Glossary
Here is a list of common printing and graphic design terms.
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
A
AAs (author's alterations)
Client's changes and/or additions to copy after they have been typeset.
Achromatic colour
Colour with no saturation, such as white, black, or gray.
Additive colour primaries
Red, green, and blue (RGB). These colours are used to create all other
colours with direct (or transmitted) light (for example, on a computer
or television screen). They are called additive primaries because when
pure red, green, and blue are superimposed on each other, they create
white. Refer to subtractive colour primaries.
Aliasing
Visibly jagged steps along angles or object edges due to sharp tonal contrasts
between pixels.
Alignment
Placement and shape of text relative to the margins. Alignment settings
can be centered, flush left, flush right, justified, ragged right, etc.
Alpha channel
An 8-bit, gray scale representation of a Photoshop image, often used for
creating masks that isolate part of an image.
AM screening
Amplitude-modulated screening. Same as traditional halftone screening.
Compare with FM screening.
Annotation
Non-printing layers in some page layout programs used to provide written
instructions on certain aspects of an electronic file.
Anti-aliasing
In computer graphics, the smoothing of the jagged, "stairstep"
appearance of graphical elements. See also jaggies.
Artwork
Any analog or digital image, text or graphics used for printing reproduction.
Ascender
The part of a letter that rises above the main body, such as the rising
strokes of the letters "d" and "k." Refer to descender
Aspect ratio
In computer graphics, ratio of width to height of a screen or image frame.
Automatic Text Flow
Used in desktop publishing, it allows text matter to flow from one column
to the next on each page and from one page to the next in a document automatically.
It eases the pain of making significant copy changes to a long document.
Automatic Picture Replacement
A linking process where a low resolution image or low resolution placeholder
(FPO) is automatically replaced by a high resolution image just before
a document is sent to the imagesetter. This allows page layout handlers
to work with smaller files without overloading the processors. Also known
as AIR or OPI.
B
Banding
White bands which can be produced if data is sent too slowly to recorders
that cannot stop/start successfully. The media continues to feed even
though no image is available to print, resulting in white bands in the
output. Stripes of colour that occur when too few colours are available
to achieve a smooth colour blend. A visible stair-stepping of shades in
a gradient.
Baseline
The invisible line which all characters in a line of type rest upon.
Batch scanning
The sequential scanning of multiple originals using previously defined
and unique settings for each.
Bezier curve
In computer graphics, a bezier is a curved line described by two end points
and two or four control points. The end points are the ends of the curve
itself. The control points (or levers) determine the shape of the curve,
but are not on the curve itself.
Bilevel
A form of image containing only black and white pixels, a 2-bit image.
Bindery marks
Press Sheet markings that indicate how the sheet should be cropped, folded,
collated, or bound.
Bit depth
The number of bits in each pixel of an image. Also refers to the amount
of data per pixel for displaying on a computer monitor. Bit depth sets
the maximum number of discrete colours or shades in each pixel; hence,
the greater the bit depth, the more vivid and realistic colour and greyscale
images will appear.
Bitmap
An image formed by a matrix of visible or invisible dots (bits). On a
computer screen, the dots are formed by pixels. Unlike vector objects
or Bezier curves, bitmaps are resolution dependent. See also raster image.
Black point
A movable reference point that defines the darkest area in an image, causing
all other areas to be adjusted accordingly.
Bleed
Text or art that extends beyond the trim page boundaries, or the crop
marks, on one or more sides of a page. Part of a printed image that extends
beyond the page boundary. When the page is trimmed to size, the "bleed"
extends to the absolute edge of the paper, preventing any show-through
of the paper colour.
Blend
See Graduated fill.
Blind embossing
The technique of creating an image on paper by stamping the paper with
a die, creating a visible raised effect, without applying ink to the image
(hence, the designation of "blind").
Blueline
Also known as blueprint. A one-off print made from stripped-up film or
mechanicals, used to confirm position of image elements. Bluelines are
often used as final proofs for single and spot colour jobs, or to show
how the final job will fold or bind.
Blueprint
Refer to Blueline.
Body Copy
Text matter that comprises the major content of an article or publication
other than mastheads, headlines, sub-heads, call-outs, charts and graphs.
Boxes
This technique is to highlight or isolate important words or graphs from
secondary copy surrounding it. Boxes also create interest and give the
reader's eye a break from long passages and monotonous amounts of text.
Brightness
The relative lightness of an image. Computers represent brightness using
a value between 0 (dimmest) and 255 (brightest).
Bromide
A contact print made by exposing a photographic paper (originally bromide
paper) to a light source through a film negative. Before the advent of
computer generated artwork, bromides were commonly used as camera-ready
artwork.
Bullet
Bullets can be solid dots or squares, open dots, or another tiny iconic
symbol that is used to enhance a list. Bullets are normally set in a slightly
larger point size than the text they accompany and should always be used
in a list of no less than five items. Bullets are visually most effective
when used with hanging indents.
C
Calibration
With regard to recorders and imagesetters, the process of adjusting the
device so it correctly reproduces the desired halftones, tints, and so
on. See also Linearisation.
Calibration bars
A strip of varying shades usually ranging from 0% to 100% (in 10% increments)
on film, proofs, and press sheets. Prepress service providers use calibration
bars to measure and control screen percentages for printing and proofing.
Call-Out
A call-out is a short phrase or line of type that helps identify important
elements of a graphic or illustration. A connecting line or arrow is often
used with a call-out.
Camera-Ready Copy
Black and white artwork that is meant to be processed by shooting it on
a process camera or scanned and converted to negatives and used to make
printing plates. On a direct-to-plate system, the black and white artwork
would be converted directly from the art to the printing plate. Used as
a generic term for a mechanical, film negative or positive, or any material
that is ready to be photographed for the purpose of generating printing
plates.
Caption
A caption is a sentence or more used to summarize the importance of charts,
graphs, illustrations, photographs, or tables. Captions identify the people
in photographs and relate the photo or graphic item to the surrounding
body copy. A photograph should always have a caption.
Cast
An unwanted tinge or shade of colour present in an image.
Center marks
Press marks that appear on the center of all sides of a press sheet to
aid in positioning the print area on the paper.
Channel
Information about a single process or spot colour contained within an
image file. An image may have up to 16 channels.
Choke
Refer to Trap
Chroma
A synonym for colour or hue.
Chromatic
Perceived as having a hue, not white, gray or black.
Chromaticity
A measure of the combination of both hue and saturation in colour produced
by lights.
Cicero
A unit of measurement in the Didot system, commonly used in Europe. A
cicero is slightly larger than a pica and is approximately 4.55 millimeters.
CIE
Commission Internationale de l'Éclairage, the international body
that sets standards for illumination and developed the CIE colour models.
CIE colour models A family of mathematical models that describe colour
in terms of hue, lightness, and saturation. The CIE colour models include
CIE XYZ, CIELAB, CIELUV, and CIE xyZ.
Clip art
Illustrations and designs collected and usually sold commercially.
Click Art
Electronic art files that are already on a disk are called click art.
Clipping
The conversion of all tones lighter than a specified gray level to white,
or darker than a specified grey level to black, causing loss of detail.
This also applies to individual channels in a colour image.
Clipping path
The boundary of a graphical mask (created by points and straight or curved
lines) used to screen out parts of an image and expose or print other
parts. Only what is inside the clipping path is displayed or printed.
A series of Bezier curves drawn around a particular area of an image to
isolate it from its background, so that it appears to be masked or silhouetted
when placed in a page-layout program. Typically performed in Adobe Photoshop.
CMS
Colour management system. This ensures colour uniformity across input
and output devices so that final printed results match originals. The
characteristics or profiles of devices are normally established by reference
to standard colour targets.
CMYK
A colour mixing model consisting of the four process colours used in printing:
cyan, magenta, yellow, and black. A comprehensive array of colours can
be achieved by combining certain percentages of these four primaries.
White is achieved by letting the paper show through where white is required.
Colour
Light waves that reach the viewer's eye by transmission (through an object
between the viewer and the light source) or by reflection (when light
waves bounce off an object). All substances, whether transparent or opaque,
absorb some wavelengths while letting others pass through or bounce off.
A red apple looks red because it absorbs all colours in white light except
red, which it reflects. White objects reflect all and black objects absorb
all light waves (at least in theory).
