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Subject:Re: Font Question, Multi use document From:"D. Margulis" <ampersandvirgule -at- WORLDNET -dot- ATT -dot- NET> Date:Tue, 28 Jul 1998 19:30:31 -0400
Bergen, Jane wrote:
> * Sans serif in a long line and on a full page (margin to margin on a
> letter-sized page) is really harder to read.
Jane raises an important point.
Line length has a tremendous impact on readability. When people wrote
text on a pica typewriter (10 characters to the inch), good practice was
to double-space copy and leave 1 1/2-inch margins. That leaves a line
length of 55 characters. One-inch margins raised this to 65 characters,
which Mr. Burnett would not have accepted back in 11th grade.
When you print out a page of 10 point Times Roman with 3/4-inch margins,
you are looking at a line of about 150 characters. In addition--and this
is critical--the lines are much closer together.
It turns out that the way we read is this: Our eyes lurch across the
line, taking in a chunk at a time and then moving on. When we get to the
end of the line, we execute a fairly subtle move, skipping back in one
lurch to the left, and we expect to pick up the beginning of the next
line. So the angle from the horizontal that we use when we execute that
last scan is important. If it is too small an angle, we are likely to
end up back on the line we just got done reading.
Book designers typically look for a line length of between 55 and 70
characters, and they select a leading (space added between lines) that
depends on the font but that is proportional to the font size. For Times
Roman, a common spec is 10/12 X 27-30 p. That is, 10 point type with two
points of lead, set on a line length of somewhere between 27 and 30
picas (4 1/2 to 5 inches). What I mean is that a single line length is
selected in that range, not that lines are going to vary within that
range. This is just for ordinary readable text. (Incidentally, to
maintain approximately the same character count with Arial, you can drop
down a point size or increase the line length.)
The reason you find people complaining about documents in 10-point type
and asking you to use a larger point size usually has to do with too
long a line rather than with their failing eyesight. People buy and
reads books and magazines every day that are set in 10- or 9-point type
and that include 8-point figure legends and callouts.