The mouth has complex, soft forms, and is capable of a wide variety of expressions. The lips vary from person to person, with there being a lot of individuality, but also common patterns. However, this isn't the limit of the mouth; the muscular forms that operate the mouth change the surface of the surrounding face, creating complex forms and creases.
Placement of the Mouth
In previous lessons, we have divided the face into thirds from the hairline, using the eyebrows and base of the nose as markers. The structures of the mouth sit in the bottom third of the face.
(Facial proportions in front and profile views)
After breaking the face into thirds, the distance between the nose and the chin has been further split into thirds. The mouth sits on the top third, on the centreline of the face below the filtrum – the dip in the centre above the upper lip. Generally, the chin sits within the bottom third. It is tricky to use proportion for the lips, as the size of the lips varies significantly.
The width of the mouth can be quite variable too, but typically the corners of the mouth sit within the middle of the eyes by a bit. It is useful to make a vertical comparison the corners of the mouth with the edge of the iris, but they tend not to line up perfectly. The eye may also be looking in a different direction, or the mouth in a different pose.
(Comparing angles to the vertical helps with placing the mouth in profile)
In profile views, the third divisions still work, though there is a lot of variation in the angle of the front of the face. It is useful to vertically compare the lips to the brow line, but they tend not to line up – this angle can vary from near-vertical to quite pronounced, and is useful for capturing likeness. You will also find that there is an angle between the upper and lower lip, created as the upper lip tends to protrude a little further out.
Structure of the Mouth
Whilst we often think of the mouth as the lips, there is a complex of muscles that operates it, and underneath that, the round form of the teeth. This gives a lot more bulk to this part of the face, meaning that the lips sit on a rounded plane.
(The lips supported by the teeth and muscles of the mouth)
The lips are somewhat protruding from the flat plane of the face due to this mass of the jaw and muscles underneath.
(Try to imagine a round form behind the lips, that they wrap to – this helps capture the curvature of the mouth)
Because of the roundness of these forms, the mouth and lips curve to fit them. This is less apparent in a frontal view, but is important to recognise in three quarter and tilted angles. The lips can be tricky, but like the other features of the face, they have common structure that is then distorted into different shapes for different likenesses.
To start, I tend to find the line of the mouth, as this helps with proportion early on in the drawing, and we can build around it. This part of the mouth forms a flattened 'M' shape, with a slight curl at the ends for the corners of the mouth. For the upper lip, I use another 'M' shape, and a rounded 'W' shape for the lower lip. It is important to pay attention to the shapes of the upper and lower lip, as they are distinctive. The lower lip tends to be more rounded, and softer than the upper lip.
The lips can be split into five sections, three for the upper lip and two for the lower lip. The centre 'V' shape lines up with the filtrum. The two triangular shapes next to it are flatter than the two rounded forwards making up the lower lip. Sometimes these are pressed together to almost seem like a single form, but you can often see a slight crease at the centre.
Keep these forms in mind as you draw the lips, especially in three-quarter views, as they will create subtle overlaps.
Putting It Together: Drawing the Mouth
The two big challenges of drawing the mouth are form and edge. The forms are subtle, and lead to gentle tonal transitions. In turn this means we need to be careful about the types of edge we use. There are no hard, sharp surfaces to make hard edges here – often these come from cast shadows from the upper lip or nose.
(Different kinds of edges in lip drawings. Artists (Top to bottom): Jean-Baptiste Greuze, Stanley Spencer)
As a quick reminder, there are four main types of edge – hard, firm, soft and lost – which vary from being a crisp, immediate transitions from one tone to another in a hard edge, to a graduation of tone in a lost edge. Lips tend to be mostly comprised of soft edges, with lost edges indicating form transitions and a few firm edges giving definition, and perhaps the line of the mouth.
Try to err in favour of soft edges – often working a bit softer than the reference will look more naturalistic, and represent surface qualities better. These is no definite edge between the lips and the face. There are more firm parts, as we see along the upper lip and centre of the lower lip, but the edges on the sides of the lips tend to blend in with surrounding skin.
(Rhythm of forms around the mouth)
The forms around the mouth are sympathetic to the lips as well. Above the upper lip they curve around to the corners of the mouth, whilst the grouping of muscle attachments to the corners of the mouth create a little bulge. Under the lower lip, there is a dip before the chin protrudes out to cushion the jaw. This creates an 'H' shapes depression that curls under the lip.
Over to You
Like all the other features, I am going to recommend drawing lots of quick studies of lips and the mouth. Try to capture lots of angles, but in particular, try to draw from lots of different faces.
(Studies of different lips)