Colour, additive
Colour produced by mixing coloured lights. In projected light, each colour
is created by adding one colour of light to another. All colours can be
made by a mixture of red, green and blue light.
Colour overlay
A sheet of film or paper whose text and art correspond to one spot colour
or process colour. Each colour overlay becomes the basis for a single
printing plate that will apply that colour to paper.
Colour proof
A representation matching the appearance of the final printed piece. Includes
colour laser proofs, colour overlay proofs, and laminate proofs. A representation
of what the printed composition will look like. The resolution and quality
will vary greatly depending on the proofing device. These can be provided
during the various stages of page construction.
Colour separation
In four colour process printing, the process of transforming colour artwork
into four components corresponding to the four process colours. In spot
colour printing, the process of transforming artwork into components corresponding
to each spot colour required in the printed piece. Each component used
in preparation for making printing plates that correspond to the specific
ink colour.
Colour, subtractive
Colour produced by mixing pigments (such as inks or paints). Pigments
absorb (or subtract) all the colours from the reflected light except for
the colour we see.
Colour bars
Rectangles of colour printed on colour proofs to check the ink densities
and other technical factors required to conform to quality standards.
Colour break
Artwork prepared so as to indicate which elements print in which ink colour.
Copy and art for each colour may be pasted on separate boards, pasted
on on overlays, or indicated in pencil on an overlay sheet of tissue paper.
Colour cast
An overall colour imbalance in an image, as if viewed through a coloured
filter.
Colour conversion
Black-and-white version made from a colour photograph or other original.
Colour correction
The adjustment of colours in any photographic, electronic, or manual process
to obtain a correct image by compensating for the deficiencies of process
inks, colour separation, or undesired balance of the original image.
Colour key
A set of four acetate overlays, each utilizing a halftone consisting of
one of the four process colours used for proofing colour separations.
Colour lookup table
A table of values, each of which corresponds to a different colour that
can be displayed on a computer monitor or used in an image. For example,
an indexed colour image uses a colour lookup table of up to 256 colours.
Colour matching
Specifying Pantone or process colours to produce a desired colour from
a previously printed piece or other colour original.
Colour proof
Hard copy in colour (for example, a laserprint, inkjet print or colour
key) used to check before a job before reproduction.
Colour saturation
The amount of a hue contained in a colour; the greater the saturation,
the more intense the colour.
Colour space
A scheme of representation for colour images, such as CMYK or RGB. Colour
are represented as a combination of a small set of other colours or by
other parameters (like hue, saturation, and brightness).
Colour wheel
A circle that displays the spectrum of visible colours. It provides a
graphic representation of the relationship between primary and secondary
colours with successive colour mixtures and tonal values.
Colourimeter
A light-sensitive device for measuring colours by filtering their red,
green and blue components, as in the human eye. See also spectrophotometer.
Combination signatures
Signatures of different sizes inserted at any position in a layout.
Comp
Comprehensive artwork used to represent the general colour and layout
of a page.
Complementary colour
The inverted hue of a colour (the one that is diametrically opposite on
a colour wheel). For example, yellow is the
complementary colour of blue.
Composite proof
A version of an illustration or page in which the process colours appear
together to represent full colour. When produced on a monochrome output
device, colours are represented as shades of gray. Composition Composition
is the process of keyboarding and combining typographic elements into
pleasing page layouts for print production.
Compression
The use of various software designed to reduce the size of a digital file.
See also lossy and non-lossy.
Condensed type
Type in which the individual characters are narrower than normal so that
more characters can fit on a single line. When the set width of a font
has been shortened, the font will be more narrow—allowing more characters
to fit on any given line length. Fonts should be condensed by using a
true "condensed" version of a typeface. Condensing type by using
the "attributes" selection screen of a page layout program increases
the risk that the outputting or dtp equipment will not recognize the font
or ignore it completely.
Continuous-tone (CT also contone) image
Any colour or greyscale image which has not been converted to halftone
dots for reproduction. Photographs, paintings and charcoal drawings are
prime examples of continuous tone images
Contract Proof
A proof created by the printer to be shown to the customer as a representation
of the final colours of a printed piece and subsequently signed by the
customer to indicate that the printed piece will be acceptable if it matches
the signed proof
Contrast
The difference between the dark and light values in an image. Images with
a great deal of contrast contain mostly very dark and very light values,
while low-contrast images contain mostly medium gray values.
Copyfitting
Copyfitting is the process of writing or editing articles to fit into
a predetermined space allowance. Good copyfitting results in evenly filled
columns and pages with the proper amount of white space.
Creep:
The movement of a press sheet while traveling through a press. Sometimes
associated with shingling.
Cromalin
see Proof
Cromacheck
see Proof
Crop marks
Short, fine lines used as guides for final trimming of the pages within
a press sheet. Short, fine lines that mark where a printed page should
be trimmed when it is printed on paper that is larger than the image area.
Cropping
Cropping is the process of eliminating irrelevent or excessive background
content of photographs. Cropping enhances the focus of photographs and
allows the designer to change the shape of the original photo.
Custom printer description file
A file containing information specific to a type of output device; used
in conjunction with a standard PPD file to customize the printing process.
D
Dandyroll
Cylinder on a paper machine for creating finishes, such as wove, laid,
or linen, and for adding watermarks.
Data underrun
The result of a raster image processor (RIP) failing to supply data to
an output device quickly enough. If the output device cannot stop/start
successfully, banding or other negative effects may occur.
DCS
Acronym for Desktop Colour Separation, a version of the EPS file format.
DCS 1.0 files are composed of five PostScript files for each colour image:
cyan, magenta, yellow, and black file, plus a separate low-resolution
FPO, image to place in a digital file. In contrast, DCS 2.0 files can
have a single file that stores process colour and spot colour information.
A preseparated image file format, developed by Quark, Inc., consisting
of five parts: four process colour separation files (containing the cyan,
magenta, yellow, and black components of the image) and a composite EPS
placeholder file. A variation of the EPS file format for CMYK images where
the process colour information is stored in four separate files. A fifth
"master" file is used for placement in a page layout. This format
is sometimes used by prepress vendors instead of OPI, or APR images. The
master file can be sent to the designer for placement in the layout.
Decompression
The expansion of compressed image files. See also lossy and non-lossy.
Densitometer
A device used throughout the printing process to measure the amount of
light passing through or reflecting from a given medium.
Die line
In a digital file, the outline used to create a device for cutting, stamping,
or embossing the finished printed piece into a particular shape, such
as a rolodex card.
Density
The ability of an object to stop or absorb light. The less the light is
reflected or transmitted by an object, the higher the density.
Density range
The range from the smallest highlight dot the press can print to the largest
shadow dot it can print. Density range also describes the capacity of
a scanner to read detail in the shadow and highlight areas of a continuous
tone image. The greater the scanner range, the more detail at either end
of the scale. Scanners with a short density range characteristically produce
noise in the darkest shadow areas. Refer to noise.
Descender
That part of a letter that drops below the baseline, such as the lower
strokes of the letters "g" and "p." Refer to ascender.
Descreening
Removal of halftone dot patterns during or after scanning printed matter
by defocusing the image. This avoids moire patterning and colour shifts
during subsequent halftone reprinting.
Dichroic mirror
A special type of interference filter, which reflects a specific part
of the spectrum, whilst transmitting the rest. Used in scanners to split
a beam of light into RGB components.
Digital
A format which is recognizable and readable by a computer system.
Digital Photography
Digital cameras use a CCD sensor that captures light and converts it into
electrical signals, when are then converted into digital data. Images
may be temporarily stored in random access memory (RAM), in-camera storage
media, or moved directly to a computer's drive.
Digitize
Convert information to computer-readable form. Digitized typesetting is
the creation of typographic characters by the arrangement of black and
white pixels.
Dimensional stability
Degree to which paper maintains its size and shape in the printing process
and when subjected to changes in moisture content or relative humidity.
Dingbat
A decorative character.
Direct-to-plate
Direct exposure of image data onto printing plates, without the intermediate
use of film.
Direct-to-press
Elimination of intermediate film and printing plates by the direct transfer
of image data to printing cylinders in the press.
Display type
Type set larger than the text to attract attention.
Dithering
A technique used in computer graphics to create the illusion of varying
shades of gray or additional colours by distributing the screen pixels
or imagesetter dots of an image. Dithering relies on the eye's tendency
to blur spots of different colours by averaging their effects and merging
them into a single perceived shade or colour.
