What is the function of yellow headlight lenses?

[JonT]

Just wondering--thanks.

[Jim Sims]

To protect sensitive French eyes. Jim

[nostatic]

bling. Although I suppose there is an argument that the yellow doesn't reflect as much in fog, giving better visibility.

[dd74]

Better visibility in snow, I think.

[ted]

Last I heard they are more common in France.
Some have called them surrender lens.
Perhaps so the French could surrender at night?

Agree, amber lens have been thought to help in reduced visability.

[Randy Webb]

Pretty funny.

The yellow filters out blue wavelengths and was thought to reduce backscatter and eye strain in rain, fog, or snow. Later experiments could not confirm that. However, some raptors (hawks, etc.) do have yellow oil drops in their eyes to filter as above -- apparently.

[Paul Franssen]

I removed my previous comment (having to do with "French" and "yellow") because of lack of Porsche content (nice to have an "edit" feature), and because I don't want to eradicate an entire people for the stupidities their barely elected leaders do to the rest of the world, be they friend or foe.
Yellow headlamps used to be (up until at least 20 years ago) compulsory in France. You could tell a French car from a mile away because of the headlights, not that the French need yellow headlights to stand out.

[Quicksilver]

Your eye isn't designed to see blue light very well. The xenon hid lights put out a lot of light but it isn't towards the range where your eye works well. Blue light is more effective at killing night vision too. Red and yellow lights are used to provide light that won't impact your night vision. (ask a fighter pilot what color lights are in the ready room).

I personally have 80/100 yellowish 'all weather' bulbs in my car and I find that it gives me better depth perception at night. Unlike the white 80/100 bulbs, I find that no one ever flashes their high beams at me so I'm not pissing of other drivers.

Until recently I had amazingly bad astigmatisms in both eyes (thank god for lasers!) and the glare from the stupid blue lights really bothered me. It doesn't bother me so much but it pointed out that if you can throw more light out there without bothering someone else then that is a good thing.

Wayne

[turbocarrera]

Yellow helps a bit in fog and snow, but not alot. I suppose if you encounter alot of fog/snow where you live it might be a good idea to have yellow lenses on your fog lights but I would never put them on the headlights.

Seriously, those comments regarding the French are amazingly ignorant.

[Quicksilver]

"How many frenchmen does it take to defend Paris?
- No one knows. It's never been attempted..."

My friend that lives halfway between Cannes and Nice thought that one was hysterical. (She did think the "Freedom Fries" thing was stupid as french fries aren't French.)

They were joking. It may annoy you but they realize that they are joking so it probably isn't ignorance.

BTW- You should hear what the French have to say about Americans!

Wayne

[sundaypunch]

Originally posted by Paul Franssen
I removed my previous comment (having to do with "French" and "yellow") because of lack of Porsche content (nice to have an "edit" feature), and because I don't want to eradicate an entire people for the stupidities their barely elected leaders do to the rest of the world, be they friend or foe.

Unfortunately the French bashing is a common occurence on this and other 911 bulletin boards. Most of us realize that we have fellow board members from that area of the world that are likely as proud of where they live as we are. Just so you know Paul, it really is a small percentage of us that feels that way (let alone feels the need to vocalize it in a Porsche forum). I won't apologize for others, just say that it's embarassing to see people reinforcing the "rude American" stereotype.

As for the lenses, I've heard that they really cut down on the amount of light thrown. I do think they look great on the older cars although I don't believe they are legal where I live.

[cegerer]

Read it from the headlight guru himself, Daniel Stern:

http://www.danielsternlighting.com/tech/lights/light_color/light_color.html

And my obligatory French joke:

[bigchillcar]

speaking as someone with some french heritage, it doesn't actually bother me...guess i'm just too laid back. cegerer...that google joke made me almost bust a gut! hysterical!
ryan

[Paul Franssen]

Yeah, guys, never mind and thanks...truth is I indulge in some french bashing of myself, from time to time, I know very well how the French are, and yes, they can be a Pita but if there's One thing gets on my neRves, it is narrow-minded Stupid plain nationalism of the CHiraq-"joke" typE...really!!!... But I promise to try to keep down my temper and be an honest, straight Porsche fan. And, yes, I do often defend "America" against European snobbery, so ... Peace!
P.S. To ensure I keep my promise of Porsche content, check out the capital letters in above text, in sequence

Yellow headlamps look soooh old-fashioned nowadays...

[island911]

Originally posted by sundaypunch
. ... I won't apologize for others, just say that it's embarassing to see people reinforcing the "rude American" stereotype.
. ...

I hate to say it, but no matter how hard we Americans compete with the French on "Rude" .. .de-frogs have got us beat.

As for the yellow lenses; I think they are to make the statement: "I'm different. . .just like everyone else."

[Randy Webb]

"defend Paris?"

- Also, the city fathers of New Orleans repeatedly avoided defending it - the city might be damaged and it was better to just surender.

I'm very glad to have grown up in a French culture however.

Also, it looks like those yellow lenses helped them see thru the BS the Bushies fogged the air with on invading Iraq. I am not saying it was not a good thng to remove Soddom from power, but it is quite a mess over there now.

Back to light: Your eyes sees blue just fine and can obtain higher resolution with blue than with yellow. But next to blue is UV which can and will damage the eye.

Tidbit: Honeybees can see in the UV fine and flowers are even more beautiful in the UV.

For more info read:
Rodieck, The Veretebrate Eye
Rose, Vision -- Human, Electronic and Photographic

and for a great tour of ergonomics and human factors type info, visit the library at Wright-Patterson AFB.

Don't confuse this with the Army's nattick facility where the sport among the scientists is see how long it takes to fry 8 grunts in an APC....

[Zeke]

"What's the function of yellow headlight lenses?"

At this point, just to do something to your car (maybe to identify with Europe). To me, same as side script.

BTW, I've been thinking about getting some, but at a hundred bucks, I should probably be giving a little more thought to suspension bushings, etc.

[dd74]

There's nothing better than an R5 Turbo or Alpine with yellow (amber, really) headlights...gorgeous stuff.

BTW: never met a rude Frenchman - not in Paris, at least. If you even attempt to speak French, they're greatly accomodating and patient.

[Two Oh]

Last summer I was riding around Paris in a taxi. The driver smelled so bad I told him I would give him a fiver if he would run over a skunk.