PRE-PRESS
TERMS:
Bleed: Artwork which extends beyond the edge of the trim area
of a print piece. The purpose of bleed is to safeguard against unsightly results
that might otherwise be created should the piece be trimmed slightly beyond
the intended trim area due to machine tolerance or human error.
Color Separation: The process of separating artwork into the
component printing colors to be used in production, most often the four process
colors: Cyan, Magenta, Yellow and Black, for later recomposition on press. During
separation, continuous tone artwork is broken down into tiny dots through the
aid of line screens to be specified by the printer.
CMYK: “Cyan, Magenta, Yellow, Black”’—A
color formulation standard used for print production.
Creep: The phenomenon by which spreads in the middle of a thickly
bound piece, especially bound by saddle stitching, often to “creep”
out from the center fold line of the piece due to successive layers of spreads
bound together. The result of creep may include the outer edges of middle pages
being inadvertently trimmed off in an unattractive manner. Creep should be accounted
for in pre-press by adjusting layouts either manually or via imposition software.
CTF: ‘Computer to Film’—A process by which
color separations are made from computer to Film, from which printing plates
are then burned using a refined photochemical process. Advantages include the
control afforded by seeing wet proofs made from film, examining films for problems
with Moïre patterns and Overprints, the ability to strip in or strip out
corrections or remake films affordably, and—In China—lower cost.
Disadvantages include the potential loss of quality due to one additional transfer
step and the extra time required to make films.
CTP: ‘Computer to Plate’— The process by
which color separations are made directly to printing plates from digital files,
without the aid of an intermediary step. Advantages include quality afforded
by eliminating the intermediary step, speed and convenience. Downsides may include
an inability to identify problems with Moïre patterns and Overprints, the
usual omission of accompanying wet proofs, which might allow identification
of costly mistakes before press time, and—in China—higher cost.
Digital proofs: Proofs made by a proofing method such as inkjet,
color laser, dye sublimation, or thermal wax to produce an approximation of
the color to be expected in the final product.
DPI: “Dots Per Inch”— The print industry
standard resolution metric. For printing in China, image files should be 300
dpi.
ICC Color Profiling: “International Color Consortium”
profiling—A Universal color management specification created to allow
color management across various platforms and vendors.
Live Area: The area inside the trim lines; The area of artwork
intended to be included in the final work.
Moïre Pattern: An unsightly criss-cross pattern created
when previously printed material has been scanned and color separated once again,
resulting in a conflict of screen angles.
Overprint: The process by which a color, quite often black
due its density, is surprinted on top of a previously printed color area. For
instance, small black or other dark type laid over a lighter color in a design,
should normally be overprinted, to avoid registration problems on press. When
providing PDF files, designers should ensure that the overprint setup is as
desired, as it will be difficult in the preflight stage for China Printing Solutions
to make changes to such setup.
PDF: “Portable Document Format” —A file format
developed by Adobe which permits linked images, fonts and color profiles to
be embedded in a single file which may be opened and sent through a RIP for
color separation without the native software package used to create the original
file. Extremely advantageous for avoiding inadvertent pre-press errors, but
difficult to change. Customers providing pdf files should be skilled in their
creation.
Printer’s Spreads: A page layout configuration which
is arranged in the order most convenient for printing, where up to 16 pages
are generally imposed together on a single large printing sheet.
Reader’s Spreads: A page layout configuration which mimics
the final order of pages as will be seen by the reader in the final piece.
RGB: “Red, Green, Blue”—A Color formulation
standard commonly used for viewing art on a computer monitor.
Trim: The point on each side of a printed piece at which the artwork
is intended to be cropped.
Wet Proofs: Proofs made by real printing ink, generally on
the paper to be used on the actual print run. Wet proofs in China are run on
hand presses using temporary mylar plates and, while they may still exhibit
discrepancies in registration or pressure-induced color shifts, are considered
by many to be the closest sensual equivalent to the final product possible.
Ideal for checking crossovers, construction, overprints and bleeds.