The underdrawing in charcoal on canvas, woman in a tropical pool.
The underdrawing in charcoal on canvas.

Painting the Traditional Way

– Part 2 –

The Underdrawing


After sizing, priming and toning the canvas, it was time to begin the underdrawing. 

What is an underdrawing in oil painting?

An underdrawing is basically a charcoal or chalk drawing done on the toned canvas in preparation for oil painting. Charcoal is easy to wipe off, which makes it suitable for working out mistakes in the drawing before progressing to the painting stage.

I was commissioned to create an oil painting of a woman bathing in a tropical mountain pool with a waterfall and lush green foliage contributing to the peaceful ambience. The painting is heading for Australia to a natural health clinic, so I wanted to depict something beautiful, peaceful, magical and the idea of being close to nature – a beautiful woman in a refreshing mountain pool.

Step 1: Starting with a charcoal underdrawing

Charcoal rough sketch of woman in tropical pool
Starting off with a rough charcoal sketch from life on paper.


I started off with a preliminary drawing on a large sheet of paper using my girlfriend Janine’s back as a quick reference. She doesn’t enjoy posing very long, so I had to hurry and do a quick vine charcoal gesture drawing from life.

It isn’t really the most accurate drawing I could have done, but it was just to give me a basic idea of the pose. I’m planning on using photographs as little as possible in this painting. I asked her to imagine herself wading hip-deep into cool mountain water, thereby gaining a natural pose instead of something too superficial or unnecessarily dramatic.


Step 2: Transferring the drawing onto canvas and creating the underdrawing

The underdrawing in charcoal on canvas, woman in a tropical pool.
The underdrawing in charcoal on canvas.


Now that I had a basic idea of the proportions and a concept for how I want to compose the painting and how to place the parts, I copied the underdrawing free hand onto the canvas with vine charcoal and black chalk.

This is where I was glad the pink ground was strong enough to withstand the constant rubbing out and reworking of the charcoal drawing on the canvas. It took a while before I was happy with it.

Detail of the charcoal underdrawing of the left hand
Detail of the charcoal underdrawing of the left hand.

The Red Lories

Red Lories charcoal underdrawing
I drew a pair of Red Lories in charcoal, adding to the tropical feel of the painting.


I added a pair of Red Lory Parakeets as I want to enhance the composition with these beautiful bright red birds. They also add to the tropical ‘feel’ of the painting.

I drew them from my imagination, although I used several reference photos to understand their basic build, shape and length of the tail, their colours etc.

Red Lories are native to the rain forests of Australia, and so I found a bird species that is geographically correct – seeing that the painting is heading for Australia.

The room that the painting will be hanging in has lilac-coloured walls. That is another reason why I chose a pink ground. The bright red of the birds were also chosen as part of my colour-scheme so that the painting looks really good in it’s new home. Planning your colours beforehand is important, but I’ll talk about it as I go through the steps.


A home-made charcoal drawing stick

I made this charcoal drawing stick to help me to get a better view while standing back as I was drawing. It’s basically an old paint brush with the hairs pulled out and the metal ferrule wrapped around the piece of chalk, conte or charcoal.

Standing back, especially when painting or drawing on a fairly large canvas, is very important. It’s easy to get ‘tunnel vision’ when drawing too close up. Another way to check your anatomy and composition is to check your artwork every 20 minutes in the mirror.

This will show up any glaring proportion issues that you may miss. Your brain compensates and adjusts the way you see things when you’ve been working on a drawing for too long. It’s important to have a fresh eye.

Homemade charcoal drawing stick from old paintbrush handle
My homemade charcoal drawing stick from an old paintbrush handle.


Brushing off the excess charcoal

Once I was happy with the charcoal sketch on the canvas, I took a dry rag and wiped it over the drawing to remove the excess chalk and charcoal. I then dipped the corner of the rag in a little bit of gum turpentine to wipe away the mistakes and clean up the lines. I had to be careful not to rub too hard with the turps-soaked rag as I didn’t want to damage the pink ground layer with solvent.

This creates a ghost-like image for the imprimatura to come.

The excess charcoal wiped off the underdrawing
The excess charcoal wiped off the underdrawing.


Step 3: Painting the imprimatura or first underpainting layer

Painting the imprimatura with burnt sienna.
Painting the imprimatura with burnt sienna.


What is the imprimatura?

Imprimatura means the ‘first paint layer’ in Italian. Basically I went over the lines of the charcoal drawing with thinned-down paint to ‘seal’ the drawing.

You can also do an imprimatura by drawing on a white canvas or board, then washing a transparent layer of colour over the drawing.

I mixed a bit of burnt sienna, and a touch of a lean medium of linseed oil and white spirit on my palette. Then I painted over all the charcoal lines, refining the drawing with the oil paint. The black of the charcoal mixes a bit with the burnt sienna. I quite like this effect and the smoky brown/orange colour.

Traditionally, some artists  would go over their charcoal drawing with a fine brush and ink. But I go straight for it with a thin line of oil paint and a round hog’s hair or sable brush, depending on how detailed the drawing is.

Keeping the paint thin allows you to build up values – light and dark – to create shading. The light travels through these thin layers reflecting the paint as a transparent glossiness. Like a kind of glazing technique.


The imprimatura of woman in a tropical pool
The imprimatura of Woman in a Tropical Pool.


The sienna dries fast, especially mixed with a little medium and solvent. I blend the colour into the canvas with a natural hog’s hair filbert brush, and the effect is a transparent orangey shading. The thin underpainting dries quickly.

I can start with the next layer in a day or two.  You can use any fast drying pigment like burnt or raw umber, siennas, ivory black, ochres, or red earth. The idea is to have a fast drying, lean, first oil layer.


Using solvents in the preliminary underpainting

Be careful with being too liberal using solvents on a painting. I usually prefer to use the paints as they come from the tube as much as possible, or mixing my own mediums as needed, according to the purpose.

Besides solvents being highly toxic and having a strong smell (odour-less mineral spirits might not smell, but you’re still breathing in toxic fumes), too much solvent can dilute the binder in the pigment, weakening the bond to the surface to the point that they cause the paint to flake or powder off.

Using a little bit of solvent in the beginning stage is OK because solvents dry by evaporation. (Oils like linseed, walnut, etc, dry by oxidation). You also want to keep the first layer fairly lean. Mixing a little solvent helps with the underpainting as it gives the paint has a nice flow over the drawing and helps it to dry quickly.

I would advise not mixing so much solvent that the paint begins to drip and run off the canvas.

It’s important to remember the ‘Fat over Lean’ Rule here, namely because having an oily layer drying through oxidation in the bottom layers of your painting may cause cracking issues later on, as those oils start drying beneath thinner, more brittle layers above them. Fat over lean may be better understood as ‘flexible over less flexible’.

This is why I generally keep my painting layers fairly thin naturally. Neither over-thinning with solvents, nor making them too fatty with oils. (Near the last stages of my painting I usually start adding a more fatty medium for final glazes etc).

In the next post, I’ll start refining the anatomy and adding the ‘Dead Layer’ and the middle colours.


Check out my figure paintings here.


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