When would a photographer want to use the "Full Auto" mode? (Original here)(In addition to her article, there are some good comments in response; you might want to check it out.) Her conclusion was:
If you ultimately want to have more creative control of your images then it’s my recommendation to say “no” to the green square.A mutual friend, Bryan Jones, mentioned in his response that he shoots in Program mode 30% of the time. Now Bryan is a brilliant guy and an expert on things optical. As a post-doc vision researcher and a freelance photojournalist, if anyone is capable of shooting without auto mode, it's him. The amount he used it surprised me enough that I thought a bit about the advantages for an advanced photographer to use auto mode. As I pondered, one reason for a knowledgeable user to use an automatic mode occurred to me. (And there are probably other reasons that haven't occurred to me.)
Those who know me know that in addition to programming and photography, one of the things I enjoy is going fast. Since I also don't like to spend lots of money, the best way to go fast cheaply is on a motorcycle. So, I ride. In my education on the topic, I've read Keith Code's books A Twist of the Wrist and A Twist of the Wrist 2.
As part of Keith's instruction, he introduces the concept of attention cost. The theory is we have a fixed amount of attention. Minor distractions reduce the amount we have to devote to important tasks. For example, as it relates to motorcycle riding, an air leak in your helmet will cause a tickle on your cheek, diverting attention away from the more critical shifting, braking, cornering and accelerating tasks. Fix the air leak and you will go faster around the track because you can pay more attention to the tasks that are important for speed.
I think this is directly applicable to photography and the question of whether to use auto mode or not. What is important to your shot? Where should you spend your limited attention?
My conclusion: automatic mode has its place. The key is to know how to use all modes of your camera, evaluate each situation you're shooting in to determine what's most important, and then choose the mode that's applicable.
1. To be clear, I have not talked with Bryan about this. I don't know his reasons. It's just his doing it that caused me to think about why one might do it in general.