Sofie Beier Sofi

e Beierbis

ISBN 978-90-6369-271-1

designing for legibility

Reading Letters is a book about typeface legibility.

In our everyday life’s we constantly encounter a diversity of reading mat-ters, these being display types on traffic signage, printed text in novels, newspaper headlines, or ones own writing on a computer screen. All these conditions demand different considerations of the typefaces applied.

In a straightforward manner, the book discusses these aspects by drawing on typography history, designers’ ideas, and by reviewing available scientific data concerning the process of reading.

Easily accessible, and heavily illustrated, this is a most have for any designer looking for guidance when choosing a typeface for a given project.

Sofie Beier is a type designer, researcher and lecturer employed at the School of Design under

The Royal Danish Academy of Fine Arts. She holds a PhD from the Royal College of Art in London,

on the subject of typeface familiarity and its relation to legibility.

Reading Lettersdesigning for legibility

Copyright © 2011 Sofie Beier and BIS Publishers

Sofie BeierOvink

bis PublishersHet SieraadPostjesweg 11057 DT AmsterdamThe NetherlandsT (+) 31 (0)20 515 02 30F (+) 31 (0)20 515 02 39bis@bispublishers.nlwww.bispublishers.nl

ISBN 978-90-6369-271-1

All rights reserved.No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording or any information storage and retrieval system, without permission in writing from the copyright owners.

Reading Letters was partly funded by the Danish Centre for Design Research.

Text and designTypeface

Publisher

Reading LettersSOFIE BEIER

bis Publishers

designing for legibility

Introduction · · · · · · · · · · · · · · · · · · · · 7

1. Test methods · · · · · · · · · · · · · · · · · · 9

Readers’ preferences

Continuous reading

The search task

Visual accuracy threshold

2. Understanding reading · · · · · · · · · · · 21

Letter identification

Single letter and word superiority effects

Word wholes

Parts, wholes and context

3. Early approaches to legibility · · · · · · · 31

4. Theories on letter structure · · · · · · · · 37

Edward Johnston

Gerrit Noordzij

Frank E. Blokland

5. Stroke and contrast in history · · · · · · · 47

The Old Style stroke

The Romain du Roi

The Baskerville stroke

The Didone stroke

The Geometric stroke

6. The individual letter · · · · · · · · · · · · · 69

Internal letter relation

Scientific results

Designers’ ideas

7. Type for text sizes · · · · · · · · · · · · · · 85

Block text

Proportions

M-formula

Ink & printing

Type for screen

8. Type at a romandistance · · · · · · · · · · 105

Compensation for loss of detail

Proportions

9. The capitals · · · · · · · · · · · · · · · · · 113

Roman inscriptions

Relative width

Which is more legible?

10. Sans or serif? · · · · · · · · · · · · · · · 123

Ideas in favour of the serif

Scientific findings

Familiarity of the sans serif

11. Hanging and ranging figures · · · · · 131

12. The italic evolution · · · · · · · · · · · 137

The Cancelleresca italic

The development of the Didone italic

Cursive italic & sloped roman

13. Letter spacing · · · · · · · · · · · · · · · 149

14. Familiarity in history · · · · · · · · · · · 155

Reading and writing in the Middle Ages

Blackletter and Latin types

The Civilité type

John Baskerville and his peers

Didone and the French Revolution

15. The validation of legibility · · · · · · · 171

Index · · · · · · · · · · · · · · · · · · · · · · · · 178

Contents

AcknowledgmentParts of the book are based on my PhD thesis ‘Typeface Legibility: towards defining

familiarity’, written while affiliated with the Royal College of Art, London, UK.

Doing the development of the book, a number of people have kindly informed

me on various aspects of their own expertise. In this regard I would like espe-

cially to thank Dan Reynolds for his helpful feedback on the final draft and for

providing me with images of blackletter type. I would also like to thank Kevin

Larson and Mary Dyson for general advice on scientific legibility research. I am

very grateful for the input given by James Mosley enlightening me on historical

matters, and for the help provided by Jan Middendorp pointing me towards use-

ful typographical images.

