Effective Light Colour In Fog
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At one time, one of the European countries (France, I think) used to have yellow tinted headlights and fog lamps by law. At one time to drive there you used to have to fit plastic clip on yellow things over the lights (my Dad's mate used to do that to his Austin Maxi to go caravaning in France!)
I think some French cars over here had white headlamps, but yellow foglamps? So if the cars you've seen were 20 year old Renaults or Peugeots, that could be your answer!
I think some French cars over here had white headlamps, but yellow foglamps? So if the cars you've seen were 20 year old Renaults or Peugeots, that could be your answer!
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Its possible that theres a yellowy colouring due to the age of the lense and the power of the bulb, my headlamps were an awful yellow colour, all i did was upped the wattage of the bulb and got a slight blue tinted bulb, sports or ice blue 80ws, will do the trick, shines bright white.
IIRC the idea of fog lights is to be seen easier by other road users, not to see better. Correctly adjusted fog lights don't really illuminate the road ahead, except maybe the kerb about 10ft in front of the car, so IMO the colour should be as bright as possible and white is brighter than yellow. Now if we're talking Spotlights, as in auxiliary lights which come on with the Main beam, then yellow will produce less glare in fog (probably so would yellow main beams).
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Fog lights, as I understand it, should be set to pick out the edges of the road. Mine are useless though as anything other than marker lights. If I sit forward in my seat I can just see the end of the beam.
On my old Cavalier on the other hand, you could see the beam a short distance ahead, in fact they did improve visibility in the area imediatley in front of the car - just what you need for fog.
I don't buy the idea that they are there just to make a vehicle more visible to other traffic. A vehicle with only headlamps on in fog is hardly invisible, is it?
On my old Cavalier on the other hand, you could see the beam a short distance ahead, in fact they did improve visibility in the area imediatley in front of the car - just what you need for fog.
I don't buy the idea that they are there just to make a vehicle more visible to other traffic. A vehicle with only headlamps on in fog is hardly invisible, is it?
What's the point in having HID's in the main beams when they take time to warm up? Wouldn't it be a better idea to just run traditional filaments in the mains? Maybe even higher wattage bulbs with relays and heavier wiring to keep the extra load off the factory wiring?JCTH1 said:
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Proper Proper Proper Foglights will be extremley high intensity and yellow.
If youve ever looked at a street lamp in the fog and wondered why you can see it so well, you'll now know why fog lights are suppost to be yellow.
White fog lights simply reflect the mist that cuases the fog whereas the yellow can really cut through it
but, in heavy fog, you are suppost to drive with sidelights on, and fogs, much like many boy racers do, why? simply because that in thick ass fog, your normal beams will make the fog worse, at least it will seem it to you,
If you drive with sidelights on and fogs, the foglights will illuminate the road Surface and sides, enough for you to see where the car should go, yellow fogs, cut through far further
If youve ever looked at a street lamp in the fog and wondered why you can see it so well, you'll now know why fog lights are suppost to be yellow.
White fog lights simply reflect the mist that cuases the fog whereas the yellow can really cut through it
but, in heavy fog, you are suppost to drive with sidelights on, and fogs, much like many boy racers do, why? simply because that in thick ass fog, your normal beams will make the fog worse, at least it will seem it to you,
If you drive with sidelights on and fogs, the foglights will illuminate the road Surface and sides, enough for you to see where the car should go, yellow fogs, cut through far further
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That may be true, but damnit they look like wee.
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I think this is all an urban myth loosely backed up by pseudo-science.
Weak points of the argument include: - Sodium street lights can hardly be compared with yellow incandescent bulbs; the light they produce is completely different.
Things that I'd hardly dispute: -
Using your main beam can only be bad as you blind yourself with the light reflected off the fog. Dipped beam is more useful and fog lights fitted low down would be even better.
But yellow? I'd always understood the argument for yellow headlights was that they don't disrupt your dark adaptation so badly. So you get a bit dazzled but don't stay blinded for so long afterwards. I can't see how this extrapolates to them being the best to see by.
And what about high intensity? I think there are many factors, such as general lighting conditions (day, dusk or night) which would govern the degree of success. My personal opinion is that you hit the law of diminishing returns early on as you'd just increase the light reflected back off the fog droplets and not actually see any further.
Weak points of the argument include: - Sodium street lights can hardly be compared with yellow incandescent bulbs; the light they produce is completely different.
Things that I'd hardly dispute: -
Using your main beam can only be bad as you blind yourself with the light reflected off the fog. Dipped beam is more useful and fog lights fitted low down would be even better.
But yellow? I'd always understood the argument for yellow headlights was that they don't disrupt your dark adaptation so badly. So you get a bit dazzled but don't stay blinded for so long afterwards. I can't see how this extrapolates to them being the best to see by.
And what about high intensity? I think there are many factors, such as general lighting conditions (day, dusk or night) which would govern the degree of success. My personal opinion is that you hit the law of diminishing returns early on as you'd just increase the light reflected back off the fog droplets and not actually see any further.
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unfortunatley, it isnt an urban myth, yellow fogs will cut through further, white light reflects the water particles suspended with the fog wheras the yellow also does but not as badly, the beam goes further, think back to science and using light filters. White on white creates a diffusion effect, use a differnt colour light and it still diffuses but not as badly
the whole idea is that the main lights light the road ahead, wheras fogs light up the road itself, so ideally you want to be looking at the road itself in fog rather than 10 feet ahead of you
the whole idea is that the main lights light the road ahead, wheras fogs light up the road itself, so ideally you want to be looking at the road itself in fog rather than 10 feet ahead of you
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I don't find it unfortunate. I well remember science as I studied Physics. I don't think I remember it the way some others do though.
This 'yellow light' from incandescent bulbs is hardly just yellow light and even if it was it would reflect eqully well as white light.
This whole diffusion/reflection stuff does not apply with the size of particles in fog.
This 'yellow light' from incandescent bulbs is hardly just yellow light and even if it was it would reflect eqully well as white light.
This whole diffusion/reflection stuff does not apply with the size of particles in fog.
so guys have you come to a conclusion yet. Do i go for blue fog lights or yellow ones.
The yellow ones will emit more lumens over the blue ones but if it aint going to make much difference i might aswell match the dipped ones to the fogs and have yellow mains for that extra lumens.
jcth1
The yellow ones will emit more lumens over the blue ones but if it aint going to make much difference i might aswell match the dipped ones to the fogs and have yellow mains for that extra lumens.
jcth1
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if you want effective fogs, yellow, if you just want fogs that look interesting, blue
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and if you want a complete explination as to why yellow fogs are what you want, click here
it explains EVERYTHING to do with why they work better, and sorts out the bits i got wrong. urban myth. I think not
http://www.danielsternlighting.com/tech/lights/light_color/light_color.html
and it's all to do with wavelengths and selective colouring. Yellow has a longer wavelength, and your eye can pick it out far better,
physics
it explains EVERYTHING to do with why they work better, and sorts out the bits i got wrong. urban myth. I think not
http://www.danielsternlighting.com/tech/lights/light_color/light_color.html
and it's all to do with wavelengths and selective colouring. Yellow has a longer wavelength, and your eye can pick it out far better,
physics
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I have to smile. I think this is just more of the stuff that spreads the myth.
I've got an idea. Why don't you point this all out to DaimlerChrysler and tell them you could have saved them millions of Euros with all that laser infrared vision stuff and just fitted yellow bulbs.
I've got an idea. Why don't you point this all out to DaimlerChrysler and tell them you could have saved them millions of Euros with all that laser infrared vision stuff and just fitted yellow bulbs.
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