Why do I like plein-air painting? It is the street-fighting of painting.
To explain what I mean by this I'm going to exaggerate things a bit. This post is tongue-in-cheek to just make my point.
It's very comfortable to sit in the studio, and take your time with a painting. One of the prime benefits of working with oil paints, is you can keep working on the same oil painting almost indefinitely and forever. In the near term, the paints take hours or days to dry, allowing you to make adjustments or just scrape off what you just did. In the long term, you can always just paint over something you don't like. (Don't ask me if I've ever scraped dried paint off a painting.)
With Plein-Air painting, you have one job. You have a limited amount of time, and your job is to try to capture something with oil paint, that resembles the spot that you decided to set up and paint. The light outside is constantly changing. The sun never stops moving. As the sun moves, shadows move. The sun laughs at you in the golden hours, the points at which it is close to the horizon. The closer the sun gets to the horizon, the more rich and awesome the colors, and the shorter the amount of time the visual spectacle of those colors, enveloping the landscape, will last.
In the studio, you can control everything. You control the light, the temperature, the subject matter. You can paint from photos. However, painters who observe nature eventually realize this is like going to a glorious Las Vegas buffet, but you can only eat with a toothpick. If you go outside, and take your time to really look at the world, there is so much to take in, and so much more than a camera can capture.
When you are painting outside, you are flooded with information. You have to make decisions quickly. You have to quickly decided where you want to set up. You have to quickly decide what part of the landscape you want to paint, keeping in mind what you can paint. You have to set up quickly, squeeze out and mix up your paints quickly, and start your painting process without messing around.
Once you get going, you have to quickly decide how you are going to capture what you see. You can't paint everything, and you can't paint every leaf on every tree (let alone any leaves) This means you have to essentialize. You have to mentally focus on the few key elements that will create an impression of what you are observing. Once you begin, you have to move quickly. Every painting has a foreground, middle-ground, and background, which you need to establish. The painting process always has a beginning, middle, and end. You need to know how to move through and be aware of your time.
So this is why I call it the street-fighting of painting. It's a test of your skills and what you know. The compressed amount of time means you really need to already-know, and have internalized the principles of painting that create a successful impression. There is no time to test things out or try and figure things out in the middle of your painting session.
Physical street fighting may be deadly. I don't encourage it. Painting outdoors can be painful and maybe deadly to your ego. You may think you are hot stuff in the studio. But when it comes time to really throw down, can you really hang in there and take on nature on its own terms?
I am not going to pretend by any means that I've mastered this...not even close. I do know that it provides a guiding light for everything I study. I do know it provides a way to put to the test all the theories, principles, and heuristics one I read about and learn about when it comes to painting.
I have so many canvases and boards that I've taken outdoors for painting, only to fail miserably and not have anything to show for the time and effort. Most of the time I try and think about and observe what went well and what did not.
But there are a few times when everything has come together and I really feel like I at least got something down. Those few times when it all works, makes all of it worth it.