6. Optical Weights

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 will feature footnotes at the bottom of the page which are traditionally set a couple of points smaller than the main body text. If there are extensive footnotes on each page, then the page will be uneven since the smaller font size will create a lighter grey at the bottom of the page.

A good text typeface will include four or five different variations of the font known as “optical weights”. Now this must not be confused with semibold or bold. This is a complete font within the typeface and typically each of the optical weights will have the option of italic, bold, semibold, bold italic etc.

Optical weights are designed to be set at different sizes so in our example above of the footnotes, we might set the footnotes in the small text weight of the font. Since the small text version is designed, as the name suggests, for smaller text, the font designer will have made the font sturdier at this smaller size so that the delicate serifs will not break. This is illustrated below where the serifs of the smaller weights are clearly heavier than that of larger weights (compare caption to display looking closely at the letter a).

Each typeface will typically have the recommended point sizes for each weight. Below is Arno Pro with five weights and the intended sizes for each optical font.

Although optical weights are designed to be used at the appropriate sizes, with subhead for headers etc., it’s not always the way they are used. For example, I have used Arno Pro Display Italic at 14 pt (way below the intended size of 21.5 pt and above) to create a dedication in a book. However, this must be used with care with the knowledge as to how this is going to be printed.

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.

Looking forward to your comments below!