Furthermore, I would like to thank Chris Burke for putting me in contact with the

Tschichold estate, Gerard Unger for providing drawings of Dwiggins’ puppet, and

Eric Kindel for the test material applied by The Graphic Information Research Unit.

Last but not least, a big thanks to all the designers and foundries who so kindly

have supplied me with images of their work. Without these, the book would

never have been the same.

Sofie Beier

IntroductionThis book will, on the one hand, help type designers create highly legible type-

faces and, on the other hand, help graphic designers determine the optimal

typeface for a given project.

Few of us will appreciate if the typeface we read is legible; however, we

quickly notice if it is not. Creating type for optimal legibility is therefore a

thankless task, since readers only register your failures. For instance, typefaces

presented under difficult reading conditions, such as small point sizes in low-

quality newspaper print or street and building signs viewed from afar, need to

be created in specific ways to function at their very best.

To understand the topic in depth, two very different areas of expertise

have been consulted. One area is that of punchcutters and designers who,

through their experience, possess useful knowledge that can help us better

understand the various aspects of the matter; the other is that of academic

reading research, where a significant amount of relevant scientific studies

have been carried out over the years.

Type designers have a subtle understanding for details and nuances that

seem difficult to test in a laboratory, but many of the theories and ideas

presented by designers do in fact lend themselves to laboratory testing.

Some theories have already been verified, while others have been rejected.

The outcome of this research has yet to be made widely available to design-

ers. Consequently, many designers make assumptions without really knowing

whether they are right or wrong. In a synergy between the two topics, this

book will evaluate typeface legibility from different angles in an effort

to provide useful information that can, hopefully, be transferred to practice.

7

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1Test methods

Scientific studies on legibility-related matters have been carried out in a

number of ways over the years. Many of the methods have been criticised

for being insufficient. An argument often raised is that we must understand

legibility fully before attempting to study it. One implication of this would be

that all existing test methods are ineffective, since reading is such a complex

process that no single method can ever produce sufficiently useful results.

A common criticism is that a reader who is placed in a laboratory setting

will always be aware of the action of reading, which means that obtaining

a realistic measurement becomes problematic. The claim is that the human

mind is too complicated for any valuable information to be extracted during

a laboratory test. Whenever one aspect is tested, a range of other factors will

inevitably influence the subject, and the experiment is bound to lead to inad-

equate findings. However, studies carried out in a natural environment allow

for too many uncontrollable variables, while a laboratory setting, on the other

hand, makes it easier to control and isolate the many correlating factors that

play a role in everyday life.

A central point of criticism that is voiced in the legibility debate is that

different test methods produce different results. Legibility researcher Miles A.

Tinker1 compared 10 typefaces in terms of visibility under reduced illumina-

tion, perceptibility at a distance, speed of reading, and the reader’s opinion

about the most legible type. In this study, he found little agreement between

the results of the four test methods. In the measurement of reduced illumi-

nation, bolder types performed better than lighter ones, a finding that had

much in common with the test of perceptibility at a distance. Tinker also

found that the reader’s opinion was less compatible with speed of reading

than the two other aspects, and that readers in general judged types that

10

perform well in distance studies to be best for comfortable reading. Instead

of viewing this as a setback for the prospects of scientific legibility investi-

gation, one might view the different findings as an indication of something

more useful. Comparisons such as these reveal that typeface legibility is not

a universal issue, where one feature or set of features improve legibility in all

reading conditions. In other words, the level of legibility for a given typeface is

not constant but varies, depending on the situation in which it is observed.

Figure 1.1. Different test methods pro-duce different results. The findings by Miles A. Tinker when he exposed the same typefaces to different test methods showed a large difference in performance1.The typefaces are illustrated with digital fonts that are similar in style to the metal types applied by Tinker.

