Seeing rhythm, colour and texture

Most people learn to read a typeface one letter at a time — the bowl of the a, the terminal on the f. Useful for an exam. Almost useless in front of a real screen, where what you are actually judging is a paragraph you are looking at from two feet away.

This lesson swaps the microscope for a squint. Three properties do nearly all the work at that distance, and once you can see them you can diagnose a page in about four seconds.

Rhythm

The even alternation of stem and counter — black and white — as your eye runs along a line. Broken rhythm is what you are noticing when a paragraph feels "spotty" without your being able to say why. Common causes: a face with inconsistent sidebearings at small sizes, letter spacing applied to lowercase text, or a fallback font swapping in for two of the twenty-six characters.

Colour

Not hue — the overall grey value of a block of set text. Two paragraphs in the same size, weight and colour can have visibly different densities, and that difference is what makes one column of a two-column layout look heavier than its neighbour. Squint until the words stop resolving and compare the greys.

If you can still read it, you are not squinting hard enough. The point is to stop reading and start seeing.

Texture

The combination of the two, plus the shape of the paragraph's ragged edge. Texture is why a justified column and a ragged-right column of identical text feel like different documents, and why a measure of 110 characters feels exhausting before you have consciously noticed its width.

Try this now

Open any product you use daily. Blur your eyes until the text is unreadable. Where does the page go grey and even, and where does it clot? The clots are almost always where somebody set a heading and a paragraph in the same weight, or where a table has crept to eleven columns.