When it comes to drawing facial features, the eyes can be challenging because, well, realistically capturing “the windows to the soul” is no easy task. And while you probably learned a simple formula when you were a child — draw a football with two circles inside for the iris and pupil — no eye actually looks like that.
Which is why the most important thing to remember is to draw what you see, not what you know. Every person’s eye is different and no visual formula can replace the real thing. That said, there are a few tips you can follow no matter whose eye you’re drawing.
1. An Eye Is Asymmetrical
Rather than tapering smoothly to a point on either end, an eye has subtle differences in the shapes of the top and bottom eyelids.
Take note of the photo above. The top eyelid is flatter along much of its length than the bottom, except where it curves downward to meet the tear duct on the left. The bottom lid is curved along most of its length, with the most pronounced part being where it sweeps up to meet the top eyelid on the right.
2. The Human Eye Is Three-Dimensional
Your eyeball is a sphere, but most of it is concealed by your eyelid. When drawing, the eyelid should look as though it’s wrapping around that spherical shape. This is most obvious in a profile view.
3. The Iris Is Almost Never Completely Visible
Unless the person you’re drawing is very surprised, most of the time the iris will be partially covered by the top eyelid. In some cases, both the top and bottom eyelids will cover the iris, like if your subject is sleepy or squinting.
4. The Top Eyelid Casts a Shadow
Because the top lid projects out a little further than the eyeball itself — and because it has the thicker set of eyelashes — the lid casts a shadow along the top of the eyeball in most lighting situations. This can be easily depicted by making the line of the top eyelid thicker than the bottom.
5. The Top Eyelid Receives More Light
The best way to draw a realistic eye is to use value to suggest volume.
Assuming an overhead light source, the underside of the brow overhangs the eye and is therefore in shadow. The upper eyelid faces upward, so it receives light and also casts a shadow on the uppermost portion of the eyeball. The eyeball itself is curved, so the bottom receives less light. And because the bottom eyelid faces down and receives little light, it also casts a shadow on the portion of the face directly beneath it.
It’s important to remember that every eye is different. Thinking about how value suggests three-dimensionality can help you go a long way in drawing realistic eyes.