Dmax
The point of maximum density in an image or original.
Dmin
The point of minimum density in an image or original.
Document
Computer file created with an application program.
Dot
In printing, a small spot which combines with other dots in a matrix of
rows and columns to form characters or graphic elements. Refer to halftone
Dot gain
In halftone printing, the tendency of the ink used to create halftone
dots to flow outward as it is absorbed by the paper. Too much dot gain
can create a cloudy or dark image. A phenomenon that results due to the
tendency of wet ink to spread when it contacts paper. This results in
a slightly larger dot than appears on the printing plate itself, and in
some cases may cause images to darken or appear "muddy." Image
files should be prepared in such a manner so as to allow for dot gain,
a process known as gain compensation.
Dot shape
The shape of the dots that make up a halftone. Dot shapes can be round,
square, elliptical, linear, etc.
Downloadable font
A font not resident in a printer's memory that must be sent to the printer
in order to print a document containing that font.
Down sampling
The process of acquiring a low-resolution copy of an high-resolution image
for layout purposes only. The reduction in resolution of an image, necessitating
a loss in detail.
DPI
Dots per inch. A measure of screen and printer resolution that is expressed
as the number of dots that a device can print or display per linear inch.
The number of dots in a linear inch (as opposed to a square inch). Therefore,
a 600-dpi laser printer prints 600 dots per linear inch, or 360,000 (600
x 600) dots per square inch. DPI is also known as resolution, as in "What
is the resolution of your printer/scanner/TIFF file/monitor?" Printer,
scanner, image and monitor resolution are all typically expressed in terms
of DPI. However, since image files are made up of pixels, and since monitors
display pixels rather than dots, image resolution and monitor resolution
should technically be expressed in PPI (pixels per inch). Refer to LPI
(lines per inch)
Drop cap
A decorative capital letter at the beginning of a paragraph that hangs
below the top line of the paragraph and occupies space of more than one
line.
Drop shadow
A coloured or shaded box or character offset and placed behind an identical
box or character to give a shadow effect.
Drum scanner
Early drum scanners separated scans into CMYK data, recording these directly
onto film held on a second rotating drum.
DSC
Acronym for Document Structuring Conventions, a set of organizational
and commenting conventions for PostScript files designed to provide a
standard order and format for information so applications that process
PostScript can easily find information about a document's structure and
imaging requirements. These conventions allow specially formatted PostScript
comments to be added to the page description; applications can search
for these comments, but PostScript interpreters usually ignore them.
Duotone
A halftone greyscale image rendered in two colours, one of which is usually
black. This process uses the same image on both plates with the exception
of setting the screen angles differently to avoid moir? patterns and the
density range is shortened on the darker colour to allow the lighter colour
to show in the highlight and midtone areas. This gives the image tonal
and colour interest and gives the illusion of added depth. This is a very
useful design alternative for two-colour print jobs containing grayscale
images.
Dye sublimation
A printing process using small heating elements to evaporate pigments
from a carrier film, depositing these smoothly onto a substrate. Used
primarily for colour proofs and comps.
Electrostatic printing or copying
Printing process in which an image is created by applying an electric
charge to a carrier, attracting magnetic ink (toner) to the image, and
transferring it from the carrier to paper with heat and pressure. (see
also Xerography)
Ellipsis
The ellipsis is a set of three dots which look like a series of three
periods. They are used to indicate missing copy when placed between two
sentences or phrases. They are commonly used when paraphrasing long quotation.
They can also be used in pairs as a "continuation technique"
when you want to lead the reader into other copy. But, don't forget to
place the second set of ellipsis before the final connecting copy so the
reader knows where to go.
Em
Unit of space (width) equal to the point size of the type.
Em Dash
An em dash is used to abruptly change a thought within a sentence or to
connect two different thoughts within a sentence. The actual length of
an em dash is approximately four times the length of a hyphen and is relative
to the set width of the font which you are using. Em dashes received their
name due to the fact that they are equivalent to the width of the capital
letter em (M).
Em Space
An Em space is a fixed amount of blank space equivalent to the width of
a capital letter em (M). Em spaces are frequently used for paragraph indents
and bullet item indents because they are fixed units. Em spaces are relative
to the set width of the font being used.
En
Half an em.
En Dash
An en dash is used to denote continuation; as in "pages 4-5"
and "1966-1995." The actual length of an en dash is approximately
two times the length of a hyphen and is relative to the set width of the
font which you are using. En dashes received their name due to the fact
that they are equivalent to the width of the capital letter en (N). An
en dash is one-half the width of an em dash.
En Space
An En space is a fixed amount of blank space equivalent to the width of
a capital letter en (N). En spaces are frequently used when a fixed amount
of space is needed, but less space than the more commonly used em space.
En spaces are relative to the set width of the font being used. An en
space is one-half the width of an em space.
Emboss
To stamp a raised area or image into paper with metal dies, usually combined
with a printed image. (To stamp an indentation with metal dies is to deboss
the image)
Emulsion
A thin photo-sensitive coating (usually containing silver halides) that
is applied to a base substrate to produce photographic film or paper.
When the emulsion is exposed to the appropriate light source and developed
in the appropriate chemical developer, an image is produced. Developing
removes the unexposed silver halides from the emulsion.
Encapsulated PostScript (EPS)
A file format that stores PostScript information in an image file so that
it may be transferred as a unit to a suitable page layout or drawing program
or used for preparing images for later typesetting. An encapsulated PostScript
file has two parts: a low resolution bitmap picture of the screen and
a full PostScript description to pass on to a suitable printer.
EPS
See Encapsulated PostScript.
EPS 5
Another term used for DCS. Refer to DCS
Errata
A list of errors in a book which are of sufficient importance to be called
to the attention of the reader.
Euclidean dot shapes
Round, elliptical, square, or linear halftone dots that invert with their
cell after 50% intensity. This strategy helps reduce dot gain problems
sometimes experienced with elliptical, square, and linear dots.
Eyemark
A small block of print used to trigger packaging equipment.
Expanded
When the set width of a font has been lengthened, the font will be wider,
allowing fewer characters to fit on any given line length. Fonts should
be expanded by using a true "expanded" version of a typeface.
Expanding type by using the "attributes" selection screen of
a page layout program increases the risk that the outputting or dtp equipment
will not recognize the font or ignore it completely.
Exploded view
A type of illustration that shows a structure with its parts separated
but drawn in relation to each other.
Export
To transfer information from the current program to another location or
program. See import.
Exposure
A ratio of the intensity of a light source and length of time photo-sensitive
material is subjected to the light source. The measurement of exposure
is a prominent factor in controlling the lasers that are at the heart
of imagesetters, platesetters and computer-to-press imaging devices.
F
Facing pages
Two pages that face each other in a printed publication, comprised of
the verso (left) and recto (right) page of an opened book.
Family
A family of type is the complete font set with all its related attributes.
One family can include: roman, italic, bold, bold italic, black, black
italic, light, light italic, thin, thin italic, plus all the condensed
and expanded versions of the previously listed.
Feathering
The progressive bleed-off at the soft edge of an image so that it blends
with the underlying image or background colour.
Film assembly
See Stripping.
Film negative
Film containing an image in which the values of the original image are
reversed. Film negatives are typically output from imagesetters and are
used to create printing plates. Refer to Film Positive.
Film positive
Same as film negative, except that the image is not reversed. Usually
used when the film is to be duplicated, rather than directly photographed
to create printing plates.
Film recorder
Used in reference to colour transparency recording devices, and sometimes
also to imagesetters.
Flat
Individual film assembled onto a film carrier readied for contacting or
Platemaking.
Flatbed scanner
Any scanning device that incorporates a flat transparent plate, on which
original images are placed for scanning. The scanning process is linear
rather than rotational.
Flexographic printing
Printing on a press using a rubber plate that stretches around a cylinder,
making it necessary to compensate by distorting the plate image. Flexography
is used most often in label printing, often on metal or other non-paper
material.
Flip
To rotate an image along either its horizontal or vertical axis.
Flood
To completely coat a press sheet with ink or varnish (as apposed to pattern
or spot varnish which is a defined image).
Flush
Aligned or even with (in reference to type alignment).
Flush Left
Aligned along the left edge or margin.
Flush right
Aligned along the right edge or margin.
FM screening
Frequency-modulated screening. A type of screening that employs irregular
clusters of equally sized CMYK pixels to represent continuous-tone images.
