Lighting

I am predicting this will someday become a discussion so I hope to nip it in the bud before it gets out of hand like the HID headlamp threads.

MAIN POINTS
1. Fog lamps are for bad weather use only.
2. How do fog lamps work?
3. HID is bad for fog lamps.
4. How to reaim your fog lights.
5. Is yellow really better for fog lights?

Enjoy, and ask more questions if you're still foggy. Wow, didn't see that pun coming.

Lighting

Fog lamps are designed for BAD WEATHER ONLY. If you use your fog lamps for normal driving, yes you will light up the ground right in front of you so you can see that, but that bright spot right in front of you will cause your pupils to shrink which means you cut down your long distance visibility which is dangerous. Fog lamps were designed for safety.

In Bad Weather: Below about 30mph, use fog lamps only.
Above 30mph you may turn on your low beams & fog lamps for longer distance visiblity.
It is illegal to use high beams at the same time as fog lamps and your car should not let you do this anyhow.
Use judgement. If you can't see, slow down or stop.

Fog lamp bulbs are high wattage. They are typically rated for 200hrs of use. Comparably, low beam bulbs are rated for 1000-1500hrs. Another reason to only use fogs sparingly.

Fogs are mounted low and typically in the bumper which is prone to bumps and vibration. All of this destroys the aim of fog lamps. If the aim is bad you are probably blinding oncoming traffic. So use fogs in Bad Weather Only to avoid blinding people. Read on for proper aiming.

Fog lamps only light up about 30ft in front of the car and the driver can't see most of this area anyhow. You should be looking downroad when driving in normal weather, not right in front of you. So only turn them on in bad weather.

Lighting

Fog doesn't really come all the way to the ground, it hovers 12-18inches above the ground.
Your low beams are mounted in the fog zone. Which means the low beam light hits the fog/rain/snow and reflects a ton of light back to the driver creating the "white wall" effect.
Fog lamps are mounted low so they are free to illuminate under the fog. Also, they hit the fog particles at a different angle so not as much reflects back to the driver.

Fog lamps are designed to produce a low and very wide beam. This gives you immediate visability of a huge area up to 30ft in front of the car. But that's it, they don't go much farther than that so it dangerous to drive at high speeds with just fog lights because you don't have down road visability.

Lighting

There is a big argument here so I will leave this up to personal opinion. But MOST drivers will experience the same "white wall" effect from HID fog lamps as they do from their low beams during bad weather.

Intensity is the main culprit to blame for the HID no-no in fog lamps.
HID bulbs are extremely intense compared to halogen and generally have a very white color.
Your fog lamps are aimed slightly down to illuminate the road in front of you and prevent reflections back to the driver.
But HID is so intense that it will often hit wet, black pavement causing nasty reflections back to the driver. Also, HID is more prone to stray light which can hit fog and bounce back to the driver.

But what about my 3000k HID foglights you say?
Well, these are still HID, aren't they? They are still intense regardless of the color.

My opinion, stick with halogen.

R33P3R007

hey wuts with making my posts dissapear? its not my fault you didn't posted these all at the same time.

Lighting

Ok, its been a while since you checked the aim of your fog lamps, if you have ever done it. But you want to make sure they are aimed properly so they do their job.

Remember that general road vibaration is all that is needed to through your fog lamps out of aim. They are also mounted in the bumper which gets bumped.

Fog lamps are easy to aim compare to headlamps (but headlamps aren't really that hard either .

1. Park your car on a flat surface 25 ft away from a wall that is at the same height as your car. Keep the car on to keep any air suspension/auto leveling active. (I don't think this is an issue for the Cobalt, so turn the car off but make sure the battery doesn't die. You shouldn't be doing this that long anyhow.)
IF YOU DO THIS IN A GARAGE WITH THE CAR ON LEAVE THE GARAGE DOOR OPEN.

2. Measure the height from the ground to the center of your fog lamp.

3. Go to the wall and subtract 4 inches from this height.

4. Now aim your foglamps so they line up at this hieght all the way across. Ususually just need a torx head screwdriver. Crawl around the bumper to take a look.
The fog beam pattern is flat and wide, so there is no left/right aiming needed, just up/down. See the pic.

memphisr24

If you ask me, foglights don't do **** unless you have good quality ones.

