Image-specific set of colors chosen to most closely represent those in the original
source. Part of a custom color look-up table.
Red, Green, and Blue are referred to as additive colors. Red+Green+Blue=White.
Adobe Systems, Inc:
A software applications company located in Mountain View, CA, known for
Photoshop, TypeManager and Illustrator.
The specific process in a computer program used to solve a particular problem.
An effect caused by sampling an image (or signal) at too low a rate. It makes rapid change
(high texture) areas of an image appear as a slow change in the sample image. Once
aliasing occurs, there is no way to accurately reproduce the original image from the
An additional 8bit channel, used by some editing software for masking or additional
The process of reducing stair-stepping by smoothing edges where individual pixels are
The Local Area Networking system introduced by Apple Computer.
The basic design of a computer system, its circuitry, microprocessor, memory, etc.,
and its connectivity of components.
Long-term storage of data or images. Archiving is generally accomplished on some form of
magnetic media; such as disk or tape, or optical media; such as Writable CD.
Information from a JPEG image that is misinterpreted. color faults that visibly show up in
A digital camera that uses a large CCD chip (an array of rows and columns of light
sensitive pixels) to sense the entire image at one time as opposed to scanning the image
one row of pixels at a time.
A portion of large computer system that assists processing data fast. Several
Visual effects introduced into a digital image in the course of scanning or
compression that do not correspond to the image scanned.
The use of computers to solve problems the way human being does.
An acronym for the American Standard Code for information Interchange, which converts
keyboard input into digital information. It covers all the printable and control
characters with a system consisting of 128 seven-bit patterns for printable characters
In computer graphics, the images' relationship of width to height must be kept the
same when it is displayed on several screens.
Adobe utility program that improves a computer monitor's display of type at any size.
A Generic term used to deal with animation, audio and video.
Concurrent processing work performed by the computer to carry out the investigative
instructions of the operator while other activities are being performed.
An artifact of color gradation in computer imaging, when graduated colors break into
larger blocks of a single color, reducing the "smooth" look of a proper
The transmission capacity of a communications channel, usually expressed in bits or bytes
per second (the former is also called baud rate).
Image distortion that spread the center dimensions of the image.
The Photo-CD image resolution [512x768 pixels] formatted to be displayed on TV.
The 1536 x 1024 pixels image ideal for high definition TV.
The 2048 x 3072 pixels image suitable for digital Imaging.
Max resolution for Photo-CD The 4000 x 6000 pixels image produces a 72 MB image File.
A Method that allows for repetitive processing of groups of data by executing only one
The speed at which computer data can be transmitted via modem. Example: Modem rates
may be 1200, 2400 and 9600 baud. To determine the number of bytes transferred per second -
divide the baud rate by 8.
Bulletin Board System, a system that allows Computer 2 computer communication via
modem to exchange and copy files.
A mathematically defined curve made up of four points, two ends and two in between,
that affect its shape.
A Matrix for comparison of central pixels to surrounding pixels.
A coding or counting system with only two symbols or conditions (off/on, zero/one,
mark/space, high/low). The binary system is the basis for storing data in computers.
A binary digit, a fundamental digital quantity representing either 1 or 0 (on or off).
The amount of tone data per sample expressed in number of bits. Typical bit depths are
1 for line art, 8 for grayscale and 24 for color images. If the number given for bit depth
is greater than 16 and is not divisible by 3 then it is probably referring to 4 channel
An image made up of dots, or pixels. Refers to a raster image, in which the image consists
of rows or pixels rather than vector coordinates.
Stair-stepping of shades in a gradient or on the blend.
When a picture extends to the extreme edge of a page it is said to bleed. A full page
bleed has an image covering the entire page with no borders. In order to give the printer
some leeway in trimming a page with a bleed image you need to provide an image that
extends beyond the crop marks. This extra area is called bleed and is usually 1/8 or 1/4
Beyond the cutting-edge of technology. A company that is accustomed to working in the
experimental fringes out beyond the cutting-edge is very capable of producing work that is
The art of softening the detail of a digital image. The process can be applied
selectively to portions of an image.