The placement of these pixels, although seemingly random, is precisely
calculated to produce the desired hue and intensity. This process differs
from traditional halftoning in which the distance between CMYK dots remains
constant while dot size varies to create the desired hue and intensity.
Compare AM screening. See also Stochastic Screening.
Fold marks
Dotted or dashed lines on camera-ready art that indicate where to fold
the printed piece.
Folding dummy
A template used for determining the page arrangement on a form to meet
folding and binding requirements.
Folio
A printed page number.
Font
A set of letters, numbers, punctuation marks, and symbols that share a
unified design. The design is called a typeface. A group of related typefaces
is a type family. A font is the specific name applied to a particular
typeface style. Examples of font names are Helvetica, Times, Americana,
and Zapf Chancery.
Footer
The information about a publication, such as its title, date, issue or
page number is a footer when is consistently appears at the bottom of
each page of the document.
Footnote
A footnote is a numbered passage which amplifies specific information
on the page and provides direction about how to find sources or related
reading.
Form
The front or back of a signature.
Format
The overall appearance of a publication, including page size, paper, binding,
length, and page-design elements such as margins, number of columns, treatment
of headlines, and so on.
For position only (FPO)
A photocopy, photostat, or low-resolution electronic copy of an image
or piece of art positioned on the camera-ready page to indicate the position
of the actual art to be stripped in by the printer or inserted by the
system during prepress processing. a term applied to low-quality art reproductions
used to indicate placement and scaling of an art element on mechanicals
or camera-ready artwork. In digital publishing, an FPO can be low-resolution
TIFF files that are later replaced with high-resolution versions. An FPO
is not intended for reproduction but only as a guide and placeholder for
the prepress service provider.
Fountain solution
A solution of water, gum arabic, and other chemicals used to repel ink
from non-printing areas of the lithographic plate.
Four-colour process
The most common full-colour printing process which uses colour separation
to produce one image for each of the four process colours (cyan, magenta,
yellow, and black). Each colour is then overprinted to reproduce the full
colour of the image.
Frame
An outline between abutting colour areas.
Frame-grabbing system
A combination of hardware and software, designed to capture individual
frames from video clips for further digital manipulation, or consecutive
replay on computer platforms.
Frequency (Halftone Screen Frequency)
The spacing of the dot matrix in a halftone image, usually expressed as
lines per inch (lpi). Optimum halftone screen frequency is dependent on
the type of imaging device used to reproduce the halftone. In practical
terms it varies from 55 lpi for silkscreen printing to 200 lpi for high-end
offset printing.
G
Gain compensation
The process of preparing an image file to compensate for the increase
in dot size, known as dot gain that occurs when wet ink spreads on paper.
Adjustments to compensate for dot gain are typically performed in Adobe
Photoshop or a similar image editing program.
Gamma
A measure of contrast that affects the mid-range grays (midtones) of an
image. Gamma is often expressed as a curve. Technically, a numerical representation
of contrast in an image. Adjusting the gamma, which is what you are doing
when you move the middle slider in Photoshop's "Levels" dialog,
allows you to correct midtones without noticeable changes in the highlight
and shadow areas.
Gamma correction
The correction of tonal ranges in an image, normally by the adjustment
of tone curves.
Gamut
The range of colours that a device can reproduce. The eye, the camera,
the computer monitor, the toner-based colour printer, the inkjet printer
and the four-colour printing press all have different colour gamuts. The
human eye has the widest gamut and the printing press has the narrowest.
Gamut mapping
The process of colour matching in which differences in colour gamuts between
the source device and the target device are taken into consideration.
Gamut simulation
The process by which a device with a wider gamut is programmed to emulate
behavior of a device with a narrower gamut.
Gang scanning
True gang scanning means mounting a number of originals on the scanner
and scanning all at the same exposure. Advances in scan software now allow
multiple images to be mounted on the scan bed and exposure, cropping,
colour mode and other scan parameters to be applied to each individual
image.
Gatefold
A four-page insert or cover with foldouts on either side, making the equivalent
of 8 pages.
GCR
Gray component replacement. A colour separation technique that uses black
instead of combinations of cyan, magenta, and yellow in reproducing the
gray components of colours. This provides a more economical use of inks
and improved ink application. A technique for minimizing ink coverage.
Ghost
When an image is screened back or shaded down in intensity, it is called
a ghosted image. Both full-colour and black and white images can be ghosted.
Ghosting
Light marks in a printed image caused by an adjacent heavy image depleting
the ink on the inking roller. Smaller presses with few rollers in the
ink train are most subject to this problem, although some designs will
cause ghosting even on the largest press.
GIF
Graphic Interchange Format. A platform-independent image file developed
by CompuServe that is commonly used to display and distribute images on
the Internet. A compressed digital image format widely used for electronically
published images on the Internet. Any single image may only contain a
maximum of 256 different colours, generally considered inadequate to represent
photos. Pronounced Jiff.
Gothic-style typefaces
San serif typefaces.
Gradient fill
See graduated fill.
Graduated colours
A graded series of colours that changes progressively from one colour
to another or from light to dark or dark to light within the same colour.
See also Vignette
Graduated fill
An area in which two colours (or shades of gray) are blended so as to
create a gradual change from one to the other. Graduated fills are also
known as blends, gradations, gradient fills, and vignettes.
Grain
In paper, the direction in which fibers line up. Paper grain is a significant
factor in a variety of operations such as folding, scoring and paper handling
in printing and finishing equipment.
Graphic Accents
Graphic Accents emphasize and organize words, illustrations and photographs.
Boxes, drop shadows, indents, lines, rules, screens and icons are considered
graphic accents.
Graphics Linking
A page layout term that refers to the way placed graphics files are managed
by software. When a graphic is placed on a page, it appears there but
does not become part of the page layout file. The page layout software
keeps track of the location of the graphics file (the link) and will download
that file when the page layout is printed.
Grey balance
The balance between CMY colourants required to produce neutral greys without
a colour cast.
Grey component replacement
See GCR.
Grey levels
Discrete tonal steps in a continuous tone image, inherent to digital data.
Most digital continuous tone images will contain 256 grey levels per colour.
Greyscale
The representation of colours in varying shades of gray - usually 256
shades in digital artwork.
Grid
A grid is the defining of headline positions, column length and width,
placement of headers and footers and and any other predetermined placement
of photographs or graphic elements on a page. A series of nonprinting
horizontal and vertical rules assist in creating and maintaining a grid
for page layout.
Grind-off
The trim at the back (or spine) of a signature, or of two or more gathered
signatures, in preparation for perfect binding.
Gripper
The part of the press or printer that holds the paper and guides it through
the press. Also, the edge of the paper so held.
Gutters
Extra space between pages in a layout. Gutters can appear either between
the top and bottom of two adjacent pages or between two sides of adjacent
pages. Gutters are often used because of the binding or layout requirements
of a job: for example, to add space at the top or bottom of each page
or to allow for the grind-off taken when a book is perfect bound. Gutters
are the white spaces which appear between columns of type. Gutter widths
should be wide enough to clearly define columns and narrow enough to not
lose the reader. Gutters are also placed between multiple images on a
press sheet for a variety of finishing processes.
H
Hairline rule
A very thin typographic rule.
Halftone
The rendering of an image in a series of dots whose size differs relative
to the tonal density of the image. When seen from a normal viewing distance,
and without magnification, the dots are seen as areas of differing tonal
values. See also AM screening, FM screening, screening and frequency.
Halftone resolution
The spacing of the dot matrix in a halftone image, usually measured in
lines per inch (lpi). More correctly referred to as the frequency or halftone
frequency.
Halftoning factor
The formula used to determine the optimum graphic resolution (pixels per
inch) of an image based on the screen frequency used on the reproduction
device. The image resolution in pixels per inch should be twice the screen
frequency of the reproduction device at actual reproduction size. For
example, a photo to be reproduced at 150 lpi on the press should be scanned
at 300 ppi at reproduction size.
Halo
A light line around object edges in an image, produced by the Unsharp
Masking (sharpening) Technique. This technique uses the contrast between
the edges of tonal areas of a continuous tone areas as a basis for applying
the halo. The halo creates a visual separation between the tonal areas
and makes the image look sharper or more in focus.
Hang
To place characters outside the left margin.
