Originally Posted By: HangFire
The zXe's are blue-white and have a very short life. If that's OK with you, go for it, but I find the light they produce is heavy on glare and light on usefulness- my personal impression.
Silver Stars are good all around bright lights with a reasonable, but not long, life.
The lighting industry has almost eliminated yellow/amber fog lamps due to some scientific studies on reflectivity of white light in low-mounted driving lights. However these studies are not psychometric just photometric, meaning that they did not study how drivers are annoyed by certain colors or glare versus others. See:
http://www.danielsternlighting.com/tech/lights/light_color/light_color.html
Personally, I prefer yellow/amber driving lights, and white headlights that have a sun-like color balance of red, yellow and blue in their makeup. Sadly (for me, anyway) the trend for high end bulbs seems to be heavy on the blue, eliminate the yellow as much as possible, which to me leaves a bright washed-out view of things that look more B&W than color. Bright, washed-out B&W.
The ideal amber driving or fog lamp has dichromatic or dichroic treated bulbs, not just something with a clear yellow paint. If you find the real deal it will have a rainbow or iridescent effect when you look at it. As far as I know, Osram Fog Breakers are the only yellow bulbs that have the correct coating.
how do you quote Daniel stern's site, then conveniently ignore:
Quote:
Another technique is to have a dichroic filter on the bulb or the lens. Sold under a variety of names ("Gold", "Irridium", "Ion Crystal", "All Season", "All Weather", etc.), This is an irridescent multilayer interference coating which diffracts the blue-indigo-violet light so as to separate it out from the remainder of the light. That remainder (i.e., selective yellow light) passes straight through the filter. The blue-indigo-violet light, because it is not absorbed (blocked) but merely diffracted (bent to an angle) still leaves the lamp. It does so off axis, So lamps with a dichroic filter on the bulb or lens tend to glow blue when viewed from outside the main portion of the light beam, and there can be objectionable blue haze outside the brightest areas of the beam. The irridescence of these coatings also causes or amplifies second- and higher-order filament reflections, which can cause the lamp to emit more light into regions intended to be dark for control of glare or backscatter—such as above the cutoff of a fog lamp, or into the upward/leftward oncoming-eyes zone of a low beam. In other words, with the mirrorlike dichroic coating reflecting images of the glowing filament, light goes where it doesn't belong.