Automatically locating the correct edge of an image on a scan so that marking from the
edge, frame, etc. is not captured.
The value of a pixel in an electronic image, representing its lightness value from black
to white. Usually defined as brightness levels ranging in value from 0 (black) to 255
See Ink Jet
A special area set aside either in hardware or software for temporary. Usually, the bigger
the buffer, the faster the computer can process other data.
Combining two or more different functions into one expansion board or peripheral device.
Also combining software "bundled" with hardware.
An ensemble of eight bits of memory in a computer.
A temporary storage area for information which locates itself between the hard disk and
the RAM by employing intuitive logic. It also speeds up the access time of the data.
The act of adjusting the color of one device relative to another, such as a monitor to
a printer, or a scanner to a film recorder. Or, it may be the process of adjusting the
color of one device to some established standard.
The entire image displayed on the monitor, but not necessarily at full resolution.
A digital camera is said to Capture an image rather than Take a picture.
Charged-Coupled Device. A light sensitive electronic device that emits an electrical
signal proportional to the amount of light striking it. Used in scanners and video
A device that mounts many CCDs together to allow for capture of many pixels at the
Compact Disc-Read Only Memory. A CD-ROM drive uses the CD (compact disc) format as a
computer storage medium. One CD can store 640 megabytes of data and other mixed media on a
disc about the size of a traditional 5-1/4-in. floppy disk.
Compact Disc Recordable writes data to discs, which can then be read by standard CD-ROM
Computer Graphics Metafile. An image file format designed to handle a wide range of image
types, but currently used primarily for vector graphics.
The process of building a Look-Up-Table (LUT) for a calibrated monitor. By profiling the
output of numerous key colors from a monitor a LUT can be created that allows the computer
to substitute corrected (Characterized) colors to achieve consistent and accurate output.
CIE (Commission International l'Eclairage):
An international standard committee that defined the de facto standard color model
used in all color management systems.
A systems architecture design that divides functions (which might be part of a single
application) between two or more computers. The client is the machine that requests
information; the server is the machine that supplies it. A typical client/server
architecture for imaging might allow a server to store and transmit a compressed file, and
the client to decompress, process, and display the image.
Vector defined outlines used to silhouette an object. They are created from ``Bezier"
curves and are ideally suited in describing the hard edge outlines of mechanical or
man-made objects. A clipping path is a particular type of path that instructs the RIP to
ignore any part of the image outside of the path. If you want to place a file over another
object or background in a page layout program such as Quark-Xpress then you will have to
use a clipping path to eliminate the white that surrounds the image.
Color Lookup Tables - A color referencing system
Color Management System.
A comprehensive hardware/software solution of maintaining color fidelity of an image from
scanner to monitor to printer.
CMY (Cyan, Magenta, Yellow):
The three subtractive color primaries.
CMYK (Cyan, Magenta, Yellow, Black):
One of several color encoding system used by printers for combining primary colors to
produce a full-color image. In CMYK, colors are expressed by the "subtractive
primaries" (cyan, magenta, yellow) and black. Black is called "K" or
keyline since black, keylined text appears on this layer.
The effect of one color dominating the overall look of an image. Often caused by
improper exposure, wrong film type, or unusual lighting conditions when shooting the
original image. Also caused, when scanning, by the sometimes unpredictable interaction
between an image and a scanner.
A mechanism for controlling color changes, and matching colors. Color curves are set
by user-adjustable lookup tables that define a color transform, which may be applied to
each primary additive or subtractive color in the image.
Any color medium representing its own range of color, including film, a monitor,
printed images or the human eye.
Proofs may be in-house for checking composition, or a representation of the final
print for client OK. Common types are CromalinTM, MatchPrintTM, inkjet, dye sublimation
and laser copies.
An image that has been converted or "separated" from RGB into the four
process colors. See CMYK.
There are numerous methods of creating or describing a specific color and tone. These
different models are called Colorspaces. examples are RGB, CMYK, LAB, YCC.