Hanging indent
A paragraph style in which the left margin of the first line extends beyond
the left margin of subsequent lines, or put another way, all subsequent
lines are indented more than the first line of the paragraph. Bulleted
and numbered items are visually most effective when they use hanging indents.
Hard copy
Images intended for reproduction and which have been supplied as prints
rather than digital files. See also soft copy.
Harlequin Precision Screening (HPS)
A set of screening algorithms developed by Harlequin Incorporated that
precisely controls the accuracy of screen angles and frequency to reduce
moire patterns.
Head
A head or headline is an enlarged phrase which gives the reader a preview
of the content to follow. Heads are very important elements because they
motivate the reader to continue reading the associated material.
Header
The information about a publication; such as its title, date, issue, or
page number is a header when is consistently appears at the top of each
page of the document.
Headline
The title of an article or story.
Heavy Ink Coverage
When over 30% of a sheet has ink coverage on it, the order is considered
to have heavy ink coverage.
High key
A light image that is intentionally lacking in shadow detail.
Highlight
The lightest (brightest) areas of an image; usually refers to areas with
less than or equal to a 10% halftone dot. Areas with no visible halftone
dot (like sunlight reflecting off a chrome bumper) are known as specular
highlights (specular light being the opposite of diffuse light). Refer
to shadows, midtones.
Histogram
A chart displaying the tonal ranges present In an lmage as a series of
vertical bars. A graphic representation of the distribution of light and
dark pixels in an image, which provides the information necessary to make
tonal adjustments. In Adobe Photoshop, it's accessed via the "Image"
menu.
Hue
The visual attribute of a colour that allows it to be classified as red,
blue, yellow or any intermediate between contiguous pairs of these colours.
Hyphenation
In typographical usage, a hyphen is placed at the end of the syllable
that remains on the first line when words are too long to fit on a single
line and are broken between two lines. Hyphenation can be automatic in
page layout programs but this hyphenation is based on a rudimentary hyphenation
dictionary contained in the layout software. For quality work, hyphenation
should be corrected manually to repair bad word breaks and enhance copyfitting.
Hyphenation can also be turned off if no hyphens are preferred.
Hyphenated Zone
The hyphenation zone is the space near the column's right edge which will
allow hyphenation. Long hyphenation zones result in fewer word splits
than short hyphenation zones.
I
Icon
In graphical environments, a small graphic image displayed on the screen
to represent an object that can be manipulated by the user.
Image area
The area of a printed piece wherein an image can be placed without danger
of being marred by accidental cropping, folding or other finishing processes.
Sometimes referred to as a safety area.
Imagesetter
A digital recording device that uses a laser to image photosensitive film
or paper. Imagesetters are used for creating artwork for reproduction.
Most imagesetters are PostScript-compatible and use a dedicated raster
image processor (RIP) to process the digital information into code to
drive the laser.
Imaging
The process of producing a film or paper copy of a digital file from an
output device (such as an imagesetter or printer).
Import
To bring information into the current program from another location or
program. See export.
Imposition
The process of arranging individual pages on a digital or analog form
to construct a signature so the pages will be in proper sequence after
printing, folding, and binding. Also the placement of multiple images
on a form or press sheet to produce the job in the most economical manner.
Impression
The transfer of an individual image to an individual side of a sheet of
paper. Each colour represents a separate impression, so printing one side
of one sheet in four colour process equals four impressions.
Impression cylinder
Cylinder of an offset press that squeezes the paper against the blanket
cylinder carrying the image. (In toner devices, this is accomplished by
a transfer cylinder or belt).
Indent
The most common indent is at the beginning of a paragraph when the first
line is "set-in" from the left edge of the column. An indent
can be placed on the left side only (as in paragraph beginnings) or on
the left and right sides of copy (when a block of text needs to be set
apart from the rest of the paragraph).
Indexed colour image
A single-channel image, with 8 bits of colour information per pixel. The
index is a colour lookup table containing up to 256 colours. A pixel colour
system that uses a limited number of distinct colours (usually 256 colours)
to represent a digital image, rather than describing a colour using bit
depth.
Ink-jet printer
A nonimpact printer that fires tiny drops of ink at the paper to create
characters or graphics.
Inside margin
The space between the binding edge of the page and the text.
Interpolated resolution
See optical resolution.
Interpolation
In the image manipulation context, this is the increase of image resolution
by the addition of new pixels throughout the image, the colours of which
are based on neighbouring pixels.
Isometric view
A display method that shows three-dimensional objects with height and
width but without the change in perspective that would be added by depth.
IT8
Industry standard colour reference target used to calibrate input and
output devices.
Italic
A type style in which the characters are slanted upward to the right.
Usually, italic characters have different shapes than their Roman counterparts.
ITC
This is the abreviation for International Typographic Corporation, which
licenses many of the typefaces used in computerized graphic design. ITC
fonts are identical to the typefaces used on phototypesetting equipment
and based on the original "hot type" font designs. They are
considered higher quality typographic forms because they have retained
their letterform integrity through the years and are more reliable when
transferred from computer to outputting devices.
J
Jaggies
The stepstepped effect of bit-mapped type and graphics caused when square
pixels represent diagonal or curved lines. See anti-aliasing.
Jitter
Small vibrations or fluctuations in a displayed image caused by irregularities
in the display signal.
Job
In prepress and printing, the collection of files associated with a single
project including page layout files, image files, etc.
JPEG
Joint Photographic Experts Group. An organization that has defined various
file compression techniques. An image compression standard describing
a type of compression used on photographic images. JPEG compression discards
data, but does it in an intelligent fashion that results in a much smaller
file size with very little loss in quality. JPEG is also used to refer
to files that have been compressed using the JPEG standard.
Jumpline
A line of text that indicates the page where an article or story continues
or the carryover line on the subsequent page that identifies the article
or story being continued. When an article is continued from one page to
another, the jumpline placed at the end of the first page to identify
where the article is continued. A jumpline should also appear at the beginning
of the continuation page to tell the reader where the article started.
Justified
Lines of type in a column that are flush with both the right and left
column margins. If only one side of the text column is flush, it is said
to be right-justified or left-justified. Left-justified column are also
called ragged-right because the right side which is not justified tends
to be uneven. When type is justified to both the right and left margins,
wordspacing and letterspacing must be varied to allow such alignment.
K
Kern
To selectively adjust the space between character pairs to improve readability
or to achieve balanced, proportional type. Refer to kerning
Kernel size
The number of pixels sampled as a unit during image manipulation and sharpening
processes.
Kerning
Kerning refers to improving the appearance of type by adjusting the spacing
between selected pairs of letters. The most problematic pairs of letters
are AV, AY, FA, AW, PA, and AT. Kerning more important in large type and
all uppercase text.
Kerning pair
A pair of characters for which correct kerning is automatically applied.
Kerning pairs are defined in kerning tables built into most fonts.
Kerning table
A table built into most fonts containing kerning pairs.
Keyboarding
Keyboarding is the process of typing in the raw text (headlines, subheads
and body copy) for a publication in preparation for turning it over to
a graphic designer. The most commonly used program for keyboarding is
MS Word.
Keyline
A thin border or frame surrounding a colour area. A thin border around
a picture or a box indicating where to place pictures. In digital files,
the keylines are often vector objects while photographs are usually bitmap
images.
Kicker
A kicker is a short phrase or key word which introduces a headline. Kickers
can also be used to relate a headline to a particular portion of a publication.
Kiss fit
A condition that exists when abutting colours in a knockout come together
with no trapping, framing, or keylines, also known as a net fit.
Knockout
The process of removing the portion of a background colour that lies underneath
an object so that the object colour will not mix with the background colour
during printing. A printing technique that prints overlapping objects
without mixing inks. The ink for the underlying element does not print
(knocks out) in the area where the objects overlap. Opposite of overprinting.
Kraft
Extremely strong paper used when durability is important. May be unbleached
and brown like a grocery bag, bleached, or bleached and dyed.
L
Laser printer
Although a number of devices employ laser technology to print images,
this normally refers to printers which use dry toner and the xerographic
printing process.
Lay
The position of print on a sheet of paper.
Layout
The overall plan or design of a document or document page.
Leader
A leader is a repeating symbol used in combination with tab stops to draw
a reader from one area of line of text to another area. Dotted and dashed
lines are the most common leader elements.
