Abstract:
Studies in the field of legibility research date back more than one hundred and
ninety years. Typographers, psychologists, oculists, physiologists and educators
are amongst those. who have done research and have written about legibility and
related fields of reading research. These researchers provided valuable
information about factors of legibility. As early as 1878, Professor Javal of the
University of Paris established that a reader's eyes move along a line of print in a
series of quick jerks (Spencer 1969:13). This was contrary to the popular belief
that a reader's eyes move along a line of print in a smooth sweep. Javal called
these quick jerks saccadic movements.
Apart from eye movements, other factors viz. illumination, colour, heart rate, blink
rate, visual fatigue and typographical factors were investigated. It is especially
legibility studies involving typographical factors that are of interest to the designer
and typographer. Research has provided guidelines concerning the legibility of
telephone directories, newspaper headlines, backbone titles, line spacing, the
length of a line of type and electronic text, to name but a few.
Graphic design is a discipline that is intrinsically linked to art, commerce and
communication. It can cover everything fiom a simple image that conveys a
single phonetic sound to a major component in a public relations programme or
advertising campaign. In its simplest form the function of graphic design is to
persuade, inform and to identify (Hurlburt 1981 :22). Different techniques and
mechanical processes are used in the design process to achieve a certain goal
and are normally not seen as ends in them self. Photographs, letters, colour, and
hand or machine generated images are all components used by designers in the
design process. Typography, one of these components, can be regarded as the
most used and sometimes misused element in the graphic design process.
Typography is used in all aspects of visual communications, and in conjunction
with appropriate images, can convey a very strong and precise message.
Gottschall (1989:1) defines typography as a vital element th.at makes electronic
and printed communication more effective and efficient. Typography forms an
integrating part in most facets of visual communication, whether it be purely
functional or aesthetic in nature. Legibility research is, amongst others, involved
in establishing how orthographic material can be deSigned and applied to solve
typographical problems. Miles A Tinker, an internationally recognised authority on legibility of print,
discusses the findings of past studies as well as his own in his book: Legibility of
Print. Some relevant aspects are:
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Italics are read somewhat slower than normal upright romans.
Visibility and perceptibility at a distance does not show any
agreement between the legibility of a type face and speed reading
tests.
Legibility is improved by more than seven per cent when indenting
the first line of a paragraph (Tinker 1963:64+65+127).
Results of Tinker's studies have provided material for seven books and nearly
two hundred publications. Tinker is also named by Zachrisson as one of the most
prolific writers on the subject of legibility (Zachrisson 1965:34).
In another interesting study a computer was used to simulate the neurological
structure of the human visual system. A digital computer model of human visual
processing was applied to characters with and without serifs. In the discussion
the researchers concluded that serifs were important and useful in the perception
of small 1 individual characters (Robinson, Abbamonte & Evans 1971 :359).
With the arrival of computers and electronic text, some of the legibility research
shifted towards this field. Foster and Bruce (1982:145) conducted experiments to
determine how easily upper cases should be read on a user's television screen
compared with lower case characters. The field of legibility research has greatly
been enlarged since the arrival of the microchip. Hartley (1987:1 3) argues that
much of the research on printed text is relevant when designing electronic text.
Owen (1991 :224-230) speculates that the traditional rules of typography will
become redundant in the design of electronic magazines. Type can move,
change colour, or flash to emphasize a point or to get attention. Electronic
magazines are designed with a computer, printed on compact disks, and read
from a visual display. Text, animation, video, sound, photographs and illustrations
are synthesized into a complex system, from which information can be retrieved
to be printed, read, or listened to. Two major obstacles associated with electronic magazines are the expensive hardware in delivering the magazine, and the poor
legibility of visual display units especially with small2 typefaces.
Researchers have calculated that an office worker must spend between sixty
thousand and eighty thousand hours reading documents, books and instructions
as part of his job during his career (Meyer 1987:7). Legible documents and books
are not only important for office workers, but must be a priority in educational
reading material. A tertiary student doing a three year course may have to read
between three and ten million words3, depending on the particular subjects during
the study period. The personal preferences of the printer and other aesthetic
reasons must thus be secondary to the legibility aspect of such material.
Research findings of psychologists, educators and typographers have provided
valuable information about factors of legibility. This information can now be used
by publishers and printers to design and manipulate typographical matter to make
reading material legible, inviting to read, and to communicate more effectively.
Knowing the factors that diminish legibility, Graphic Designers can also decide
how much legibility can be sacrificed for the sake of visual impact and aesthetic
considerations.