A portrait painting is a unique image of the subject. When you set out to do a portrait you have to have some sort of a method. Mostly the process is about the fall of light, the tonal structure, which serves as the foundation on which you expand and develop your own interpretation and artistic handling. At the very least you hope to achieve a likeness; at best also to portray a sense of the character that sits before you.

Materials for the job

The canvas size for a life-size head-and-shoulder can be a 19¾x15¾in (50x40cm); I generally go for 23¾x19¾in (60x50cm) canvas. Primed linen is the best. I use an earth palette of Old Holland or Michael Harding oils: titanium white (you can use a warm white alternative), yellow ochre, light red, Chinese red (or cadmium red light for a much cheaper alternative), Venetian red and ivory black. A tip to remember is to keep Venetian red colour mixes to shadow sides and light red colour mixes to the light or bright side of the face. The cadmium red can go anywhere in the light or dark values. Useful optional extra colours are raw umber, burnt umber, raw ochre.

Brushes: flats, rounds and mostly filberts in both hog hair and sable. Useful sable filbert sizes are: 6, 8, 9, 10. A couple of flats are good for sharper edges and planes of cloth folds. Hoghair brushes are great for dragging the paint around and to scumble in backgrounds (size 22, 24) and to get a smoky effect, especially when mixed with a painting medium. You will also need a small round sable such as a 1 or a double 00, which is used especially for the tiny pin-pricks in the highlights of the eyes.

Painting mediums are great to use with oils; use turpentine or try mixing one-third turpentine, one-third linseed stand oil and one-third Canadian balsam. Michael Harding’s Oleo resin is very good. You can add a little linseed oil to this if desired to make it more silky – it’s good for blending and softening edges where one colour meets another. White spirit dulls colours so use it for cleaning, or leave your brushes in a flat dish of vegetable oil to save washing each time. The other well-known rule is to paint fat over lean, so more turpentine in the beginning and you can incrementally add more medium as your painting progresses. The portrait here was painted over several sittings with drying time in between.

It’s good to have a specific directional light source as it makes your job easier than having a flat light with no shadow patterns. It provides a shadow side to a nose and corresponding shadow side of the face. If you don’t have a north-facing studio a good-quality LED natural light is best. If you are standing to paint, raise your sitter on a platform; the idea is to have the same eye level as your sitter. If they are a little higher than your eye level it will add an aristocratic air – but not too high. Sometimes it’s good to have a sitter lower than you, for a portrait of a child, for instance.

Values

Begin by toning your canvas with a mix of black and yellow ochre, adding turpentine to make it a little more washy. Do not put white into the mix, as subsequent painting applications will sink and go chalky. Brush your semiliquid mix over the whole canvas with a big hog-hair brush and softly wipe back with a clean rag. The result should give you a transparent tone as the white of the primed canvas still comes through. You can use other colours to make a ground, just remember not to add white. Leave the canvas to dry, preferably overnight, so that you don’t keep lifting the tinted ground when you paint.

If you made a preliminary sketch, dab back your charcoal drawing with a cloth so that your paint does not slide around and go a dusty grey. Or draw straight away in paint. Mix a dark shade like brown with cadmium red and ivory black; make it thin and transparent as shadows always read better like this. Make it warmer or colder by varying the amounts of each colour, or use your the correct value than the colour.

Start painting at the shadow side of the nose (roughly halfway down the canvas; if you are on a three-quarter head pose remember to place it more to one side so you don’t run out of canvas for the rest of the head) then lead onto the shadow side and paint the eyebrow. Refrain from detail. A size 5 or 6 hog-hair or sable filbert is good. Look at the angles the eyebrow is making – you are drawing with paint. The nose-to-eyebrow relationship you make establishes the proportion to the rest of the face. Look at the space between the sitter’s eyebrows and sketch in the other eyebrow. You can then map out the cheekbone on the shadow side, and under the jaw.

Use bigger hog-hair brushes for the background and shadow side of the face. Keep your shadows as transparent as you can, adding a little medium/turps to thin and drag. It’s a general rule to establish dark values over which your medium and light values will be built. Get the head on a neck and shoulders early on, even if you don’t paint them in for a while.

Your mid-tone is a mixture of red, yellow ochre and white; you can add a little grey (ivory black plus white) to knock back the brightness or a little raw umber. Ivory black and yellow ochre make a range of greens from warm to cool; adjust by adding a little white. You can adjust again with light red for the light side of the face or Venetian red for the shadow side of face. Are the values good? Are the shapes as correct as you can make them? Are the colours cool or warm?

Details

When shaping the head you need to be able to correct it, so the background value becomes as important as the head shape. I use a big hog-hair for the background colour. Again, keep your colours thin and transparent as you are merely painting the first stage of the portrait, the lay-in. If you get white or greys in the dark background they will become quite chalky and sink when drying. Mediums and retouch varnish solve this problem in subsequent painting sessions, though.

You can achieve a likeness just with shape and values and not much detail. Rather than drawing eyes, go for sockets and apply a dark value to situate the iris of both eyes. A small filbert or round is used for the pupils in ivory black, and a 00 brush for the tiny pinprick of highlight using white only. If misplaced, dab off with a finger and reapply.

If you can’t see detail when observing from life, don’t paint it. When correcting, try dragging the paint around with whatever brush you have assigned for that role. Often you don’t need to reload brushes, but drag directionally to change a shape subtly. A clean fan brush or any soft flat brush can be used to blend one colour lightly into another, which also softens all your edges and makes a good ground for the next session. It is a good idea to do this at the end of your first sitting as it slightly blurs the image and makes your job easier for the next session, especially if some shapes are not quite right. It also makes your image become more three-dimensional.

DEMONSTRATION Simon Tyszko

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