Legibility ranking(1 = best performance)

Visibility un-der reduced illumination

Perceptibilityat a distance

Speed of reading

Readers’ opinion of legibility

Antique (illustrated with Bookman Old Style)1 3 3 2

Cheltenham 2 2 8 1

American Typewriter 3 1 9 6

Cloister Black 4 10 10 10

Bodoni 5 7 4-5 3

Garamond 6 6 1 5

Old Style (illustrated with Century Old Style) 7 4 4-5 4

Caslon Old Style (illustrated with Adobe Caslon Pro) 8 5 6 8

Kabel Light 9 9 7 9

Scotch Roman 10 8 2 7

11

Continuous reading Designers often argue that book typefaces should only be tested in running

text, as this is, after all, how the type is going to be read. The issue is not,

however, quite as straightforward as it may seem. Comparing two columns of

text set in different typefaces raises a range of potential dilemmas. Leading

and spacing in the text always interact with one another, an issue that is

particularly evident when matching two designs of different x-height (Fig. 1.2).

If the leading is kept constant, one of the two is likely to be at an advantage.

If, on the other hand, the leading is adjusted to give the typefaces a visual

similarity, one text might take up more space on the page than the other,

which may introduce a bias.

A common goal in studies of continuous reading is to measure reading

speed. It may, however, be problematic to assume automatically that fast

reading equals high legibility. Perhaps speed should not be the goal. Maybe

when we read a highly legible text, the type will make us read with less

effort rather than increasing the speed of reading. This notion is supported

by a study2 that compared text with different margins; the study found that

although the speed of reading was reduced when readers were exposed to the

text with larger margin, they had a better understanding of the content under

this condition.

Another central criticism in relation to tests of reading speed is the fre-

quent lack of significance in the measured time differences between the fonts

tested. Unfortunately, this does not necessarily mean that there is no differ-

ence; more likely, the test method simply is not sensitive enough to detect

any variation.

To test continuous reading, there are several methods to choose from. One

method is to look at oral reading. Here, the participant reads a text aloud, and

the researcher records the number of errors or the time it took. A problem

with this approach is that the situation is unnatural for most adults. It can

be difficult to determine whether mistakes are based on errors of identifica-

tion or errors of interpretation or memory. When reading aloud, we often use

similar words or restructure the text to improve the flow; this does not mean

that we actually decode the text that way. Another consideration is that oral

reading leads to a higher frequency of fixations on the line of text, and that

oral reading speed is about half that of silent reading3. Furthermore, because

the eye is faster than the voice when we read aloud, only substantial perfor-

mance differences will show up in the test results.

12

Figure 1.2. What leading can do to a text. Leading can post a challenge when comparing typefaces of different x-height. The optimal leading for a typeface with a small x-height is not always the same as the optimal leading value for one with a large x-height. Illustrated with the typefaces Brandon Grotesque by Hannes von Döhren, and DS Musee by Dino dos Santos, both set in 22 point size, with a line height of 22. Note the difference in the white areas.

Beautiful printing is an educator, the same as is any art. The thoughts of an author take on added value by reason of it. The mind is always receptive in proportion as it is helped to com-prehend the real mean-ing of the writer.

Beautiful print-ing is an educator, the same as is any art. The thoughts of an author take on added value by rea-son of it. The mind is always receptive in proportion as it is helped to compre-hend the real mean-ing of the writer.

Brandon Grotesque, 22/22 DS Musee, 22/22

13

Based on the problems related to measuring oral reading, it might make sense

to study silent reading instead. The challenge here is how to measure read-

ing when others cannot hear it. One way around this challenge is to test for

comprehension and check whether readers have understood the text that

they read. This does, however, lead to a new range of issues that need to

be addressed. How, for instance, can we ensure that participants all have

the same degree of interest in the topic of the text? If they find the topic

boring, will that influence their concentration, and will their comprehension

suffer as a result? Will we in fact be testing the participants’ intelligence or

simply their experience of being in a test situation? Furthermore, it has been

demonstrated that high-frequency words such as ‘the’ are read faster than

other three-letter words4, and that sentences in the active voice are recog-

nised faster than sentences in the passive voice5. If the experiment involves

comparing two different texts set in two different fonts, the level of high-fre-

quency words and the structure of the individual texts are likely to influence

the outcome of the study. Then again, if all participants are tested on all type

conditions, and if the test material is counterbalanced between conditions,

these issues should not cause problems.

Expert craftsmen magically produce a wonderful instrument, which reveals almost incredible improvement over everyday music producing machines.

14

The search task Another possible approach is to measure readers’ ability to locate specific

words or letters in a text. Such methods were applied in studies carried out

by the research unit working at the Royal College of Art6 in the 1960s and 70s.

