And what Candlepower do the xenon high beam headlights do ?!!
And what Candlepower do the xenon high beam headlights do ?!!
It was stated previously that HID headlights produce ~3000lm per bulb. It's not easy to convert that to candlepower, nor is it particularly useful to do so, since the purpose of headlights is to illuminate a large area fairly evenly, not a single spot very brightly.
Most cars that have HID headlights don't actually have HID high beams, because HID bulbs will burn out quickly if they are repeatedly turned off-and-on. Cars that do have HID high beams actually use a single HID bulb with a movable "eyelid" that blocks part of the beam when the low beams are engaged, and the "eyelid" is moved out of the way when the high beams are engaged.
Last edited by fyrstormer; 09-02-2010 at 12:05 PM.
This is the oldest live thread I've ever seen in any forum, must be a record, almost 10 yrs old
My Mods.. http://www.candlepowerforums.com/vb/...5&postcount=78
Hobby only, I don't do custom mods as a service, thanks for understanding.
I was thinking Xenon projectorlights, with lenses preferably.
I am curious, in what range this should be. It is easy to calculate if you have a lightmeter. And a car with projectorlights.
( I would be surprised if I would be the first to wonder the candela-figures. )
I am interested in the candlepowers, dont be surpise to find this interest on this forum .
Stern's 4-way comparison of 178mm H4 ECE headlamps, all with the same bulb, all tested on the same apparatus. Not only does the flux range from 441 to 695 lumens (695 is 158% of 441) but also this tells us nothing about the efficacy of the beam. The lamp with 695 lumens is not the best lamp presented.
What is it you are really trying to learn here?
I don't know much, but I do know how to calculate candlepower, as for headlights Lux measurement at 1 meter gives no valid reading;
Lux measurement at distance to headlight x ( distance to headlight x distance to headlight ) = candlepower
I think that is blunt to say.
Maybe you know about headlights Scheinwerfermann, but did you forget how to obtain candlepower-figures? (I can't think of any easier to obtain number about light BTW. ) Or did you just didnt read my posts?
I would appreciate a little more consideration in wording .
Yes…and? This still doesn't tell you anything about the flux within the beam.Lux measurement at distance to headlight x ( distance to headlight x distance to headlight ) = candlepower
You're entitled to your opinion.I think that is blunt to say.
(My interest is candlepower, I can't be clear enough on that. )
Thanx for the link with test-data. I pulled open several images, and conclude the following (Correct me if I am wrong) as ball-park figures:
Low beam: 10 to 20.000 candela
High beam: 35 to 50.000 candela
I find this interesting, as a decent flashlight throws 30.000cd, and specific throw-lights do over 100.000 candela.
(Hope to measure Lux from headlights someday and will post findings then.)
this report if that's the info you want.
A flashlight beam isn't even remotely comparable to an auto headlamp beam (low or high). I ask again: what are you really trying to figure out here?flashlight
Or distance in meters at which Lux-meter reads 1,0.
(Of modern-day lens-based high and low beam headlights, the average and the top-range, may it be xenon or HID. )
I assume you understand the article you referred to, can't you just give me 'more accurate' figures?
Else prove I am wrong with explicit information to make things not more complicated then they are.
NYS Vehicle & Traffic Law Excerpts Quote: 'No lamp shall be used on a motor vehicle having a light source greater than thirty-two candle power, unless such lamp is approved by the commissioner as provided by this section.' (Note: peak of 50kcd is permitted)
This limit to 35.000 candlepower was already the limit in 1976 according this article in Populair Science 1976 . At the same time in Europe car headlights on high where limited to 110.000 candlepower each.
From 1913 up to 1930 the maximum was 21kcd, but new cars with suitable fittings where allowed to use 32kcd for headlights. Here is told in 1983 the maximum for high beams was lifted to 150.000cd.
Last edited by Walterk; 09-03-2010 at 04:01 PM.
Huh?I don't know how and what this is measured
It's the intensity values for 25th, 50th, and 75th-percentile (market-weighted) headlamps through a large matrix of test points from far left to far right, far up to far down. This is why your flashlight comparison is meaningless; headlamps are required to distribute certain minimum and/or maximum levels of light to a large number of test points widely distributed relative to the lamp axis.and do not understand the meaning of the tables in your link
Not interested.Else prove I am wrong
Yeah, that language appears in many U.S. state vehicle lighting codes, most of which are many decades out of date, and were poorly written even when the lamps they were written for were current-production equipment. Under the "no more than 32cp" restriction, exactly none of the current-production headlight bulbs would be legal. Fortunately, Federal Motor Vehicle Safety Standard 108 preempts any State provisions.Quote: 'No lamp shall be used on a motor vehicle having a light source greater than thirty-two candle power, unless such lamp is approved by the commissioner as provided by this section
The U.S. limit on high beam axial intensity was 37,500 candela per side of the vehicle until 1979, when it was raised to 75,000 candela per side of the vehicle*—*that is the current limit, though everywhere else in the world the limit is above 140,000 candela per side of the vehicle. Note this is a restriction on axial intensity, not a restriction on intensity anywhere in the beam.This limit to 35.000 candlepower was already the limit in 1976
The limit in Europe has varied from 102,500 to 215,000 per side of the vehicle over the last sixty years or so.At the same time in Europe car headlights on high where limited to 110.000 candlepower each
I agree there is much more needed to compare lights concerning the distribution patterns, beam shape, spotsize, colour, angles, lumen, flux, efficiency, physical and subjective factors and others that you can think of.
