a BMW just to get an idea of the type of light HIDs emit. Its somewhat hard to describe, but I would say it is much more even light with a very sharp cutoff at the top of the beam pattern. Even if you end up deciding you don't like it or don't think it is better than halogen you will definitely see it is different.

Someone chime in with some illumination shots of HIDs.
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Old 10-30-2010, 07:00 AM
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Originally Posted by bluebee View Post
Marketing & style wholly aside (please), what is the PRACTICAL difference between post-facelift halogen Hellas vs non-filament HIDs when it comes to seeing objects in the road in front of you?

Note: I tried to get that answer from ümnitza (925-521-0577) today; but it felt like I was talking headlights as a second language as the salesperson kept launching into a pitch about (meaningless) colors, patterns, bulbs, types, colors of the side lights.

I couldn't believe the amount of time he was taking trying to explain how LED angel eyes give better light (I don't believe it one bit) and how the clear side marker light was vastly preferable to the yellow-tinted plastic (and how does that allow me to see better?). He even tried to explain that the "color" of the light helped me to see and how the sharp cutoff in the pattern was of some (unexplained) benefit.

After all that, he tried to push me to an "HID fog light kit", which, I thought to myself, if the HID high & low beams (yes, he tried to get me to use a kit of both HIDs) lights are so good, then WHY would I need HID fog lights???

In the end, I gave up trying to understand ... but I still wonder ... what are the REAL (as in PERFORMANCE, not style) differences between the OEM Hella filament halogens (which I have) and the OEM or aftermarket non-filament low-beam HIDs (which I know nothing about)?
There is a HUGE difference in performance.
I would buy a cheapee HID kit with the 55w ballasts, and the H7 bulb adapters.
I hate to say it/ write it, but if you want the cheap stuff, go to DDM, but beware the HORRIBLE customer service.

Or, get quality OEM Hella/ Phillips ballasts with some good Phillips H7 based bulbs.
Phillips ballast:
http://hidconcept.com/Ballasts-philipshella.html

Phillips aftermarket H7 re-based bulb:
http://hidconcept.com/Bulbs-Philip-ult5k.html

H7 bulb adapters:
http://hidconcept.com/Adapters-e39-ii.html

And, I think Umnitza also carries the bulb adapters too.
Not sure about the other stuff, but, IMO, most of their stuff is way expensive/ over-priced.

Cheap:
http://www.ddmtuning.com/Products/DD...ast-35W-or-55W

Also, I would look on Ebay (or equal) to find a used set of ballasts, or even bulbs...

Do you plan on replacing the headlight adjusters with EAC's aluminum ones?

And, the OEM D2S HID xenon bulb is 4300k.


Thanks!
Jason
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Old 10-30-2010, 12:11 PM
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Do you plan on replacing the headlight adjusters with EAC's aluminum ones?
I'm still weighing my options (1), hence the reason for this thread (to clear up the BS to what matters - which is only "visibility" on the road).

BTW, if your headlight adjusters are broken, I found at least a dozen options, scattered about these forums, only one of which are to buy new aluminum headlight adjusters (which are about mid-pack in the total cost).

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Old 10-30-2010, 12:17 PM
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I'm still weighing my options (1), hence the reason for this thread (to clear up the BS to what matters - which is only "visibility" on the road).

BTW, if your headlight adjusters are broken, I found at least a dozen options, scattered about these forums, only one of which are to buy new aluminum headlight adjusters (which are about mid-pack in the total cost).

These adjusters scare me.

Somebody tell me, before I break mine. Do I need to loosen some hidden something else before I try to adjust my headlights with the above allen key?

mw
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Old 10-30-2010, 01:01 PM
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These adjusters scare me.
Don't worry Matwiz, with some new ultimate aluminum adjusters from Mark and I will fix you up for life.
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Old 10-30-2010, 01:03 PM
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Don't worry Matwiz, with some new ultimate aluminum adjusters from Mark and I will fix you up for life.
Meh. With the advances in stem cell technology, all you'll need to is to spray some cells on it, and it will heal itself.

mw
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Old 10-30-2010, 10:11 PM
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This thread has gorgeous pictures (in gruesome detail) of the infamous broken headlight adjusters, in situ.

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Old 10-31-2010, 03:10 PM
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Correction: Standard halogen H7 bulbs are rated at 55W. The standard HID system is rated at 35W (some boost their aftermarket systems to 55W) . This translates to 1100 lumens for halogen and 2800 lumens for HID. Still a very big difference, but I think lumens don't translate linearly, that is doubling the lumens does not double the visibility. Any lighting engineers out there?

Occasionally you'll see a vendor issue halogen bulbs that exceed 55W but these are (supposedly) for off road applications only.
Believe it or not, I AM A LIGHTING ENGINEER, BY PROFESSION. I'm the guy that designs the luminaires and requisite optics for a given lamp source. Although my career background isn't in the automobile sector, but lighting demands for commercial buildings & parking garages, nevertheless, HID lighting got its start in the commercial building sector, not automobiles as most here seems to think. The lamps I design the optics for are still the same lamps used in HID type headlights - mainly the metal halide lamp- but larger in size. .

What most don't realize is that HID can light up four different light sources (lamp types): Low pressure sodium, high pressure sodium, mercury vapor, and metal halide lamps. Of the four, metal Halide produces greater CRI - color rendering index - than the other 3 HID type lamps. CRI is a measurement of how well colors are maintained. At night, you want red to appear to be red, not blue or grey. This helps with your ability to maintain depth perception. Therefore it (metal halide) is the best lamp choice for vehicle applications. Because HID powers one of these four lamp types, HID therefore is a lighting SYSTEM...not a lamp. A lamp is a light SOURCE. HID is NOT.

As for why I calculated lumen output for a 35w lamp (vs. 55w) was b/c I wanted to show differences in lumen output for lamps drawing similar watts (35w). It's a common industry practice to maintain similar power factors between lamps when comparing luminous flux(lumens) based on power(watts)to derive "luminous efficacies".

You're correct that lumen output doesn't translate linearly, thanks to physics, or more specifically, to Maxwell's four equations. The intensity of light is inversely proportional to the distance squared.
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