What sort of setup would you use to light basic headshots, like for someone's business cards, etc.?
It's boring and uncreative, but there is a meaningful difference between doing it well and doing it poorly.
It's called 3 point lighting, anon.
Key light is usually the brightest and is used to illuminate the face
Fill light is not as bright and is used to fill in the shadows on the other side. This keeps the image from getting to contrasty with one side of the face bright and the other in complete darkness (not good).
Backlight is used to separate the subject from the background. Sometimes there even can be a slight halo around the head if the light is intense enough. A strong backlight is important if you're using a green screen because otherwise the subject might blend in with the screen too much.
Like this anon says, simple and effective. Just don't forget your backlight, why do people always do that? Makes such a difference.
I love it when in movies they do the super strong back of the head light, they seem to do that all the damn time now. Like the top of their head gets blown out. Flashbacks seem to have a lot of that.
I guess a lot of people think "Why do I need a light from the back? I guess it's optional"
It's really important for adding depth in a photo too. A portrait will look flat is there is a bunch of intense light concentrated sraight at the subject's face.