A term for combining images, artwork, lineart and type.
The reduction of data to reduce file size for storage. Compression can be
"lossy" (such as JPEG) or "lossless" (such as TIFF LZW). Greater
reduction is possible with lossy compression than with lossless schemes.
Continuous tone images use pixels instead of halftone dots. That is to say that rather
than simulating variations in tone by increasing or decreasing the size of closely spaced
spots of 100% ink or pigment color a continuous tone (CT) image is able to print or
display continuously varying levels of pigment. To achieve the perception of a smooth
(continuous) tonal transition from black to white it is necessary to have 256
differentiations of tone from black to white. If you have significantly fewer
differentiations the human eye will begin to perceive breaks between the tones which will
result in posterization and banding in the gradients.
A measure of rate of change of brightness in an image. ---HIGH contrast implies dark
black and bright white content; ---MEDIUM contrast implies a good spread from black to
white; ---LOW contrast implies a small spread of values from black to white. Crop: To
permanently discard unwanted information in the perimeter area of an image.
A proof the printer promises to be able to match on press.(See: Matchprint)
CPU/ Central Processing Unit:
A large chip which holds the "brains" of the computer.
Digital Audio Tape format is a mini tape format for image storage and backup.
The process of returning a compressed file to the full file size.
The setting in a computer program which will take effect if no changes are made.
The measure of light blocking (in the case of transparencies) or absorption (in the
case of prints), expressed logarithmically. Typical slides have a density of 3.0 while
typical prints have a density of 2.0.
Desktop refers to computer and imaging systems linked to personal computers (PC's) such as
Apple Macintosh or Intel Pentium computers as opposed to larger workstation type of
computers such SUN or Silicon Graphics. Desktop systems use operating systems such as
Macintosh OS, or Windows 95. Workstation systems typically use UNIX or Windows NT
Data Interchange Format, a standard for access between programs.
A system or device in which information is stored or manipulated by on/off impulses,
so that each piece of information has an exact or repeatable value (code).
A camera that directly captures a digital image without the use of film.
Improves performance of disk controller via high-speed memory.
Camera displacements are a feature of Large Format studio cameras that allow the
relationship between the film plane and the lens plane to be altered in order to alter and
control the perspective of the image. By using displacements it is possible, for example,
to look up at a building and keep the vertical sides of the building parallel without
having the keystone effect normally experienced with a camera. Digital cameras do not work
well with significant displacements. The control of perspective is often best left to be
accomplished in Photoshop
Changing the size of an image in a non-proportional manner. Also known as "anamorphic
scaling." Dither - The process of adding dots to a small area in order to smooth out
the appearance of an image, or specifying colors to adjacent pixels in order to simulate
intermediate colors in a bit mapped image.
A technique of using patterns of dots or pixels to create the effects of an intermediate
tonal value. When a monitor cannot display intermediate colors or tones it attempts to
achieve the required color by intermixing the two closest colors in a scattering
(dithering) of pixels. This occurs most often when you attempt to display a full color
image on a monitor with a 256 or a 64,000 color video display board. In an illustration
dithering can make typography almost impossible to read.
Strictly speaking a dot is the smallest spot an imagesetter, or printer can output and is
usually expressed in dots per inch (dpi). However the term dot is often used
interchangeably with Pixels (ppi) or Halftone Cells (lpi or L/S). An imagesetter dot is of
a specific and unvarying size. A 300dpi laser printer can only make dots that are 1/300 of
an inch in diameter. To make a bigger spot it uses several dots. On the other hand, a
halftone dot varies in size in order to simulate continuous tone. (see: Halftone)
The effect of ink spread and absorption into paper during printing resulting in darker
tones, especially midtones.
The transfer of information from one computer to another. Frequently used to describe
file transfer from a network file server to a personal computer.
DPI (Dots Per Inch):
The measurement of resolution of a printer or video monitor based on dot density. For
example, most laser printers have a resolution of 300 to 600 dpi, most monitors 72 dpi,
most PostScript imagesetters 1200 to 2450 dpi. The measurement can also relate to pixels
in an input file, or line screen dots (halftone screen) in a prepress output film.
