Date:         Mon, 10 Aug 1998 09:41:52 -0400
Reply-To:     Lawrence Johnson <ljohnson@HALHINET.ON.CA>
Sender:       Vanagon Mailing List <Vanagon@vanagon.com>
From:         Lawrence Johnson <ljohnson@HALHINET.ON.CA>
Subject:      Re: Driving/Fog Lights
Comments: To: "Dr. Rainer Woitok" <woitok@RRZE.UNI-ERLANGEN.DE>,
          Multiple recipients of list <vanagon@vanagon.com>
Content-Type: text/plain; charset=us-ascii

Dr. Rainer Woitok wrote:

> <snip> Thus use clear glasses to send as much light as your bulb produces
> into the fog and let the fog filter out the red and blue colors and mainly
> allow the yellow part of your emitted light come back to you. <snip>

The real problem with driving through fog, is the blinding glare from the
light reflected back by the fog. Using a light frequency (yellow) which
penetrates fog, helps. Sorry Rainer, I must disagree. In foggy conditions,
brighter is not always better.

> What mainly makes foglights foglights is the special construction of the
> lens and the fact that they are mounted relatively low above the ground.

Yes, fog rarely forms near the road surface. If the fog lights are low enough
and the lens is shaped to spread light only on the road surface, then more
light reaches the road surface and less light is scattered back by the fog.
Here brighter can be better.

Larry (always in a fog)
'86 Syncro Westfalia