The old wives' tale that yellow fog lights give you greater visibility over white or blue ones is just not true. The premise of that superstition, that yellow light waves are long enough to pass through water particles without reflecting back into the driver's eyes, is based on a misinterpretation of Lord Rayleigh's principle of light scattering. As it turns out, the water particles in fog and mist are entirely too large to have an effect on any light waves from fog lights, be they yellow, white, blue or even green.