Dynamic Random Access Memory - a computer memory device offering high data packing density
and data rates. Also Dram chips for PCs.
A software utility designed to tell a computer how to operate an external device. For
instance, to operate a printer or a scanner, a computer will need a specific driver.
A graphic art effect designed to simulate the shadow cast by three dimensional shapes
A high-end scanning device, utilizing PMT technology, used to digitize prints,
transparencies, and artwork.
Acronym for desktop publishing, including typesetting, image handling and page
A type of continuous tone printing process that produces a vibrant 300ppi color print. The
pixels are printed by a thermal print head that sublimates (vaporizes) the dye from a
colored saran wrap like ribbon onto the dye-sublimation paper. The hotter the element on
the thermal printing head, the darker the spot of color.
The dynamic range or Optical Density of a scanner is a measure of the range of
densities and the deepest shadow density that the scanner can see into and record
information. If the dynamic range of the transparency exceeds that of the scanner then the
scanner will perceive everything beyond its range as black. A Drum Scanner with a Dynamic
Range of 3.8D and a bit depth of 48 will produce a much higher quality, richer, more
detailed scan than a Flatbed Scan with a Dynamic Range of 2.5D and a bit depth of 24 at
the same scan resolution.
A image, or line art, in whole or part of the page, composite or file.
A halftone screen dot that can produce better tonal gradations than a circular dot.
Emboss - Usually done photo-mechanically, but some EIM & CEPS systems can accomplish
the process in seconds.
Coating on the light-sensitive material. The opposite side of the base.
Every computer works within a netware or software surrounding. The condition in which
a computer operates. Also, an operating system used to support another operating system is
Encapsulated PostScript. A subset of the PostScript page description language that
allows any single-page artwork, be it line art or image data, to be saved and placed into
any other EPS compatible document.
A networking system providing transfer of data between computer systems and
peripherals over a coaxial link.
The process of transporting data from one computer, program, type of file format, or
device to another.
The process of merging borders, or softening the edge around a mask.
Very thin cables used in transmitting data.
A named collection of binary information stored as an apparent unit on a secondary
storage medium such as a computer disk drive. Film Recorder: A device that is used to
record a digital image onto photosensitive film.
Film recorder drum:
The highest quality film recorder. They may be sheet- or roll-fed with exposure via
white light or laser. It is possible to image on negative or positive film plus
photographic print material.
An application that extends or offers unique expansion of a software program. This is a
key component of many imaging software programs.
A type of memory chip that can retain data after the system has been turned off. Its
advantage is that digital cameras with flash memory can have batteries go "dead"
and yet retain image data.
Flat Bed Scanner:
An optical scanner in which the original image remains stationary while the sensors
(usually a CCD linear array) passes over or under it. The scanned material is held flat
rather than being wrapped around a drum.
FPO (For Position Only):
A low resolution image file used for placement in page layout programs. The low-res file
is small so that it doesn't slow down the machine and is used for position only. It is
swapped out for the high resolution file when the page is RIPíed.
FTP File transfer protocol:
A method of moving or transferring files between computers on the Internet.
GIF File Format :
Stands for Graphic Interchange Format, a raster oriented graphic file format developed
by CompuServe to allow exchange of image files across multiple platforms.
GIF89 File Format:
The most recent GIF standard designed for image use on the Internet and on line services.
The measure of the contrast of an image or imaging device.
The measure of contrast that results in lightening or darkening the midtone regions of
an image. Also, the amount midtones need to be adjusted on a monitor.
The range of colors and tones a device or colorspace is capable of recording or
reproducing. The human eye can sense many more colors than can be reproduced on a computer
monitor in RGB colorspace. The human eye has a larger Gamut than the computer monitor.
A brush with variable density.
A measure of computer memory or disk space consisting of about one thousand million
bytes (a thousand megabytes). The actual value is 1,073,741,824 bytes (1024 megabytes).