Leading
Leading is the vertical space relationship between one line of type and
the next. Computer graphics normally default to +2 points of leading for
any given point size selected. (i.e. 10 point type uses 12 points of leading
and 14 point type uses 16 points of leading). In general, the larger a
point size gets, the better it will look with reduced leading. Increased
and decreased leading can also be used for copyfitting purposes. This
spacing was originally achieved with lead type by placing slugs of lead
between lines of type.Pronounced Ledding.
Leaf
Page with printing on both sides.
Left-justified
A paragraph of text in which the left edge is flush and the right edge
is ragged. Also called ragged right.
Letterspacing
The space between characters.
Lexicon
The words of a language and their definitions.
Ligature
In typography, two or more letters merged or tied into one.
Lightness
An attribute of object colour where the object reflects or transmits more
of the incident light.
Linear fill
A gradient fill that is projected from one point to another in a straight
line (as apposed to a radiant fill where the gradient is projected from
the center outward in a concentric manner.
Line art
An image that contains only black and white with no shades of gray. Some
examples of line art are type matter, solid black and white logos and
pen-and-ink drawings.
Linespacing
Typographic term for the distance from baseline to baseline of lines of
text.
Lint
Particles of paper dust which can degrade print quality.
Lithography
Printing process which originally utilized the oil repellant properties
of water and the water repellant properties of oil to separate the printing
and non-printing areas of an image. Subsequently, waterless lithography
has been developed, where physical properties of the printing plates are
used to repel ink in the non-printing areas and attract ink in the printing
areas.
Live Area
A page's live area is the part between borders and margins where most
text and graphics will appear.
Live Art Files
The original electronic file used to create and identify an EPS or TIFF
image. This can be an original drawing that has been created in FreeHand,
Illustrator or CorelDraw or a scanned image. Live art files are necessary
inclusions in processing electronic documents because they are the links
needed to produce high resolution output.
Logo
A logo is a stylized name of a company or organization set in a unique
way and often accompanied by an illustration or icon. A successful logo
should be reproducible in its original colour design and a black and white
version.
Lossy
Image compression that functions by removing minor tonal and/or colour
variations, causing visible loss of detail at high compression ratios.
Lowercase
Noncapital letters, such as a, b, c, and so on. The name is derived from
the practice of placing these letters in the bottom (lower) case of a
pair of type cases. Compare uppercase.
Low key
A dark image that is intentionally lacking in highlight detail.
Low resolution
An image or screen in relatively coarse detail. In raster-oriented printing
or displays, low resolution has to do with the number of pixels or dots
used to reproduce the image. The fewer the pixels per inch, the lower
the resolution.
LPI
Lines per inch - The imperial unit in which haltone frequency is measured.
Lpcm or per centimeter is the metric equivalent
Luminance
The apparent brightness/darkness of an image adjusted to account for the
inherent tendencies of the human eye to perceive some colour values as
being brighter than others despite their similar rates of light transmission
and reflection.
LZW
The Lempel-Ziv-Welch image compression technique.
M
Margin
The distance from the edge of the paper to the image area occupied by
text and/or graphics.
Mask
An analog or digital image used to eliminate unwanted portions of an image.
An analog mask could consist of a negative film, hand cut ruby or amber
film or simply photographically opaque paper. Digital mask files utilize
a clipping path and are superimposed over an image to define which portions
of the image should print and which should not. Image pixels inside the
clipping path print; pixels outside the clipping path do not. A similar
mask can be used to control the area of a graphic affected by such operations
as colour correction, filters, tool effects, etc.
Master
Artwork used as an original from which subsequent reproductions are made.
Master page
A nonprinting page in certain page layout programs that help to define
the basic layout and format of subsequent document pages. A master page
can contain headers, footers, page numbers, graphic elements, etc.
Masthead
The list of staff, owners, and subscription information for a periodical.
Matte
Not glossy, such as a matte varnish or a matte laminant.
Mechanical
In traditional publishing, one or more artboards with type galleys, line
art, "for-position-only" photostats, and tissue overlays to
indicate colour. In electronic publishing, the final camera-ready page
with position-only stats keyed to flat art to be stripped in by the printer.
Midtones
Those parts of an image with colours of intermediate value--that is, in
the 25% to 75% value range.
Misregistration
The unwanted result of incorrectly aligned colours on a finished printed
piece. Misregistration can be caused by many factors, including paper
stretch and improper plate alignment. Registration tolerances vary according
to the device on which an image is printed, but no device is capable of
consistently producing perfect registration. Trapping (choking or spreading
images that require tight registration) can compensate for misregistration.
Imaging plates directly on the press eliminates the problem of plate misalignment.
Mockup
A proof used to ensure the correct page numbers, orientation, and dimensions
are used in the final printout of an imposition layout. A good mockup
is as close as possible to the finished product, and is of great value
in showing trimming, folding and assembling in pieces involving complicated
finishing operations, such as boxes.
Moirè pattern
Interference caused by incorrect halftone screen angles which results
in an undesirable pattern in multi-colour printing. Images such as plaid
or checkered fabrics can also interfere with the angles of the halftone
screens. One advantage of stochastic screening is the reduction of obvious
and subtle moirè patterns
Monochromatic
The colour attributes of an image made up of one or more tones of one
hue.
Monospacing
Character spacing that is the same for all characters regardless of their
shape or width (such as typewriter spacing).
Montage
The process of making a composite picture by bringing together into a
single composition a number of different pictures or parts of pictures
and arranging these to form a blended whole.
Mottling
A texture similar to orange peel sometimes caused by sharpening. It is
particularly visible in flat areas such as sky or skin.
Multichannel image
An digital image where the components of the image are spread over more
than one digital channel. Refer to alpha channel.
Mylar
A polyester film product developed by DuPont often used as the base for
magnetically coated storage media.
N
Nameplate
The typographic design of a publication's name as it appears on the cover
of a publication. also called a masthead) A nameplate is the distinctive
portion of the front of any publication which usually contains the "name"
of the publication, a logo, date and volume information and remains consistent
in style from one issue to the next.
NCR paper
No carbon required paper. A special type of paper used for multi-copy
forms. NCR paper is coated with special coatings that combine under the
pressure of a writing implement to produce an image where the pressure
is applied (the first sheet of a 3 part NCR form would be coated on the
back, the second sheet coated front and back, and the third sheet coated
front). This paper comes in standard colour sequences for 2 part, 3 part,
4 part and 5 part forms. Forms are commonly padded at the head(glued at
the top) in sets
Negative leading
A type specification in which there is less space from baseline to baseline
than the size of the type itself (for example 40-point type with 38-point
leading).
Negative letterspacing
A type specification in which the space between characters is reduced
beyond the default setting either by kerning or tracking.
Neutral density
A measurement of the lightness or darkness of a colour without reference
to its hue or chroma. A neutral density of zero (0.00) is the lightest
value possible and is equivalent to pure white; 3.294 is roughly equivalent
to 100% of each of the CMYK components.
Neutralized colour
Any hue dulled by the addition of white, gray, black, or some of the complimentary
colour.
Newsprint
A coarse, absorbent, low-grade paper used for printing newspapers.
Noise
In the scanning context, this refers to random, incorrectly read pixel
values, normally due to electrical interference or device instability.
In an image, pixels with randomly distributed colour values. Adobe Photoshop
provides filters to apply noise to an image.
Nonbreaking space
In typesetting, a special space character placed between two words to
keep the words from being separated by a line break.
Nonimpact printer
Any printer that makes marks on the paper without striking it mechanically.
The most common nonimpact printers are ink-jet, thermal, and laser.
Non-lossy
Image compression without loss of quality.
O
Object
In graphics, a distinct entity. In many object-oriented applications,
objects are framed by tiny square handles that enable manipulation.
Object-oriented graphics
Computer vector graphics based on the use of construction elements (graphic
primitives) such as lines, curves, circles, and squares. These construction
elements are defined mathematically rather than specifying the colour
and position of each pixel and are combined to form complex images and
text. This contrasts to bitmap images, which are composed of individual
pixels.
Oblique
A text style created by slanting a roman font to simulate italics.
OCR
Optical Character Recognition. The analysis of scanned data to recognize
characters so that these can be converted into editable text. This is
a method used to convert hard copy into text files. Because OCR depends
upon comparing scanned images to a library of defined images, the attempt
to scan faxes and other low grade documents can result in garbled text.
OCR scans are far from perfect and require subsequent editing and clean-up.
Offset
The distance of an object from some (usually standard) reference point.
