The way my side mirrors have always been set, the side of the car takes up 1/3 of the side mirror. This is what I was taught was "correct", and I just went along with it. I read some articles on how to properly align the side mirrors, and I never saw two people mention the same method for aligning them. This past week, I was at a stop light with a curve right before it, and as cars passed in the opposite direction, I couldn't see them in my mirrors. Then it hit me: why the hell is my car taking up 1/3 of the mirror?! So I adjusted the mirrors, and now only a quarter inch of the car is visible on the inner-most part of each mirror. Visibility is quite improved, but driving home yesterday, I noticed I could still see some things in both my sideview mirror and my rearview mirror. And now that it's starting to become winter, I have to change my route from roads 95%/5% one lane/two lanes each direction to 80%/20% one lane/two lanes, so mirrors will become more important in my daily commute.
So here's my question: when you get into a car whose mirrors are not aligned properly (rental, new, etc.), what method do you use to align them? With your method, are there any areas that are still hidden? Any areas duplicated? I'm curious to see how everyone else sets them. This is more of an opinion thread, so there is no wrong answer!