Originally Posted By: Kuato
They do widen the area you can see in the mirrors.
However IMO if the mirrors are adjusted correctly you will be able to see everything you need to. (on most vehicles)
So many people set their side view mirrors so they can see the side of the vehicle. Wrong. Assuming two side view mirrors and normal binocular vision, IMHO the view at the edges of the rear view should just barely overlap what you see in the side views. Then your peripheral vision slightly overlaps the other edge of the side view. That way you can see all behind you without looking over your shoulder. There's no reason to see the same vehicle behind you in all 3 mirrors!
I've always found it's easiest to adjust either by getting someone to walk behind the vehicle from side to side, or by getting out on the highway and maneuvering to get the views you need to get things properly adjusted.
Agreed! I read a Popular Mechanics article once about how to adjust your side mirrors. I had never thought of it on my own but it works. When adjusting your drivers side mirror tip your head to the left. Put your left ear on your left shoulder. Adjust your drivers sides mirror till you can just see the rear of your vehicle. Do the same for the passenger side by tippin your head to the right. Yes, you still need to check your blind spot, but for me this gives much better coverage and makes me feel more comfortable at the wheel.