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Doing a xenon mod to fog and trunk numberplate lights?

noogieman

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I was thinking of doing a xenon type mod to my C43.

What electronic kit is recommended to use for front spoiler foglights?
Best quality kit vs price.
Can anyone link where to buy?

Doing my rear numberplate lights, what bulbs should I get to get the nice white shine?
Can anyone link where to buy those xenontype bulbs?
Do I need any electronic box for those trunk lightbulbs?

Do I get any malfunction error in my cluster after doing both mods?

Thanks
 
For the rear plates you need error free LEDs, drop me a PM if you like, I sell them

For the foglights adding Xenon will render them useless as the light pattens will be wrong.
 
I have done both, you have two types for the number plate

1. Festoon type which is essentially just a buld change
2. The whole light unit replaced which involves abit more work but effect is alot brighter.

as for the fogs, as KH says, they will be useless in actual fog as the white light will cancel out with the fog and you wont see a thing! because of this is left mine with standard bulbs as its the yellowness of these that helps you see.
 
I got some led bulbs to match the colour of my headlight . You need a fairly big resistor but they work fine in the fog driving last sunday proved . £40 all from ebay .
 
I have done both, you have two types for the number plate

1. Festoon type which is essentially just a buld change
2. The whole light unit replaced which involves abit more work but effect is alot brighter.

as for the fogs, as KH says, they will be useless in actual fog as the white light will cancel out with the fog and you wont see a thing! because of this is left mine with standard bulbs as its the yellowness of these that helps you see.

does festoon bulbs improve white lights than standard bulbs with yellowish shine?
do I see any improvement?
 
does festoon bulbs improve white lights than standard bulbs with yellowish shine?
do I see any improvement?

the LED festoon sold by KH will do the job nice white light
 
as for the fogs, as KH says, they will be useless in actual fog as the white light will cancel out with the fog and you wont see a thing! because of this is left mine with standard bulbs as its the yellowness of these that helps you see.

I don't get this? Why would yellow bulbs be better than white?

I DO get that the reflector/lens/bulb position would probably be wrong to get the correct beam pattern, and this would probably result in more scatter, but what has the colour got to do with it?

A genuine question, BTW.
 
I don't get this? Why would yellow bulbs be better than white?

I DO get that the reflector/lens/bulb position would probably be wrong to get the correct beam pattern, and this would probably result in more scatter, but what has the colour got to do with it?

A genuine question, BTW.

Its to do with the visual spectrum (someone else can explain this better) aswell as the light patten.

For example, I have MTECH H7s 5000k non Xenon fitted, at dusk on a cloudy day it feels like they arent even on, as the light output perfectly matches the daylight. agaist waterdroplets the reflection would be identical to the colour of the fog itself (in daylight) thus making them pointless.
 
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But fog doesn't have a colour.

Surely white will reflect/refract white, and yellow will reflect/refract yellow too?
 
But fog doesn't have a colour.

Surely white will reflect/refract white, and yellow will reflect/refract yellow too?

Fog does have a colour:

fog.jpg


Grey/white which is probably around 4500-5000k. The 'colour' comes from the sun during the daylight.
 
I don't get this? Why would yellow bulbs be better than white?

I DO get that the reflector/lens/bulb position would probably be wrong to get the correct beam pattern, and this would probably result in more scatter, but what has the colour got to do with it?

A genuine question, BTW.
In fog yellow light is better, its not a conclusion i have made up, its a fact... google it, look up lumens and light temp to start with.
 
But fog doesn't have a colour.

Surely white will reflect/refract white, and yellow will reflect/refract yellow too?

Yes, this is my point, white will reflect the white of the Xenons, thus rendering them usless. Yellow bulbs will reflect a different colour temp.
 
Think of it this way, why dont manufacturers make Xenon foglights?

Try it, fit them but do it on a private road!
 
Thank you guys, but I have to say, I still can't get my head round it.......:confused: :confused:
 
Fog is actually very fine (miniscule) water droplets in the air which will reflect any light back to it's source, so the brighter the light the more reflected light you get, and is the reason fog lights are mounted down low. Try driving in fog with main beam on and then dipped beam. The thicker the fog, the more noticeable will be the effect.
Fog lights used to be yellow, but there was minimal difference between those and white ones that they discontinued them, IIRC. Plus we don't get pea-soupers like we used to have.
 
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Fog lights used to be yellow, but there was minimal difference between those and white ones that they discontinued them, IIRC. Plus we don't get pea-soupers like we used to have.

They still are, thus our discussion earlier...
 
They still are, thus our discussion earlier...

It's all to do with luminescence, though I could never see any difference between the two myself.

------------------------------------------

There is no good reason why fog lights are yellow. Here is an excellent explanation provided by Professor Craig Bohren of Penn State University:

"First I'll give you the wrong explanation, which you can find here and there. It goes something like this. As everyone knows, scattering (by anything!) is always greater at the shortwavelength end of the visible spectrum than at the longwavelength end. Lord Rayleigh showed this, didn't he? Thus to obtain the greatest penentration of light through fog, you should use the longest wavelength possible. Red is obviously unsuitable because it is used for stop lights. So you compromise and use yellow instead.

This explanation is flawed for more than one reason. Fog droplets are, on average, smaller than cloud droplets, but they still are huge compared with the wavelengths of visible light. Thus scattering of such light by fog is essentially wavelength independent. Unfortunately, many people learn (without caveats) Rayleigh's scattering law and then assume that it applies to everything. They did not learn that this law is limited to scatterers small compared with the wavelength and at wavelengths far from strong absorption.

The second flaw is that in order to get yellow light in the first place you need a filter. Note that yellow fog lights were in use when the only available headlights were incandescent lamps. If you place a filter over a white headlight, you get less transmitted light, and there goes your increased penetration down the drain.

There are two possible explanations for yellow fog lights. One is that the first designers of such lights were mislead because they did not understand the limitations of Rayleigh's scattering law and did not know the size distribution of fog droplets. The other explanation is that someone deemed it desirable to make fog lights yellow as a way of signalling to other drivers that visibility is poor and thus caution is in order.

Designers of headlights have known for a long time that there is no magic color that gives great penetration. I have an article from the Journal of Scientific Instruments published in October 1938 (Vol. XV, pp. 317-322). The article is by J. H. Nelson and is entitled "Optics of headlights". The penultimate section in this paper is on "fog lamps". Nelson notes that "there is almost complete agreement among designers of fog lamps, and this agreement is in most cases extended to the colour of the light to be used. Although there are still many lamps on the road using yellow light, it seems to be becoming recognized that there is no filter, which, when placed in front of a lamp, will improve the penetration power of that lamp."

This was written 61 years ago. Its author uses a few words ("seem", "becoming recognized") indicating that perhaps at one time lamp designers thought that yellow lights had greater penetrating power. And it may be that because of this the first fog lamps were yellow. Once the practice of making such lamps yellow began it just continued because of custom."

Also, take a look at the following web site:
Do Fog Lights Really Work?, Alaska Science Forum

Dr. Lawrence D. Woolf
 

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