[dagenhay]

Last night I did my annual New Years Eve nite ride. I ride with a 3 level niterider on the bars and a niterider on the helmet. I ride some technical stuff at night and need as much light as possible. Problem is I live on the coast and there is often fog on the hill. Last night was the worst. About to start my descent, turn on both lights and I couldn't see the trail at all. The helmet light especially reflected the light into my eyes since it is so close. I turned off the helmet light and turned down the handlebar light and that was barely enough to get some vision but barely. Add that to the fact that it was a wet fog, making for slippery conditions and it wasn't a great ride.

So, do they make fog lights for mtb or lense covers so the fog won't reflect the light so much? Anyone else have this problem and how did you solve it.

 

[Resist]

Fog lights don't work well for cars let alone bikes. The solution is not to ride in conditions like fog. But I guess you could just make a mount for your headlight low on the front wheel to act like a fog light.

 

[dagenhay]

Looking at some car sites, it looks light fog lights don't work, as you said. Although, my conditions are much different than the typical car driving conditions. I am going much slower than a car. I never see other trail users at night in the fog and I don't have to worry about blinding anyone else. I am not going to run into a trail user stopped on the trail at night in the fog. I do know the trails I ride at night like the back of my hand. Therefore, I am only looking to light up about 20-30 feet in front of me.

Foggy conditions is not a deterrent to riding. The ride starts at about 125 foot elevation and tops at about 1100 foot elevation. As I ride uphill, I often hit fog that was not at lower elevations. Starting in the dark, I often don't know what the top of the hill has to offer until I get there. Plus along the coast the fog can come in very quick. In a 2 hour ride clear skies can turn to fog in a matter of minutes.

The theory is to mount fog lights low since fog sits 12-18 inches off the ground. So maybe a fork mount as you suggest would work. Apparently, there is no difference in visibility between yellow and white fog lights. But the low beam definitely works better than high beam.

 

[yetibetty]

Last night I did my annual New Years Eve nite ride. I ride with a 3 level niterider on the bars and a niterider on the helmet. I ride some technical stuff at night and need as much light as possible. Problem is I live on the coast and there is often fog on the hill. Last night was the worst. About to start my descent, turn on both lights and I couldn't see the trail at all. The helmet light especially reflected the light into my eyes since it is so close. I turned off the helmet light and turned down the handlebar light and that was barely enough to get some vision but barely. Add that to the fact that it was a wet fog, making for slippery conditions and it wasn't a great ride.

So, do they make fog lights for mtb or lense covers so the fog won't reflect the light so much? Anyone else have this problem and how did you solve it.

I had the same foggy thing on new years eve, but we were walking home from the pub at 3.00am through a pitch black farm(our usual night ride).
We took our DIY bike lights for the walk and it was fine on the way to the pub but couldn't see a thing when we left for the return.(due to fog not the beer)

The only thing that helped was to hold the lights as low to the ground as possible and I think that an elleptical beam will help as a big circle of light just reflects the fog but the letter box beam apears to shine below the fog.

Happy new year

 

[Jerk_Chicken]

The theory behind fog lights is that they are supposed to be mounted low, such as on the lowest part of the bumper or the front fascia of a car. The reason is because most fog does not lie on the ground. It lie 18-24 inches above the ground and above.

The fog lights are designed (from a position standpoint) to illuminate under the fog and cast light down the road. These are the more effective ones, though there are the ones integrated with headlamp clusters, higher above, that just tend to diffuse more light into the fog. Sometimes you can have a colored beam in yellow or orange and this is done to neutralize the blue light from the main headlights. Blue is shortwavelenth and tends to scatter very easily in fog, haze, or environmental pollutants in the air (think brown or amber sunglass lenses to sharpen vision) and being short wavelength, blue light also focuses before the retina in the eye, thus causing some vision problems when driving through fog. So now we have that lesson out of the way...

My thinking would be to mount a light as low as possible, like on a fork leg by the axle. That will keep the light forward of the fog, but don't expect miracles. You'd have to turn the main light off to reduce the bad scattering of light in the fog, or perhaps try and find a yellow beam or lens.

 

[2calif]

I ride with niterider minewt, and its White LEDs suck in fog. I was riding with some folks who had the older style incandescence reddish lights. They seem to cut fog great. But, it's an incandescence, which....

Maybe I should try to build a LED light with red tint (not sure what the code is), or WG with the green tint and see..

 

[CactusJackSlade]

I ride with helmet mounted and handlebar mounted. I've found that with fog (and especially dust) that using only the HB mount reduced the back scatter (the photographers term for particulates in the air that reflect light) and gave me better overall visibility.

When you have the light source at near the same level as your eyes, the light bounces straight back at you, when mounted lower (or higher for that matter) the light bounced back to your eye is softer and less direct.

That is why underwater photographers (who are always concerned about particulates in the water) have light racks that hold the light source out to the sides, not in the middle... gives better penetration without as much back scatter.

 

[yetibetty]

I have done a few tests as we have had quite a bit of fog over the last few days and yellow transparent Solarfim really does help http://solarfilm.co.uk/ just keep a bit on you and if it gets foggy hold some on the light with a rubber band.

This Glosstex stuff is also great

 

[mdsjack]

i'd go for low mounted lights and transparent yellow film on the lens for better contrast

 

[traffic002]

I work in the roadway lighting industry. We use Sodium Vapor lights for roadway lighting. It uses a yellow light with a smaller light spectrum. What it does is "cut" through better than say a metal halide which is more white light.

So when the light hits a water vapor, it reflects back. The wider the spectrum, the more light is reflected/refracted back. The sodium vapor with its limited spectrum doesn't reflect/refract as much.

The "old skool" fog lights on cars were yellow/amber. This did two things. It limited the light that was reflected/refracted from the fog. It also "lit up" the yellow center line of the road.

I've noticed that with LED lights, my yellow/amber glasses filters out a lot of the light. This wasn't the case with my halogen light. I've had to switch to clear lenses.

So the bottom line. LED lights or HID lights with its broader spectrum of light that lets you see color is no good in fog. The halogen or sodium or other "yellow" light reveals shapes better and cuts through the fog better.

...more or less...ymmv

 

[Jerk_Chicken]

traffic,

There's also another angle, and I don't know if you can shed light from your experience, but yellow to brown colored light tends to shift short wavelength blue light (>500nm) to green (>500nm), which has a characteristic of focusing sharply on the retina.

 

[mdsjack]

that's true

 

[Jerk_Chicken]

Got the number wrong: <500nm for blue, >500 for green light.

 

[Turveyd]

I've tried it, attached a torch to the QR works well, but need a method of hooking 1 up on the other side 2, 2 QR's maybe or you get a huge shadow from the wheel ofcourse.

Bars are generally low enough though, give up totally on helmet lights if you want to see your bars though.