Also, the transfer of ink from one surface to another. The undesirable
effect produced when the pressure from cutting a printed job before the
ink is dry caused the ink from the front of one sheet to transfer to the
back of the sheet above it.
Offset lithography
The most common commercial, high-volume, ink-based printing process, in
which ink adhering to image areas of a lithographic plate is transferred
(offset) to a blanket cylinder before being applied to paper or other
substrate.
Oldstyle numerals
Numerals positioned so that the body sits on the baseline, creating ascenders
and descenders.
One-up, two-up, etc.
The number of identical images on a press sheet. Multiples of the same
image are often run on the same press sheet to shorten the press time
required to produce a job. This results in savings to the customer. When
a job is quoted, it is planned to print on the most economical cut of
the paper with the most economical number of multiple images possible
on that cut. Multiples of different images placed on a press sheet are
described on x-on. For example, two business cards, each having a different
name, but running on the same press sheet would be described as one-up,
two-on, while two business cards, each having the same name, would be
described as two-up.
Opacity/opaque
A material characteristic that prevents or restricts the transmission
of light. Opacity also refers to the apparent transparency (or lack thereof)
of a digital image (such as a layer) in a graphics program.
OPI
Open Prepress Interface. A set of PostScript language comments defining
and specifying the placement of high-resolution images in PostScript files
on an electronic page layout. A process used on desktop prepress systems
where high resolution scans are made and specially linked low resolution
images are used for placement in the layout. The linked low-res images
are automatically swapped with the high-res images when the file is processed
by the raster image processor. (Similar to APR.)
Optical resolution
In a scanner, a measurement of the amount of data captured for a given
area of the scanned image, typically expressed in dots per inch (DPI).
It's important to note that the optical resolution refers to the true
resolution of the scanner (usually 300 or 600 dpi for desktop models).
When a scanner claims to be able to scan "up to" 2400 or 3600
dpi, this additional resolution is accomplished via software calculations,
and is known as interpolated resolution. Refer to Resolution.
Orphan
The first line of a paragraph that falls at the bottom of a text column
and is separated from the remainder of the paragraph by a page or column
break. Also, the last line of a paragraph that falls at the top of a text
column and is separated from the remainder of the paragraph by a page
or column break. Compare widow. When a single word or line of type is
left at the bottom of a column which is continued on another page it is
an orphan.
Outline
The vector information that decribes the shape of a letter. Converting
fonts to outlines in Adobe Illustrator converts the letters to vector
outlines and preserves the letter shapes even if the computer opening
the file does not have the originating fonts installed. In the field of
graphic design, this is standard practice in preparing a file to be transferred
from one computer to another.
Outline font
A font stored in a computer or printer as a set of templates from which
the font characters, at various sizes, can be drawn.
Out-of-register
Refer to misregistration.
Output device
Any hardware equipment, such as a laser printer or imagesetter, that images
computer-generated text or graphics onto a substrate, such as film or
paper.
Outside margin
In a book or magazine, the space between the fore-edge (the edge opposite
the spine) trim and the text.
Overline
A font style in which a horizontal line appears above characters. Also,
a brief tag line over a headline that categorizes the story.
Overprint
The opposite of knockout. A printing technique in which all overlapping
inks print on top of each other, and transparent inks blend to form a
new colour. See also knockout, trapping.
P
Page break
The point at which the flow of text in a document moves to the top of
a new page.
Page-description language
A programming language, such as PostScript, that is used to describe output
to a printer or display device.
Pages per minute (PPM)
A rating of printer output, especially used with laser printers.
Pagination
The process of dividing a document into pages for printing and/or of adding
page numbers to the header or footer of each page.
Palette
A subset of the colour lookup table which establishes the number of colours
that can be displayed on the screen at a particular time. Also a user-defined
set of colours used in a graphics program.
Pan
To scan horizontally or vertically to bring off-screen portions of a display
or image into view.
Pantone Matching System (PMS)
The most common colour matching system used by commercial printers for
spot colour printing. The pantone matching system is comprised of ink
formulas for mixing colours by weight using a standard set of basic colours.
Swatch books with over 500 numbered colours allow the customer to specify
the desired colour exactly, and allows the printer to maintain the same
colour from press run to press run.
Paper
A thin, flexible material made from a pulp prepared from rags, wood, or
other fibrous material, and used for writing or printing on, for packaging,
as structural material, and so on.
Pastel colours
Colours resulting from adding white pigment to neutralized colours.
Pasteup
Traditionally, the process of assembling mechanicals by pasting galleys
and line art in place. In desktop publishing, traditional pasteup has
largely been replaced by electronic page assembly.
Path
In file storage, the route followed by the operating system to find, store,
or retrieve files on a disk. In graphics, the vector description accumulation
of line segments or curves. Vector paths can be filled, stroked, used
as masks and clipping paths and type may be made to follow or fit within
such paths.
Perspective view
A display method that shows objects in three dimensions with the depth
aspect rendered according to its perceived relative distance or position.
Phantom
See Ghost
Photo CD
A method created by Kodak for scanning and storing photographic images
on CD ROM.
Pi font
A font made up of non-standard characters such as arrows, map symbols,
bullets, and dingbats.
Pica
In typography, a unit of measurement equal to 12 points or approximately
one-sixth inch.
Picking
The pulling off of particles from a paper's surface during printing. Particles
accumulate on the plate or blanket, causing printing defects.
PICT/PICT 2
A file-format for encoding both bitmapped and object-oriented graphical
images. A format for defining images and drawings on the Macintosh platform.
PICT 2 supports 24-bit colour. Pict files are not universally supported
by printing devices, and are not recommended for graphic reproduction.
Picture window
A clear rectangle in a negative into which a halftone negative would be
stripped by the printer. This has become unnecessary because of the function
of page layout programs in combining photos and text prior to the creation
of film, plates or direct to press imaging.
Pigment
A substance, usually a powder, added to a liquid binder to give colour
to paints or inks. Some properties of pigments include lightfastness (non-permanent
pigments are know as fugitive) transparency and hue.
Pitch
A measure of fixed-width fonts that describes the number of characters
that fit in a horizontal inch. Refer to Monospacing.
Pixel
Picture element. A tiny rectangular element in the rectilinear grid of
the computer screen that is either "painted" on or off to form
an image or character. If a pixel is black-and-white, it can be encoded
with only 1 bit of information. If the pixel must represent a larger range
of colours or shades of gray, the pixel must be encoded with more bits
of information as follows 2 bits for four colours or shades of gray, 4
bits for sixteen colours or shades of gray, and so on. An image of 2 colours
is called a bitmap; an image of more than 2 colours is called a pixel
map.
Pixel map
The data structure of a colour graphic which includes the colour, resolution,
dimensions, storage information, and number of bits used to describe each
pixel. When only 1 bit per pixel is used, the data structure is called
a bitmap.
Pixel skipping
A means of reducing image resolution by simply deleting pixels throughout
the image.
Plate cylinder
Cylinder on a rotary press to which the metal printing plate is attached.
Plate
An image carrier made of polyester or aluminum used on a press. Plates
are coated with a photochemical emulsion which is exposed by a light source
in a vacuum contact frame, or by a laser in the case of computer-to-plate
or direct-to-press applications. The exposed image becomes ink receptive
and the unexposed are repels ink. During offset printing the image is
transferred from the plate to a rubber blanket which transfers the image
to the paper (the soft blanket more easily conforms to the surface of
the paper).
Platemaking
The process of exposing and developing the photochemical plate used to
transfer the image on an offset press.
Platen
The cylinder used in most impact printers and typewriters around which
the paper wraps and against which the print mechanism strikes the paper.
In letterpress printing and foiling, the surface of the press against
which the type or die presses, and which allows the transfer of the image.
PLI
A type of removable Hard disk drive. Also commonly reffered to as a Syquest
Drive No longer in common usage.
Plot
To create a graphic or a diagram by connecting points representing values
defined by their positions in relation to the x (horizontal) axis, y (vertical)
axis, and z (depth) axis.
Plotter
Any device used to draw charts, diagrams, and other line-based graphics.
PMS
(Pantone Matching System) A commonly used system for identifying specific
ink colours. The North American printing industry standard for defining
non-process colours. Refer to Pantone Matching System.