Their reason for choosing this method was a dislike for testing the readers’

comprehension, as they judged the comprehension method as being influ-

enced by too many unaccountable variables that were not related to the

visual properties of the text.

The problem with the search task method, however, is that it is more

closely related to scanning than to actual reading. In addition, since most

reading situations do not allow us to know the exact words we are about to

read, the method is not a very close approximation of real-life situations.

When participants know what to look for, the interrelation between the

process of reading the word, and the processes of reading the individual let-

ter, is dominated more by the word process than is the case in more natural

reading situations (see more in Chapter 3). That being said, the search task

method is very useful for studying participants’ ability to identify a target

object located among other elements.

Figure 1.3. Eye tracking. The measure-ment of eye movements during continuous reading can provide researchers with useful information on lengths and durations of saccades and fixations. Illustrated with the typeface Stella, designed by Mário Feliciano.

15

Figure 1.4. Search task test material. Test material applied by The Graphic Information Research Unit working at The Royal College of Art in the 1960s and 70s. Participants were asked to locate the words on the left in the text shown on the right.

16

Visual accuracy threshold In this approach, the focus is on letter and word identification, while compre-

hension is not a priority. Participants in tests based purely on perception tend

to be unaffected by the awkwardness of the test situation. As we know, optom-

etrists can make rather accurate vision measurements in laboratory settings.

That is because word recognition occurs on an automatic level and is therefore

unaffected by the surroundings. This is confirmed by the famous phenomenon

discovered in 1935 by J. Ridley Stroop7. Asking participants to name the print

colour when presented with words such as ‘Yellow’ in a green colour and ‘Blue’

in a red colour, Stroop demonstrated that most participants found this to be

very difficult; thus, the study concluded that we recognise words even when it

would help us to ignore them (Fig. 1.5).

There are several methods for measuring visual accuracy; one way is to briefly

expose the participant to the stimulus. After this rapid exposure, which is so

short that the eye is unable to move from one fixation to another, the partici-

pant is asked to identify the presented material. Because of the single fixa-

tion, an obvious risk is that the test method might vary too much from a more

regular reading situation. On the other hand, it can be argued that the differ-

ence is not that significant, since the eyes are relatively stable when fixating

Figure 1.5. The Stroop effect. The task is to name the print colour of the word ‘Blue’ when it is printed in red, or the ink colour of the word ‘Yellow’ when printed in blue, etc. Illustrated with the typeface Ovink by Sofie Beier.

BLUEYELLOWREDGREEN

17

on a stimulus, both in short exposures and in normal reading situations. It

thus seems reasonable to assume that the perceptual processes would be the

same. Yet this may not always be the case. It appears that humans sometimes

process the same information differently, depending on the task they set out

to perform9. In the short-exposure method, the participant mentally prepares

for the task of perceiving the material in one fixation. In normal reading,

the fixation is a part of a larger process and is not treated as a specific task.

However, the method is useful for studying the legibility of individual charac-

ters or words and for identifying specific features for further investigation.

Figure 1.6. Testing short exposure with a mask8. To control the time frame in which the image will appear, it is helpful to let the stimuli be followed by some form of mask consisting of random dots or lines. That will remove the afterimage from the retina. a

a

18

Sofie Beier

Sofie Beier

bis

ISBN 978-90-6369-271-1

designing for legibility

Reading Letters is a book about typeface legibility.

In our everyday life’s we constantly encounter a diversity of reading mat-ters, these being display types on traffic signage, printed text in novels, newspaper headlines, or ones own writing on a computer screen. All these conditions demand different considerations of the typefaces applied.

In a straightforward manner, the book discusses these aspects by drawing on typography history, designers’ ideas, and by reviewing available scientific data concerning the process of reading.

Easily accessible, and heavily illustrated, this is a most have for any designer looking for guidance when choosing a typeface for a given project.

Sofie Beier is a type designer, researcher and lecturer employed at the School of Design under

The Royal Danish Academy of Fine Arts. She holds a PhD from the Royal College of Art in London,

on the subject of typeface familiarity and its relation to legibility.