Pointing fog lights up completely defeats their purpose, because then they just light up the fog in front of you making it impossible to see through...They have to be yellow or white (not blue), and cannot create glare to other drivers, i.e. pointed down at the road, not pointed up so others are blinded by them.
I love curve illumination lights. Very nice, especially turning into dark streets. Everytime I get into a car without one, I wonder for a split second if my headlights are turned on. I wish there is a way to retrofit one into a Bolt.Just rented a Hyundai i30, and instead of fog lights, it has corner lights that activate based on steering angle - turn right, and the right front corner is illuminated more, turn left and the left is. More useful than fog lights in my opinion.
It's always possible that this is just a psychological thing, but it's always seemed to me that yellow fog lights cut through the fog a bit better than white headlights.Modern headlight design has made fog lights completely unnecessary. If you look at the the headlamp cut off pattern up on a wall in front of you (garage wall will do) you will see a cut-off no more than 3 feet high. While driving down the road on a foggy night this type of lighting will perform far better then old fashioned fog lights.
Almost all factory-installed or dealer-optional fog lamps, and a great many aftermarket units, are essentially useless for any purpose, especially for extremely demanding poor-weather driving. Many of them are too small to produce enough light to make a difference, produce beam patterns too narrow to help, lack a sufficiently-sharp cutoff, and throw too much glare light into the eyes of other drivers, no matter how they're aimed.
Good (and legal) fog lamps may produce white or Selective Yellow light—it is the beam pattern, not the light colour, that defines a fog lamp—and most of them use tungsten-halogen bulbs though there are some legitimate (and a lot of illegitimate) LED fog lamps beginning to appear. Xenon or HID bulbs are inherently unsuitable for use in fog lamps, and blue or other-colored lights are also the wrong choice.
If you want fog lamps because of how they look on the car, go for it.
If you want to increase visibility in foggy conditions, save your money.