If you are new to oil painting and want to start practicing, a good exercise to start with is a small en plein air painting. En plein air is French for "in the open air," and simply means that you paint outside rather than use a reference photo in your home. This type of painting can be difficult for beginners because you have to paint quickly to capture true hues before the light source changes. However, this is a great exercise to loosen up your stroke and to help you mix and match colors. Here are four tips to keep in mind when you go out for en plein air excursion:
1. Save Your Oils and Make them Count
Oil paints in general are much more expensive than acrylic-based paints. To get the most out of your oil paints, you should work with a mix of supplies. Before you go out painting, make sure you gesso your canvas. Gesso looks like white acrylic paint, but it's a little thinner. When it dries, it will prime your canvas and give it a good painting surface. Without gesso, the paint will seep into canvas grain, and you'll waste more paint trying to build up your colors. You'll want to gesso your canvases before you leave your house so that you are ready to paint when you go to a scenic area.
When you start painting, apply some base colors in acrylic paint. For instance, if you are painting a stream, apply a wash (diluted paint) of blue to cover the surface. Then on your top layers, you can add oil paints. If you are painting a larger surface, this step is really important. If you don't have basic colors already laid down, then you have to cake lots of oils for an opaque look—and again, you don't want to waste oils since they're expensive!
2. Focus on Colors not Details
An easy way for your painting to become cluttered is to get bogged down in details and realistic depictions. With en plein air, you really want to practice mixing colors on your palette that accurately match what you see. A good way to correct yourself from putting in details is to squint when you look at your composition. Although squinting will make your eyesight blurry, it will give you a better sense of shape, light/dark values, and hues.
3. Bring an Easy-to-Carry Pack
This may seem like an arbitrary step, but en plein air is surprisingly a workout! You have to lug around oils, brushes, canvas, and possibly an easel. You may spend a good amount of time walking around, looking for a perfect composition and a bit of privacy. Make it a little easier and pack your essentials in a backpack. Make sure you bring a fold-up chair and bag so that you don't have to stand for long periods, and make sure you bring a hat for shade and a water bottle and snack for breaks.
4. Know Your Warm and Cool Colors
While everyone learns how to mix primary and secondary colors in preschool, it can be surprisingly difficult to mix tertiary and subtle variations between those colors. When you mix colors, focus on warm values and cool values. While you may have been taught that cool colors are strictly blue, green, and purple and warm colors are strictly red, orange, and yellow, all colors actually have warm and cool variations. For instance, "Cadmium Red" is a warm red color but "Alizarin Crimson" is actually a cool red. This may seem confusing at first, but with practice you'll start seeing warm and cool variations in colors. In your composition, try to balance your warm/cool tones with a 70/30 ratio. This will give your piece more interest than an even split.
Whether you have dreams of showcasing your work with a company like Silverman Gallery, or you simply paint for pleasure, if you follow these tips and study other works of art, you'll be well on your way in creating original oil paintings in an en plein air style!