Graphic Port Interface Bus - A standard interface in the graphic arts for graphic
computers and peripherals.
A smooth spread between colors.
A term used to describe an image containing shades of gray as well as black and white.
Graphical User Interface - a computer control system whereby the operator commands the
computer with a mouse or stylus.
Slang for a non-professional dedicated computer operator.
In order to simulate the reproduction of continuous tone images with ink on paper it
is necessary to convert the continuous tone image into a halftone image. Black ink is just
that...black. To print a gray tone from black we print many closely spaced black dots on
white paper. The dots are so small that the eye doesn't see them so what it does see is
the mixture of black ink dots and bare white paper between the dots which appears to be
gray. A 50% gray would have dots sized so that they covered half of the area with black
ink and left half of the area as bare paper.
In order to effectively simulate continuous tone we need to be able to reproduce 256
levels of tone between black and white. So for a halftone image we need to be able to
print 256 different sizes of dots. An imagesetter varies the size of the halftone dot by
printing clusters of much smaller dots. To print 256 different sizes of halftone dots an
image setter divides the area up into halftone cells that are 16 imagesetter dots
wide by 16 imagesetter dots high. (16x16=256) If, within the boundaries of this halftone
cell the imagesetter prints 128 black dots then you have a 50% halftone dot. So if an
image setter is capable of printing 2400 dots per inch then the highest line screen you
can output is 150 lines per inch (2400/16=150).
Refers to a print or proof, as opposed to viewing on a monitor.
High-Definition Television - Approximately double the resolution of "normal"
A vertical bar graph displaying the distribution of the tonal values of the pixels in
an image. The X axis represents the tonal value of the pixels (0-255) and the Y axis
represents the number of pixels having that tonal value.
Hewlett-Packard Graphics Language.
HTML (Hypertext Markup Language):
An encoding format for identifying and linking electronic documents used to deliver
information on the World Wide Web.
A term used to describe the entire range of colors of the spectrum; hue is the
component that determines just what color you are using. In gradients, when you use a
color model in which hue is a component, you can create rainbow effects.
File storage format used with Kodak's PhotoCD.
Output devise to image onto separation film. They are the preferred PostScript
compatible and non-PostScript devices.
Electronic representation of a document, stored and displayed as a bitmap.
Capturing and manipulating images in order to enhance or extract information. Image
Resolution: The number of pixels per unit length of image. For example, pixels per inch,
pixels per millimeter, or pixels wide.
Term used to describe both the products and industry dealing with images.
The process of bringing data into a document from another computer, program, type of
file format, or device.
A type of color file that uses only one channel and assigns one of 256 colors to a pixel.
Sort of like Paint-by-Numbers approach to color. The quality is poor...but the files are
really small...good for the web.
An inexpensive alternative to a laser printer, an ink-jet printer forms text and
images out of dots created by jets of ink. Color ink-jets support many different media
sizes and output resolutions.
The technique of estimating the tonal value that lies between two known tone samples.
Used for enlarging an existing image. Also used when capturing an image during the
scanning process to achieve higher than optical resolution.
Iris printers are extremely sophisticated Ink Jet Printers that spit out droplets of ink
that are as small as red blood cells! (1/2000 of an inch) Iris printers are very popular
not only as proofing devices but also for making fine arts quality limited editions on
specialized papers such as heavy water color stock. These are often called Geclee prints
A 16-bit bus for PCs.
Another word for stair-stepping or staircased edges of a raster or vector image. This
problem can appear when low-resolution files are blown up to large sizes.Jaggies:
A file compression standard established by the Joint Photographic Experts Group that
uses a combination of DCT and Huffman encoding to compress images. JPEG is a
"lossy" compression algorithm, meaning that it slightly degrades image quality.
An amount of computer memory, disk space, or document size consisting of approximately
one thousand bytes. Actual value is 1024 bytes.
Kodak Approval Proof:
A digital proofing method that accurately simulates a halftone proof from a digital file
without having to make halftone separation films.
