RE: add fog lights
 

That's what I always believed as well:

"Traditionally fog lights are yellow, and the reason why is the subject of some speculation. A common claim is that they need to be a single color light rather than white light, to minimize dispersion as the light hits the water vapor and scatters in different directions."

"The problem with this idea, which sounds plausible scientifically, has to do with the size of the water molecules in fog. The molecules of water vapor are large enough that dispersion does not occur in any meaningful way, making the wavelength of the light irrelevant. It is possible that the first car companies to utilize fog lights were not aware of the impact that the size of water vapor molecules would have on the dispersion, and so believed that by choosing yellow lights they were minimizing the blur the fog lights cast. More likely is that yellow was chosen because of its connotations in the West with caution. Yellow lights and yellow signs are used to indicate that a driver should slow, look for obstacles, generally use increased levels of caution -- precisely the activities one wants other drivers to exercise when driving in heavy fog."

http://www.wisegeek.com/what-are-fog-lights.htm


Additionally, if you check with the major name brand manufacturers of quality fog lights, you will find that the vast majority are white, and that the amber ones are now a distinct minority.



I'll have to do some research, as I'm seeing 60w/33w, which would be less bright for the driving light than OEM 9006s, and 100w/85w & 130w/90w, which would be too much for the blinker. Might require modding the back of the blinker housing with a second smaller socket. Still an interesting original idea.

RE: add fog lights
 

http://www.newton.dep.anl.gov/askasc...9/phy99xx4.htm

My understanding is that it is important for fog lights to be one color
(rather than white, which is all colors) because the different
wavelengths(colors) of visible light scatter off the fog droplets
differently. This phenomenon is known as "dispersion," because the
different colors of light in an image will separate from each other,
causing the image to "disperse." If you illuminate the road with only one
wavelength (color) of light, the images of the objects you see will still
become somewhat blurry because of the scattering of light by the fog, but
at least you won't have extra problems from dispersion. So, if we want to
use just one wavelength of light, which wavelength should we use? It turns
out that light with short wavelengths scatters more than light with long
wavelengths (short to long: violet, indigo, blue, green, yellow, orange,
red). So, a long wavelength light will be best. There's another thing to
consider, too: our eyes are not equally sensitive to all colors. It turns
out that we are most sensitive to yellow and green light. So, our best
compromise between sensitivity for our eyes and a long wavelength for least
scattering is yellow light.

And if you click the link at the bottom of the thread it basically says there is no truth to yellow light being better then white light.

Here is another link, with a link to the government site seeking more info about all lights mounted up front.
http://www.garageboy.com/fahrt/fog.html


To further disperse fact from fiction. Not all fog lights are white light, even if they look white. They are so "white" that they have a blue hue to them. So are they actually white or are they blue light? Remember the long wavelength color spectrum listed above? Blue, green, yellow... Could it be the blue color that is making the "white" fog lights work in the fog? Remember the single color works better then all colors, and white is all colors in the light spectrum. Could it be the blue hue of the "white light"?

Regardless what color you choose to use. In order for your fog lights to be effective, they need to be more powerful then your headlights. If you have super birght headlights, your little 23wattt factory fog lights aren't gonna do crap. This tips into the issue of people driving with thier fog lights (regardless of color) on during clear days. All they are doing is creating a hazardous situation for themselves. As the garageboy link points out.

I still prefer amber colored fog lights. It's a habit I picked up when I lived in the Rocky mountains at 9,100 feet. The only light that cut through the blizzards was amber. Since I now live in the Midwest and every spring/fall we have severe fog. I pass all sorts of people with "white" fog lights on my way to work in the morning.

RE: add fog lights
 

I saw that SPY versus SPY article at the Newton site, but if you want a more detailed scientific explanation, you can check here (it also speaks to the "blue" lights):

http://www.madsci.org/posts/archives...4187.Ph.r.html

Specifically, I think what he states about "headlights would appear very red to oncoming traffic" seems to clinch the matter.



As magtec initially mentioned, we’re referring to dual–filament bulbs in regards to driving lights, not fog lights. In the example I mentioned, the driving lights would be 60w and the blinkers would be 33w. However, I don’t think the 60w would still be bright enough either.



Don’t get me wrong, I do too ! But apparently they are not an advantage.