Xenon and fog light colour mis match

Daveotto

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First thing I am not 100% satisfied with, a very minor niggle but enough to make want to do something about........with xenons you do not really need fog lights but used them for first time today and you can really notice the difference in light colour of the fog lights which look very yellow compared to the DRL'S and xenons. Would have been far better if they had provided a better colour match fog light bulb for those with xenons

Think someone else has mentioned this on this forum and has managed to source suitable replacement fog light bulbs but I could not locate the post, would be grateful if someone could repost the matching bulb spec and where they bought from.
 
"This behaviour is by design." It's something scientifical-like that I'm not able to explain but both the color and the angle of the lighting is optimised for specific weather and lighting conditions. Hello light is good in fog but not in the dark, white light is good in the dark but not in fog. If you use your xenon lights in heavy fog the bright white light will be reflected by the moisture in the air.

I'm far from an expert, but I think replacing the bulbs in the fog lights is counter-productive.

GS
 
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"This behaviour is by design." It's something scientifical-like that I'm not able to explain but both the color and the angle of the lighting is optimised for specific weather and lighting conditions. Hello light is good in fog but not in the dark, white light is good in the dark but not in fog. If you use your xenon lights in heavy fog the bright white light will be reflected by the moisture in the air.

I'm far from an expert, but I think replacing the bulbs in the fog lights is counter-productive.

GS

That does make sense actually. Yellow light will cut through fog better, just like the yellow light from the sun reaches us directly. The blue part of the sun's light gets scattered by the atmosphere and gives the sky it's blue colour.
 
Well at least this is something S3 owners won't have to worry about - no front fog lights at all on them! :D
 
Yeh - it makes sense the way it is I think. I'd never have my fog lights on unless it was foggy (and hate people that leave them on.. grr!), and if it is foggy, I want them to be functional, not look pretty :p I've noticed that they stay on with the DRLs as part of the coming home / leaving home lights though, but I don't really need this feature so will probably turn it off.
 
Yeh - it makes sense the way it is I think. I'd never have my fog lights on unless it was foggy (and hate people that leave them on.. grr!), and if it is foggy, I want them to be functional, not look pretty :p I've noticed that they stay on with the DRLs as part of the coming home / leaving home lights though, but I don't really need this feature so will probably turn it off.
Regards the coming home function - is there a way to disable the fog lights only with this? Just seems a little odd that they come on as well as the main headlights. With my old TT using this function they didn't..
 
For those of us that can remember that far back but there was a fashion at one stage of fitting yellow tints over a headlamp, or indeed yellow fog lights. I'm not sure if it was for the same reason though or purely because it was a fad...
 
I agree, but I don't use the coming home/leaving home lights anyway. Before I turned them off I did think it was odd that the fog lights came on as well. Can't say the colour bothers me (or understand why it bothers anyone else) though.
 
This coming home / leaving home function has always been a bit of an odd one.

Mercedes-Benz have had this function for years on most of their range from the C-Class up. Typically, it's the side lights and fog lights which come on when locking / unlocking. However, when unlocking, the lights all turn off as soon as you open the drivers side door, (guessing it's assuming you've made it to the car safely and don't need the lights on any more).

Volkswagen vehicles seem to have the side and dipped beam lights used for the coming home / leaving home, (not fogs).

Oddly, my neighbour opposite has a '12 plate A6 S-Line with Xenons and his coming home / leaving home function seems to just keep the LED front and tail lights on, (no dipped beam / fog lights used). .
 
That does make sense actually. Yellow light will cut through fog better, just like the yellow light from the sun reaches us directly. The blue part of the sun's light gets scattered by the atmosphere and gives the sky it's blue colour.

Well, the LED lights are whiter than Xenon so it will be interesting to see how they deal with fog.
 
Regards the coming home function - is there a way to disable the fog lights only with this? Just seems a little odd that they come on as well as the main headlights. With my old TT using this function they didn't..

Headlights don't come on - not on xenon models anyway. Just fogs and DRLs.
 
"This behaviour is by design." It's something scientifical-like that I'm not able to explain but both the color and the angle of the lighting is optimised for specific weather and lighting conditions. Hello light is good in fog but not in the dark, white light is good in the dark but not in fog. If you use your xenon lights in heavy fog the bright white light will be reflected by the moisture in the air.

I'm far from an expert, but I think replacing the bulbs in the fog lights is counter-productive.

GS

Totally agree! I understand the colour difference looks silly and if I'm honest I would love to change mine to a better match. The reason for not changing them is as the quote above. The reason they are that colour is for better vision in fog and quite rightly white will just make it harder to see. I'll be leaving mine as I often drive a road over moors which gets real bad fog. To the point of turning off dipped, using fogs only is quite common. One bulb I'd like to change for a closer match is the cornering one. Can't see the reason for this being so yellow.
 
Well it does look better at the right, doesn't it :

dsnc.jpg


or here :

s7ar.jpg
 
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Forgot to follow up on this, t8ups provided some colour matched H8 bulbs and have been using over last couple of months and had no issue with visibility on some pretty foggy days, and when coming to unlock the car in the work car park on the way home, they do look so much better than the old colour mismatched version.
 
I am keen to change my fogs to LED too, a local supplier quoted me on an after market set. My problem is that a friend of mine pointed out that there these could throw a few problems in the future like overheating etc.

Can anyone vouch and say that aftermarket options are suitable?

Also, does Audi have OEM versions?
 
I am keen to change my fogs to LED too, a local supplier quoted me on an after market set. My problem is that a friend of mine pointed out that there these could throw a few problems in the future like overheating etc.

Can anyone vouch and say that aftermarket options are suitable?

Also, does Audi have OEM versions?

Since the LED headlight pack doesn't have fog lights I would guess standalone OEM fog lights aren't available.
 
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I hope you guys are not going to be cap on backwards people and drive around with fog lights on when there's no need?

I thought it was only legal to use them in reduced visibility?