Driving with xenons in the fog

[richtung]

Evening Guys,

On the way home today in Manchester, there was a fair bit of fog with visibility just over 100m. Plenty of people with front fogs and one or two with rear fogs on (no need for rears!). Anyway, i turned my fogs on with the xenons and couldnt see any (noticable) difference so swtiched them off.

As i got closer to home, the fog closed in and reduced visibilty to 80m or so. I tried the front fog lights but again, only a marginal difference.

Is there any point in using front fog lights if you have xenons? Obviously, in extreme fog where visibility is down to 10m or so, i reckon fogs would make a difference but what about with 50-100m visibility?

thanks

Rich

[bacillus]

By coincidence, I was commenting to my wife tonight in the Manchester fog that in my experience using front fog lamps when you have xenon headlights is pointless. 

[scottm72]

again I have xenons and agree, they are pretty useless
the rear fog IS usefull though to stop people ramming up your butt

[stealthwolf]

Remember what fogs are for - they have a wider beam that's designed to penetrate fog. They are there to help you see the kerb and only a short distance in front of you. I suspect you would notice a big difference at 50yrds or less, though you can start using them from 100yrds visibility.

[RedRobin]

.
My car has OEM Xenons and before I made the decision to replace my foglights with LED DRL's I tested my front foglights in very thick fog. I found no significant improvement in visibility to warrant keeping them. Obviously I switch my Xenons to dipped in the fog.

[scottm72]

.
My car has OEM Xenons and before I made the decision to replace my foglights with LED DRL's I tested my front foglights in very thick fog. I found no significant improvement in visibility to warrant keeping them. Obviously I switch my Xenons to dipped in the fog.

red can you tell me how you manage to switch oem xenons to dipped beam, I cannot do this as mine are self levelling and do not have a manual dipping option ?
is it because yours are on a 05 plate ?

[marko]

oem xenons are the ultimate....
no fogs will ever be better!!!

[scottm72]

oem xenons are the ultimate....
no fogs will ever be better!!!

what ones
oem xenons
oem bi xenons
or
oem active bi xenons lol 

[rich83]

Fog lights are not for your visibility.... they are for others.

[DaveB@Vagbremtechnic]

Fog lights are not for your visibility.... they are for others.

What even fronts?

Forward looking fog lights from a design point of view should ideally be behind and lower than the users eyeline, for example mine on the aircraft are parabolically designed to illuminate from 1 o'clock ahead to 10 o'clock ahead on the left side and vice versa on the other. They're 350W and 12 inches across.

My point being you do need more better designed power to penetrate fog, lamp colour temperature is very important too.

At the OP I may suggest the fog wasn't quite as bad as you assessed, the way fog is officially measured basically means if you had 10m viz you probably couldn't see an outstretched hand in front of you. Airliners approaching at 140mph have an approach ban in most cases inside of 650m. That said I was coming up the M6 from London last night and it was pea soupy in places

Even had to slow the mighty corsa down a bit.   

[RedRobin]

Fog lights are not for your visibility.... they are for others.

....I wondered about that. Because in very thick fog they certainly won't illuminating the way ahead from the driver's point of view.

But if they are designed to be seen (as passive lights like LED DRL's) then why aren't OEM front fogs as bright as the very bright rear foglight?

Which brings me to wonder if my LED DRL's might be morre effective at being seen than OEM foglights when it's foggy. If so, my problem then would be that my DRL's switch off automatically whenever any other lights are switched on, though that could probably be changed. In balance, genuine Xenons are so much more powerful than ordinary headlights that I don't fear not being seen.

[RedRobin]

.
My car has OEM Xenons and before I made the decision to replace my foglights with LED DRL's I tested my front foglights in very thick fog. I found no significant improvement in visibility to warrant keeping them. Obviously I switch my Xenons to dipped in the fog.

red can you tell me how you manage to switch oem xenons to dipped beam, I cannot do this as mine are self levelling and do not have a manual dipping option ?
is it because yours are on a 05 plate ?

....As done with any headlight: By moving the turn signal stalk forward/back and then seeing a blue icon light up in the rev counter clock when full beam. That's such a simple question that perhaps I have misunderstood you 

[Nodz]

I think he may have thought you could adjust your dipped beam height like you can with halogens, where with xenons you can't as they are auto levelling, instead of high (full) an low (dipped) beam like you meant

[richtung]

If i remember correctly, on the Mk4, the fog lights were intergrated in the main headlight unit if you had normal (halogen) bulbs. If you had xenons, you didnt get (front) fog lights at all. Obviously, at the time, VW obviously thought xenons made fog lighs redundant in fog but on the Mk5 (with even better xenons), they included fog lights...?

on a slight tangent, further to my previous thread of idiots driving with fog lights in normal conditions, i saw a few pilocks with fogs and sidelights only and 2 cars with no lights on at all..... i give up 

Rich

[RedRobin]

^^^^
The Mk5 R32 doesn't have fogs but IIRC comes with Xenons as standard OEM.

Also the Golf R doesn't have fogs but has LED DRL's.

Lots of cars are not fitted with foglights as OEM.