Chapter 7 Digital Prepress 149
enables users to specify different compression levels for
the various elements within a single image. For example,
EPS color image fi les embedded in a digital document
result in a very large fi le. EPS-JPEG compression
creates fi les for page composition software that are
signifi cantly smaller than standard EPS fi les. Images
vary in the amount of data that can be compressed
without affecting the visible quality. Experiment with
quality settings to determine the maximum compression
settings that do not perceptibly alter appearance. Since
data is lost in each compression/decompression cycle,
use JPEG compression at the maximum quality setting
and only on fi nal images, Figure 7-32.
Proofreading
A proof is any copy or art that is checked before
going into print. In traditional typesetting, the proof
is a galley pulled (printed) from the metal type or
a printout on phototypesetting paper. In today’s
electronic production systems, a proof is typically a
printout from a laser printer.
In traditional typesetting situations, manuscript
was edited and marked for type size and style before
being sent to the compositor. The compositor followed
all editing instructions and set the copy exactly as it
was written. After the copy was set, the proofreading
process was carried out to detect and mark any
typesetting errors. The marked proof would then be
sent back to the compositor for correction, and a
corrected proof would be produced and checked.
In digital composition methods, the author and
editor create the fi nal copy, which eliminates the
separate typesetting step. This does not eliminate
the need for proofreading, but changes the method
and approach. The typeset copy is not compared to
the original manuscript, since the typeset material
is the manuscript. It must still be read carefully for
errors and marked for corrections. After corrections
are made, the copy must be checked again. In
some operations, checking type corrections may be
combined with proofi ng the laid-out pages.
Proofreading Skills
A proofreader has the very important job of
making sure the fi nal product meets the standards
of expected quality and professionalism. In larger
publishing and printing facilities, people are hired
with expertise in proofreading. In smaller facilities, a
variety of people may have this responsibility. Every
printer, especially in a small plant, should be able to
read proofs.
The proofreader must be a meticulous person and
have the ability to accurately check individual letters
in words, as well as look for combinations of letters.
Proofreaders cannot scan a page, but must study
each word separately. If proofreading is done poorly,
the highest quality paper, best printing methods,
excellent content, and other favorable aspects of the
product will be ruined.
Proofreader’s Responsibilities
The typical duties of a proofreader include:
• Check the spelling of all words.
• Ensure word divisions or hyphenations are
correct.
• Verify that the style is consistent.
• Make certain that the size of type, line length,
and spacing specifi cations are followed.
• Check that copy has not been omitted or repeated.
Proofreader’s marks are widely used symbols
that single out and explain copy changes or errors,
Figure 7-33. The symbols are used to show when
something should be taken out, added, or changed.
Figure 7-32. JPEG compression should be used at
maximum quality to preserve the integrity of the data
being compressed.
lossy compression algorithms: A mathematical formula
for image compression in which data in an image that is
least perceptible to the eye is removed.
selective compression: A compression option that allows
the user to specify compression levels for different elements
within a single fi le.
proof: Any copy or art that is checked before going into print.
proofreading: The process of checking for typesetting
errors and marking them for correction.
proofreader’s marks: Widely used symbols that single out
and explain when something in typeset copy is to be taken
out, added, or changed.