In Reply to: Re: If a Little More Light is Good - posted by Dave S. on July 10, 2000 at 10:42:01:
While there are yellow versions of fog lights (was originally thought it was better for fog, most are now clear because studies have shown that with the proper beam pattern the extra light through the clear lens is better.
It is the lens pattern on the front of the lamp that determines if it is a fog light or a driving light.
Fogs have wide horizontal & downward dispersion - with almost no upward dispersion.
Driving lights are normally aimed into a condensed beam for the distance (long range high beams). But there are also other lenses for various applications.
FOGS put most light directly on the road surface in front of the vehicle - which then reflects up into the eyes of oncoming drivers - MUCH MORE SO THAN LOW BEAMS.
So whether they are properly aimed or not Fogs should not routinely be used as "additional" lights.
AND - even worse - those that do want to use them as "additional lighting" soon realise that they do not shine very far in front of the car - so are not that effective during normal weather conditions - so they decide to "aim them a bit higher". Now they are almost as bad as high beams.