LAN (Local Area Network):
A communications network that's physically connected by cables and confined to a
single office or a single building. It enables a group of computers to exchange files and
share peripherals. LPI (Lines Per Inch): The frequency of horizontal and vertical lines in
a halftone screen.
A printer using laser copier technology to produce high-quality printed material from
computer data. The laser charges an electrostatically sensitive drum to accept carbon
based toners. The toner is then transferred and fused to paper or transparency material.
A LightJet printer uses Red, Green, & Blue Lasers to write a continuous tone image
onto photographic printing paper in a similar manner to a film recorder. LightJets can
produce high quality prints 48in. wide by however long.
Images comprised of only pure black-and-white data. Also a mode of capturing such
The number of halftone cells per inch expressed as lines per inch (lpi)
Loose Color proofs are proofs of individual images that have not been assembled into page
layouts. (see; Composite Color)
Reduces the size of files by creating an internal shorthand that rebuilds the data as
it originally were before the compression. Thus, it is said to be non-destructive to image
data when used.
A method of reducing image file size by throwing away unneeded data, causing a slight
degradation of image quality. JPEG is a lossy compression method.
Lines Per Inch
Lempel-Ziv-Welch. A popular, lossless image compression algorithm.
A temporary stencil restricting the action of various functions to a selected area
within the picture or page. Masks can be created by drawing points around an element or
automatically by specific density or hue values.
A Matchprint is a printers Contract Proof made from the same halftone negative film that
will be used to burn the actual offset printing plates. It is called a contract proof
because the printer promises to be able to make the printed page match the Matchprint.
Other, similar, contract proofing media are FujiPrint, PressMatch, and Cromalin Proofs.
An amount of computer memory consisting of about one million bytes. The actual value
is 1,048,576 bytes.
One Million Pixel image. Produced with higher end digital cameras.
The range of tones in an image located approximately halfway between highlights and
Multi-purpose Internet Mail Extensions. A standard for embedding multimedia data in e-mail
A device that converts digital computer data into signals for transmission over
A visible pattern that occurs when one or more halftone screens are misregistered in a
A computer Display screen. A monitor is an RGB display device
An image compression method for motion picture files.
A group of computers connected to communicate with each other, sharing resources and
An Internet discussion group devoted to a particular topic
A pattern of concentric, multi-colored rings occasionally introduced in a scanned
image by contact of transparency film with the glass platen in a scanner.
Communications interface used in Macintosh computers to transfer video data from
memory to the graphics display card.
Photoshop is the most popular Digital imaging software program. It allows for the color
correction, tonal adjustment, sizing, and cropping of digital image files. It is also
enables you to do retouching, image manipulation, compositing, and special effects.
The native bitmapped file format for Macintosh
A digital image is made up of small continuous tone spots called pixels. The word pixel is
derived from the words Picture Element. In an RGB image (with a Bit Depth of 24) each
pixel can be any one of 16.7 million colors/tones. Each pixel is made up of three color
channels (Red, Green, & Blue) and each channel can be any one of 256 levels of tone
(256 x 256 x 256 = 16,777,216)
The stair-stepped appearance of a curved line in digital imaging.
Windows Paintbrush bitmap image standard
An Offset Printing plate is a metal plate photo-etched from the halftone separation
A term taken from the motion picture industry which refers to all of the editing that
takes place after the actual shooting of film.
To achieve the impression of continuous tone we need to reproduce 256 differentiations of
tone from white to black. If we break down the tonal range into fewer differentiations you
begin to see the breaks between the individual tones. We call this posterization, it often
appears in smooth color gradients.
Postscript is a software printer description language used in typography, graphics and
page layout programs that allows vector graphics to be rasterized (RIPíed) for output on
a printer, imagesetter, or film recorder.
Pixels per Inch.
The process of preparing images, illustrations, and page layouts to be printed. Including
scanning, separations, image manipulation, retouching, imagesetting, and proofing. (See:
An ICC description of a particular imaging input or output device that allows the Color
Management Software to apply the proper color transformations to the image file to match
the specific limitations of the device.
