6. Optical Sizes

This is the sixth of a 10-part series of the Ten Keys to Seamless Typesetting.

We have talked extensively about typographical details such as true small caps and superiors in order to keep the colour of the page even.

Many books have footnotes set a couple of points smaller than the main text. Depending on the typeface and printing conditions, extensive footnotes can appear lighter than the body text. An appropriate optical size can help keep the colour of the page even.

A type family may offer several optical sizes: versions drawn for different ranges of point sizes. These are distinct from weights such as regular, semibold and bold. Each optical size may itself be available in several weights and in roman and italic.

Optical sizes are designed for different uses, so in our footnote example we might choose a small-text or caption cut. Its sturdier strokes and serifs help it remain clear at a small size. The illustration below shows how the serifs change between caption and display designs; compare the letter a.

Each optical size usually has a recommended range of point sizes. Below is Arno Pro with its five optical sizes and their intended ranges.

Although optical sizes are designed for particular ranges, with Subhead intended for headings, the intended size is not the only consideration. For example, I have used Arno Pro Display Italic at 14 pt, below its recommended range, for a dedication. Such choices need care and should be checked at the final size with the printing method in mind.

If you have a manuscript that you wish to be typeset seamlessly with footnotes that are not too light, then contact us for a no-obligation discussion by clicking here.

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