Measuring Proportions with a Pencil

A pencil held at arm's length is a measuring instrument. It will not draw for you. It will tell you how many times one part fits into another, which is the question memory gets wrong. The method is old, plain and easy to cheat. The cheat is moving your arm, or measuring once and then ignoring the answer because the drawing already looks nice.

One distance, one eye

Sit or stand where you can stay. Stretch the arm fully and lock the elbow. If the arm bends halfway through, every measurement changes scale and the numbers will not agree. Close one eye. Two eyes give you two slightly different views, and the pencil will seem to jump.

Line the tip of the pencil up with one end of a unit you can see clearly: the width of a cup, the height of a head, the length of a book. Slide your thumb to the other end. That gap on the pencil is one unit. Drawing Aids, from the Grid to the Prism puts this stick in a longer history of tools. It is the one you already own.

Compare parts, do not collect numbers

Turn the pencil, still at arm's length, and see how many of those units fit into another length. A cup may be as tall as it is wide, or nearer one and a half widths. A head in a portrait may fit into the body a certain number of times. You are after a comparison, not a millimetre.

Mark the comparison on the page lightly before the drawing hardens. If the page says the cup is twice as tall as it is wide, and the pencil says otherwise, believe the pencil and change the page. Drawing Hands from Life in Short Sittings improves quickly when the palm is measured against a finger instead of drawn from the word hand.

Where the method goes wrong

Leaning forward to see a detail, then measuring from the new seat, mixes two scales. Decide the view and keep it. Measuring a photograph on a screen and a cup on the table with the same enthusiasm also mixes worlds. Measure the thing you are drawing, from the place you are drawing it.

Another fault is measuring everything and never looking at the whole. Take three comparisons, not thirty: the largest width against the largest height, one internal part against that unit, and the place where the centre of the subject falls. Then draw. Check once more at the end. A drawing that is only a pile of correct fragments can still have a crooked axis.

From the stick to the page

The pencil gives a ratio. You choose how large the drawing is. If one unit on the pencil will equal two centimetres on the page, keep that decision. Do not enlarge the interesting part and shrink the dull part. That is how a handle becomes too big and the cup too small, each of them carefully measured against a different secret scale.

Value First: Why a Grey Study Saves the Painting is the tonal partner. Proportion places the shape. Value tells you whether the shape reads. A well-measured outline with no contrast can still disappear. Measure first, then design the darks. Do not hide a proportion error inside a pretty shadow.

Frequently asked questions

Which end of the pencil do I use? Either, as long as the tip and the thumb mark a clear gap you can repeat. A long pencil is easier than a stub. The brand is irrelevant.

Do I measure every time? Measure when the subject is unfamiliar or when a drawing looks wrong and you cannot say why. A ten-minute gesture can skip the stick. A careful study of a jug should not.

Why do seated and standing views differ? Because your eye level changed. Both can be correct. They are not the same picture. Mark which one you measured, and do not combine them.