A two-dimensional array of black and white cells, called pixels or picture elements, which
when displayed form an image or representation of an original document.
To convert vector graphic artwork into bit mapped artwork
A measurement of the amount of detail in an image file as measured in units per inch such
as dpi, ppi, or lpi: Dots per inch, Pixels per inch, or lines per inch. Sometimes
resolution is measured in units per millimeter. a ``Res 14" file would be scanned in
at 14 pixels per millimeter which would be equivalent to 355.6 ppi (14 x 25.4 = 355.6)
Red, Green, Blue; the color language of computers. Computer monitors and digital cameras
use these primary colors to create all of the colors seen on the monitor.
Raster Image Processing: to rasterize a file for output. When a page layout document such
as a Quark file is RIP'ed all of the page elements (typography, photography,
Illustrations, and Graphics) are assembled and rasterized into a Bit Mapped image to be
output. It is in the RIP that the halftone screens are applied to the artwork.
A digital camera that uses a single row of CCD sensing elements to scan the image one row
of pixels at a time.
Output Simulation Mode is a feature color management software that allows you to
accurately simulate on the monitor display what you will get on the printed page. This is
accomplished by applying the profile of the specified output device and the monitor
profile to the image file to appropriately limit the gamut and gamma of the displayed
image. (see: Color Management)
A 35mm color transparency.
The process of using the computer monitor to accurately simulate what the image will look
like when printed. Proofing on screen rather than with a hard-copy contract proof.
Soft-proofing is only possible when using accurate color management systems and output
simulation display modes.
A colorspace in which colored pigments are added to white paper. We start with White
(paper) which is the presence of all colors and use Cyan, Magenta, Yellow pigments to
subtract from the image to achieve black. The pigments subtract colors from the white
light reflected off the paper. Yellow ink looks yellow because it absorbs (subtracts)
everything except the yellow from the white light that is illuminating the page leaving on
the reflected yellow light. (See: CMY and CMYK)
Tagged Image File Format is an industry standard raster file format, which consists of the
image and header information.
Tones are changes in apparent brightness of a color. (see: Continuous Tone)
Trapping involves the addition of dots or pixels around the edges of an object so that you
don't get white or colored gaps if the image is printed slightly out of register. This is
necessary where two process colors meet but do not overlap. The trap causes a slight
A standard of communication between scanners, imaging devices, digital cameras and the
computer software. According to some, TWAIN is an acronym that stands for "Toolkit
Without An Interesting Name". According to others, TWAIN is an acronym that stands
for "Translator Without An Interesting Name". According to the TWAIN Working
Group, TWAIN stands for TWAIN since they have never officially expanded its name to a long
This is a process where by the perceived sharpness of an image is enhanced by increasing
the contrast along the edges where different tones meet.
Vector Graphics use mathematical descriptions rather than rows of colored dots (Bit
Mapped). Vector based graphics represent objects as geometric shapes; straight lines,
arcs, etc. They can be scaled and rotated without a loss in quality. Vector graphics are
used for illustrations and typography. Postscript is a vector graphic software language.
Programs like Adobe Illustrator, Aldus Freehand, and CorelDraw are vector programs
An offset press that uses a continuous roll of paper rather than individual sheets
(Sheet-fed). Web Offset is of lower quality then sheet-fed printing but is common where
the press runs involve very large numbers of copies. Because the paper is a continuous
roll and is moving very fast it is more difficult to achieve accurate registration.
The whitepoint of a color display monitor is the color temperature of the monitor. The
color temperature is stated in degrees Kelvin (K) and represents how warm or cool the
white of the monitor is. Uncalibrated monitors generally have a very blue white (often as
high as 9300K) The printing industry uses a standard called D5000 which is 5000K and
closely resembles Daylight.
computer running Windows on an Intel processor chip....your basic PC clone.
"What You See Is What You Get" refers to accurate screen images to print out.
A colorspace used in Photo-CD that is somewhat similar to LAB color in that it uses a
Luminance channel to define the tones and details of the image. YCC also uses two
chrominance channels to define the color of the image.
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