Artsy Crafty Library: How to make an oil underpainting

I was intimated by all the rules when I first started working with oil paints. One of the processes that helped me sort it all out was underpainting - the first layer of paint on the canvas.  

What is underpainting?

Let’s say you’re ready to start a new painting. It is a great feeling to jump into a new project! But now you have a big, empty canvas and must figure out where to start.

This is where the underpainting process helps! Underpainting creates a foundation from which paintings are built and incorporates several of the more confusing oil painting rules.  

How do I make an underpainting?

Start by taking a small amount of paint and mixing it with paint thinner. In the photo, you can see how paint thinner changes the texture of the paint. 

Dip your clean brush into your paint thinner to the mid-point of the bristles and then mix it with your paint. You want to shift the pigment so that it moves like a liquid but is not so diluted that it drips down the canvas. Take the thinned paint and cover the canvas in an even layer. 

Laying out the image

Once you have the canvas covered in the underpainting color, you can start laying out your image. Wipe away places where you need a lighter color; you can add a little bit more paint to areas that should be darker.

In this stage, you can play with the size, positioning and composition of your painting. Did you place something but don’t like how it turned out? Just wipe out that part and try again! This gives you a trial period to make sure everything you want to go into the painting has a place. You’ll know you’ve finished your underpainting when you have an outline of your piece on the canvas. 

What color do I use?

One last thing about underpainting: you can use any color. Many beginners will use Burnt Umber or Burnt Sienna (both brown colors) for underpaintings.

As you get more comfortable with the process, pick a color that contrasts with the final colors of your painting. In the sample I made, I picked a color called Alizarin Crimson, a pink color that will work well with dark tones of the nighttime scene I am painting. 

Check out these books to learn more about getting started with oil painting.