PMT
Acronym for photomechanical transfer. PMTs are created by exposing a photosensitive
paper image carrier through a negative, positive or on a camera; sandwiching
this carrier with a receptor paper and processing the sandwich through
a special processor. The latent, unstable image on the carrier is transferred
to the receiver paper which results in a high quality, stable line or
halftone image. Prior to the advent of page layout programs and imagesetters,
images were commonly made into PMTs for paste-up purposes.
Point
A typographical unit of measure equal to approximately 1/72 inch, often
used to indicate the height of type characters or the amount of space
between lines of text (leading). There are 12 points in a pica.
Polygon
Any two-dimensional closed shape consisting of three or more sides. Triangles,
rectangles, hexagons, octagons, etc. are all polygons.
Polyline
A line consisting of two or more connected segments.
Portrait mode
A page orientation in which the horizontal dimension of the image follows
the narrower dimension of a rectangular page.
Portrait monitor
A computer display with a shape higher than it is wide, used to display
an 8.5-by-11-inch page at full size in portrait mode.
Posterize
To limit all the values in an continuous tone image to some smaller number,
resulting in the conversion of continuous tone data into a series of visible
tonal steps or bands.
PostScript
A page-description language from Adobe Systems that offers flexible font
capability and high-quality graphics. PostScript is the copyrighted term
for Page Description Language owned by the Adobe Corporation. PostScript
defines images as vector (outline) information permitting extreme flexibility
in scaling, colour, shading, position, rotation, etc.
PostScript Printer Description file
See PPD.
PPD
Acronym for PostScript Printer Description, a file format developed by
Adobe Systems, Inc., that contains information enabling application software
to optimize PostScript printing by utilizing the printer properties described
for each type of designated printer.
PPI
Pixels per Inch. Units of measurement for bitmapped or pixel mapped images.
The number of pixels in a linear inch (as opposed to a square inch). Therefore,
a 72-ppi monitor displays 72 pixels per linear inch, or 5,184 (72 x 72)
pixels per square inch. PPI is technically the correct terminology for
describing image and monitor resolution, as apposed to DPI
PPM
Pages per minute. A rating of printer output, especially used with laser
printers.
Preflighting
Evaluating an electronic file before sending it to an imagesetter, platesetter,
large format printer, direct-to-press or any other reproduction device,
specifically for the purpose of detecting and correcting any problems
that would render the resulting film, plates, or large format prints or
press sheets unusable. A typical preflight check would involve ensuring
that all linked images and fonts are supplied, that all information needed
for output is available, that images destined for process colour printing
are CMYK, not RGB, that image file formats are supported and are high
resolution, that trapping has been applied where necessary and only the
desired colours have been applied to images. Preflighting a job is a chargeable
service designed to save the customer money by preventing wasted materials
and labour due to deficiencies in customer supplied files.
Prepress
Any of the operations required to prepare a digital file, or mechanical
artwork for printing, including the production of plates or the transfer
of files to the imaging device in computer-to-plate or direct-to-press
processes.
Prepress service provider
In the publishing industry, the generic term for colour separation houses,
commercial printers, electronic prepress houses, service bureaus, and
in-plant printers or any company that provides prepress operations. Refer
to prepress.
Press Proof
A proof actually run on a press, using the printing inks and substrates
as specified for the finished job. Because the printer must keep the job
on the press while the customer examines the press proof for approval,
customers are generally charged press time until the approval is received.
This can be a very expensive proofing method, and is discouraged, except
when the cost is justified in the case of an extremely prestigious job.
Press sheet
In sheet-fed printing, the printed sheet of paper that comes off the press.
Primary colour
The hues from which other colours can be mixed. The additive primaries
(for projected light) are red, green, and blue. When added together, these
hues form white light. The standard pigment primaries are red, yellow
and blue. The subtractive four colour process primaries are cyan, magenta,
and yellow and black.
Primitive
A shape, such as a line, curve, circle, or polygon, that can be drawn,
stored, or manipulated as a discrete entity by a graphics program.
Print buffer
An area of memory to which print output can be sent for temporary storage
until the printer is ready to handle it. A print buffer can be located
in a computer's random-access memory, in the printer, on a disk, or in
a special memory unit between the computer and the printer. Refer to Print
Spooler.
Printer
A computer peripheral that puts computer-generated text and images on
paper or other medium.
Printer controller
The processing hardware in a printer, including the raster image processor,
the memory, and the microprocessor.
Printer engine
The portion of a printer that performs the actual printing. Many printer
engines are self-contained units that are easily replaced.
Printer font
A font residing in or intended for a printer. Printer fonts differ from
screen fonts which are intended for displaying characters on a computer
screen. Also known as Type 1 Fonts or Outline Fonts, are Postscript language
programs that mathematically describe the appearance of each character
in a font, using lines and curves. Printer fonts generate smooth output
on-screen and on a postscript printer at any size. You must have a printer
font installed for any typeface you print. This category can include TrueType
fonts, as well as Postscript fonts.
Printer's marks
The marks printed on a press sheet or film to aid in positioning the print
area on the press sheet, checking the quality of the printed image, and
trimming the final pages. Printer's marks may include calibration bars,
crop marks, and registration marks.
Printer spread
A pair of pages positioned across a fold from each other on the press
sheet. The pages in a printer spread are positioned so that when the final
press sheets are collated and folded, the pages will be in the proper
order, as apposed to reader spreads, which have consecutive pages on the
same sheet to simplify proofreading. Beware of setting up a saddle-stitched
document in reader spreads, unless you plan to convert it to printer spreads
prior to submitting to a printer. Some programs do not allow linked documents
to easily be converted to printer spreads so it can be expensive for the
printer to spend the extra time to impose the pages properly for printing.
Process colours
The four transparent inks (cyan, magenta, yellow, and black) used in four-colour
process printing. See also Colour separation.
Print head
The part of a printer that mechanically controls the imprinting of characters
on paper. The print head can consist of pins that strike a ribbon, ink
jets, or pins that pass an electrostatic charge to the paper.
Printing plates
The metallic or polyester sheets, usually imaged from film negatives or
directly from a digital file, used to transfer ink to paper (actually,
to the printing blanket) on a commercial printing press. One plate is
required for each colour being printed.
Print job
Any number of characters, images, pages, or documents sent to a printer
as a single unit.
Print quality
The clarity of printer output, partly determined by resolution, but subject
to many factors such as moisture content of the paper, screen frequency
designated in the print file, etc.
Print server
A computer dedicated to managing a network printer.
Print spooler
Software that intercepts a print job on its way to the printer and sends
it to a disk or memory where it can be held until the printer is ready
to process it.
Process colour
Any one of the subtractive primary colours (cyan, magenta, yellow or black).
Process colour may also refer to the technique of creating full colour
images by blending percentages of cyan, magenta, yellow, and black inks.
See also spot colour.
Processing
Manipulating data within a computer system. In a RIP system, processing
means rasterizing the data and outputting it to film or other medium.
Profile
The colour characteristics of an input or output device, used by a colour
management system to enhance colour fildelity.
Proof
A reasonably accurate representation of how a finished page is intended
to look. Proofs can be in black and white or colour.
Page
One side of a leaf of a book, magazine, newspaper, letter, and so on.
Proofread
To check typeset material for spelling, punctuation, and basic document
layout (alignment of elements, etc.).
Proportional font
A set of characters with a variable amount of horizontal space allotted
to each. For example, the letter i has less space allotted to it than
the letter w.
Proportional spacing
A type of character spacing in which the horizontal space each character
occupies is proportional to the width of the character.
Pull quote
A sentence or phrase excerpted from the body copy and set in large type,
used to break up running text and draw the reader's attention to the page.
Also known as a blurb, breakout, or callout. Pull-quotes (also called
out-quotes) are short phrases or sentences taken from body copy and emphasized
by enlargement, boxing, or colour background to highlight surrounding
content.
Pulp
Beaten and refined vegetable fibers (cellulose) to which chemicals and
fillers are added, used to make paper.
Q
Quality factor
A multiplication factor applied to output screen ruling to calculate scanning
resolution for optimum output quality. Refer to halftoning factor.
Quarter tone
Tonal value of dot, located approximately halfway between highlight and
midtone. Tones between shadow and midtones are known as 3/4 tones and
those between highlight and midtones are known as 1/4 tones.
Quantity
Any number (positive or negative, whole or fractional) used to indicate
a value.
Queue
A stored arrangement of computer data or programs, waiting to be processed
(usually in the order in which they were received).