Story Time:
I have a house in upstate ny, (winding roads, farmland, country) and one night it was extremely foggy. I turned my fog lights on, it did not make a difference. I then shut my headlights off and kept the fogs on, same thing, I could see a little better, but not much. I'm either gonig with HID's in my foglights or the LED's that they have on ebay which look pretty sweet too.

Lighting

The short answer, NO. You can use whatever color you want, but white or yellowish white is generally still considered best because it is cool on the eyes. Sometimes HID white/blue can be harsh on they eyes. (Another reason to stick to halogen for fog lights).

Some physics/optics background.
Water (and all solids, liquids, and gases) absorb light differently at different wavelengths. Light can be considered a wave and each color of the rainbow corresponds to a specific wavelength. Remember ROYGBIV from science class? Red, orange, yellow, green, blue, indigo, violet. Red has a long wavelength, violet has a short wavelength. Yellow's wavelenth is longer than blue, so it was theorized that the water droplets would be less likely to reflect the light back at you. This is complete BS. Water droplets are huge compared to light (only 400-700 nanometers). So water reflects everything.

For the longest time France required everyone to use yellow low beams during the winter to increase contrast and visibility. This has since changed as they adopted United Nations ECE regulations like the rest of Europe (and Canada now too).

Research by SAE and NHTSA (National Highway Traffic Safety Administration) have concluded that it doesn't really matter what color fog lamps you use. What matters more is location (low on the car), proper aiming, intensity, and proper use.

How do you know all this stuff about fog lights you ask? I am an optical engineer for a major German automotive lighting supplier. I work with this stuff everyday.

Lighting

I'll agree that quality is a huge factor in all auto lighting. Fog lights also depend on vehicle placement. They have to be below 18inches above the ground to really do anything. So tall ass trucks and Mustang GT's and so on, don't really have optimal fog light placement. (The Mustang's are right next to the low beam.)

I'm still gonna say that quality halogen fogs are still the best way to go. I would stay away from LED all together. No LED fog light will equal the output of halogen and especially HID. LED's present extreme design challenges, including requiring many LEDs and high heat, which is why no OEM has come out with an LED fog. Note that Visteon will supposedly have the first all LED OEM headlamp in production in 2007 and Hella by 2008. If big time research companies like Visteon, Hella, Bosch, Valeo don't have a good LED fog lamp in their aftermarket division yet, you can bet those things on Ebay are crap.

For quality, I would keep my focus on fog lamps from reputable aftermarket divisions of Hella, Visteon, Valeo, Bosch, PIAA, Pilot. These brands will generally produce a good beam pattern. So choosing one usually comes down to styling and mounting options.

Ciscoe.SS

So is yellow better or not????
I'm about to grab a set of yellow fogies but I'm debating on getting some xenon blues my balt is white so idk what would look best.


Any suggestions

NiceBaltSS

iTrader: (5)

5 year old thread reborn ftw lulz!!!

DiabeticKripple

iTrader: (2)

holy old thread batman

TommyP

iTrader: (2)

Yes, yellow is the best functional color for fogs.

And where did this thread come from? I didn't even know it existed. Some good info in here

DaBuzzard

If all you care about is how they look, go with whatever you want (no blue or red, certain people take great offence to that ) but if you want to see better in fog / rain / snow, plain old halogens will do the trick, something around 5k in colour temp.

I'm sure the op has long since moved on but the info he presents is spot on, should be a sticky imho

mkulrey13

iTrader: (39)

5,000k HID Setup for fogs will out do halogens and not have any issues!

sponge14

Well at least the guy knew enough to SEARCH before making a new post. I wish I could say the same for the 2.0 Performance forum where everyday there's a new ZOMG WHAT TUNEZ IS BEST?!?!!? or I NEEDZ A NEW INTAKE WHICH IS THE BESTORZ?!?!?!

mkulrey13

iTrader: (39)

Zomgz cat or catless??

sponge14

LOL true, can't forget I NEEDZ A DOWNEDPIPEZ FOR MY CARZ WHAT BRANDZ THE BESTEST AND DO I STILL NEED KITTY LITTER IF I GO CATLESS?