Values with hatching: the five tones

A pencil sketch doesn't live on beautiful lines alone. What makes a building look three-dimensional is the difference between light and dark: the sunlit façade against the shadow side, the deep hole of a window against the bright wall. That's exactly what this lesson is about. You'll learn to reduce your tones to a handful of clear steps and to hatch them so that the shape of each surface reads without you having to explain it.

Five tones, not fifty

Work with a scale of five steps. Step one is untouched paper white – not "very lightly dabbed", but genuinely empty. Step two is a delicate light grey, which you can achieve with an HB and little pressure, or with a 2B and a very light hand. Step three is a mid grey, in which the individual strokes may still be visible. Step four is a rich dark grey, usually with a 4B. Step five is the deepest black your pencil can produce, typically a 6B with pressure.

Set up this scale once at the back of your sketchbook: five patches of two centimetres each, side by side, from white to black. Then hold the page at arm's length. If you can't clearly distinguish the steps at that distance, they're too close together – in that case, make the dark ones darker. It's exactly this test that later decides whether a sketch has impact or sinks into a uniform grey.

Four ways to hatch

Parallel hatching is your basic technique: even strokes in one direction, with similar spacing. You control the tone through density and pressure, not by scribbling over it. Place each stroke deliberately and lift the pencil at the end instead of scrubbing back and forth – that keeps the edges of the area clean.

Cross-hatching lays a second layer on top, slightly rotated. An angle of about thirty to forty-five degrees works well; exactly perpendicular quickly looks like a fly screen. Each new layer takes you roughly one value step deeper, which is a very controllable way downwards.

Directional hatching follows the form: on a pipe, a barrel or a column, the strokes curve with the roundness, and the object becomes round before you even have any tone. And finally, flat tone with the side of the lead: you tilt a soft pencil almost flat onto the paper and pull large, even patches with the broad side of the lead. It's quick, keeps the area calm, and is ideal for roofs, streets or large shadowed walls.

Direction tells you the plane

Hatching isn't just tone, it's also information. Vertical strokes on a façade say: this surface stands upright. Horizontal strokes on the ground say: this surface lies flat. On a street you can also tilt the hatching slightly towards the vanishing point, which reinforces the perspective. Sloping roofs get strokes that follow the pitch of the roof.

What matters is consistency: within one surface, the direction stays the same. If you switch from vertical to diagonal halfway up a wall, the surface visually tips and the eye stumbles. If you keep the direction consistent per plane, people will read the volume of a house even when the outlines are missing.

Squint, then lay in the shapes

Before you hatch, squint. If you almost close your eyes, details disappear and the scene breaks down into a few large areas of brightness. That's exactly the information you need.

Then lay in the shadow as one connected shape, in a single tone. Often the shadow side of a wall and its cast shadow on the ground belong together and form a single figure – draw them as one, too. Only once that shape is in place do you go into it and create differences: a little darker right where it meets the ground, a little lighter where light reflects in from the opposite wall. The most common beginner's mistake is the reverse approach: shading every detail separately. That produces a patchwork with no clear light.

The deepest black is in short supply

Step five is precious. Use it in only a few places, where there's space behind an opening: in window cavities, under archways and canopies, in passageways, in the gap under a car. If you put this black next to an area of paper white, the sketch sparkles. If you spread it over half your surfaces, it's just dark.

Edges stay edges

Resist the urge to smudge with your finger, a cloth or a blending stump. That gives mushy grey, flattens the paper grain and takes the light out of the picture. You create tonal transitions through the density of your strokes, not through friction. There is one exception: if you deliberately want fog, rain, smoke or great distance, an edge may be soft – but then as a decision, not as a repair, and preferably with hatching that fades out and grows ever looser, rather than with your thumb.

Exercise

Find a corner of a building outside or from your window where the sun clearly comes from the left, so that one façade is bright and the other is in shadow. Spend five minutes drawing only the outlines, thin and without tone.

Then you have five minutes for exactly three tones: paper white for the sunlit left surface, a mid grey in parallel hatching for the shadowed right surface, and the deepest black exclusively in the window openings and under the canopy. Nothing in between.

In the next five minutes, expand to five tones: a light grey for the ground or the sky, a dark grey for the cast shadow on the ground, hatched horizontally. The last five minutes are for checking: hold the page at arm's length and squint. Can you distinguish all the steps? Is the white still white? Don't smudge – just add more hatching wherever a tone looks too weak to you.