For peak beam intensity candela is just right.
(It is a reference point, and after all, I can't think of anything that I judge by one single parameter. )
Er...yes, we use the candela as the unit of measurement for beam intensity at any point. Why does it seem as though you are arguing matters not in dispute?For peak beam intensity candela is just right.
The provision for high beams exceeding 150,000 cd per lamp are brand new and associated with adaptive lighting systems, so I don't think there are any...yet.it is safe to assume high beam headlights with 215.000cd exist and are in some European production cars?
Last edited by -Virgil-; 09-04-2010 at 06:41 AM.
Last edited by Walterk; 09-06-2010 at 03:51 AM.
Marduke - Solitaire...I've seen matches which are brighter AND have a longer runtime. 光陰矢の如し
Oh, no worries, I'm not going away — I'm just discontinuing participation in Walterk's silly game, is all.
If you are trying to use a headlamp as a consistent source with which you can calibrate your light meter, I don't think that's a good use for them. Scheinwerfermann was just trying to point out that whatever you are doing, that data measurement of the brightest part of the pattern isn't going to provide any useful information about the light itself. I've seen some aftermarket headlamps that had peak intensity points many many time brighter than any headlamp from the factory.
The measurement of this point, and how much light passes through it, cannot be used to determine how many lumens the particular source is putting out. Even if you had 50 of the same car, you wouldn't be able to say anything about the light sources from measuring flux in one spot.
HIDs dim with age. Ballasts may or may not feed 35.00W to the bulbs. Projectors put out different amounts of light depending on what condition they are in and how close the bulb is to the optimum focal point. Outer lenses can vary greatly in clarity and color.
I think, for these reasons and more, Scheinwerfermann would not give you a solid end-all be-all magical average number of the universe for the candlepower of a xenon high beam.
Also, I agree. This is quite an old thread. I almost think we ought to preserve it in a glass case full of xenon.
Well, if you do THAT, obviously you should make sure you run your fog lights at all times so you can see the deer in the road in front of you! And if anyone flashes you, they're just jealous of your awesome lights!
I'm interested in getting a TM11, but I have no clue what to compare it to. How does it compare to car headlight(s), in practice? Let's say you're out driving in the countryside at night and somehow the car headlights breaks down. It's pitch black and you somehow attach your TM11 to your car. Would it be a noticeable difference to the better/worse? Will it even be close? How about comparing it to one headlight? Or comparing two headlights with two TM11's?
Check out this thread: http://www.candlepowerforums.com/vb/...EAMSHOTS-VIDEO
It has images that might give you your answer.
It boggles the mind that one of the more recent posters in this subject seemingly failed to comprehend that there's an appreciable difference between the fairly simple parabolic reflector in most flashlights/spotlights (and resultant uniform/simple "hotspot-and-spill" beam pattern) is an entirely different animal compared to the composite reflector/optic arrangements in vehicle headlights that produces a highly shaped beam with varying intensities in various sectors in order to comply with both the law and desirable performance characteristics.
A cheap $20 spotlight from Harbor Freight using a H3 bulb can reasonably produce many thousands of candlepower in the center of its hotspot at 10m yet the same bulb in a car headlight assembly will likely produce a few tens of candlepower at best in the brightest part of the beam at 10m (yes, I am speculating here and might be off by an order of magnitude or more) in addition to fewer out-the-front lumens and still be considered a very good headlight.
Then again, I should just let this very old thread die.
Last edited by idleprocess; 01-19-2012 at 10:36 PM. Reason: proofreading
I apologize that this letter is so long; I did not have time to write a short letter
The actual beams produced by the Truck-Lite headlamps don't even come close to those figures. The optics, especially on low beam, are not very well engineered -- and yes, I am talking about their latest revision, not their earlier ones. It's possible they are citing source lumens rather than lumens in beam, though looking at the LED type and count in their headlamps it's more than a little difficult to agree with 1300 lumens as even a source lumen figure.Trucklite claims 1300 lumens for low, 1300 lumens for high
That is also a source-flux figure that is not necessarily linked to light flux in beam.getting close to HID 3,000 lumens