O

object-oriented graphic:
a graphic created with geometric elements that are saved in a draw-type or EPS file format.
off-line:
something not presently active or available for access in a system.
offset printing:
term commonly used to refer to offset lithography. The printing process where ink is transferred from the plate to the rubber blanket, then to the paper.
offset paper:
generally refers to paper that is manufactured specifically for use on offset presses. It is characterized by good internal bonding, high surface strength, freedom from fuzz, pick-resistance and freedom from curl. This paper must be relatively impervious to water.
oil mounting:
in scanning, it is possible as well as necessary sometimes to mount originals (usually 35mm) in oil. In cases where the original has been mishandled, has surface abrasion (on the base) or when exceptionally large reproductions are necessary (over 1000%) the original is mounted in an optical oil on the small scanning drum.
on-line:
something active or available for access in a system.
onion skin:
a specific lightweight type (kind) of paper usually used in the past for air mail. Seldom used today (in the typewriter era).
one-side coated printing paper:
paper coated on one side only.
OPI:
open prepress interface. A descriptive language developed by Aldus and prepress vendors to provide a standardized link between desktop publishing and prepress systems. An OPI file is actually a viewing file which provides a link between the image placed in a page layout and the high resolution separation. It is automatically swapped out when the file is prepped for output.
opacity:
the property of a sheet which prevents print areas from showing through the paper to the other side.
opaque:
that property of paper which prevents “show-through” of printing, or other marks; on or in contact with the backside. In photoengraving, to paint-out areas on the negative that must not appear on the plate.
opaque ink:
an ink that conceals all color beneath it.
open face window:
a window opening with no cover.
open prepress:
interface Hardwareand software that link desktop publishing systems with color electronic prepress systems.
optical brightness:
optical brighteners or fluorescent dyes are extensively used to make high, bright blue-white papers. They absorb invisisble ultraviolet light and convert it to visible light falling into the blue to violet portion of the spectrum, which is then reflected back to our eyes
optical character recognition (OCR):
the ability of a scanner with the proper software to capture, recognize and translate printed alphanumeric characters into machine readable text.
optical scanner:
input device that translates human-readable or micro-form images to bit-mapped or rastered machine-readable data.
optical storage:
the means of storing or archiving data on optical discs such as CDs or laser discs.
orientation:
the relative direction of a display or printed page, either horizontal (called “landscape” orientation) or vertical (called “portrait” orientation).
orphan:
one or more ending lines of a paragraph at the beginning of a page or column and separated from the rest of the paragraph at the end of the previous page or column.
orthochromatic:
photographic and lithographic films which are insensitive to red but sensitive to ultraviolet, blue, green and yellow areas of the spectrum.
Outline Mask:
An electronic filtering function that can trace an area or object in an image and extract it. A silhouetting function used in page makeup is also referred to as an outline mask.
outlook envelope: window envelope.
outer form:
form (side of a press sheet) containing images for the first and last pages of the folded signature (its outside pages) as compared to inner form.
outline halftone:
halftone in which background has been removed or replaced to isolate or silhouette the main image. Also known as halftone and silhouette halftone.
output:
information that has been manipulated by the central processing unit (CPU) of the computer, and displayed either on the video monitor or rendered on paper or film as hard copy, or saved on disk in a digital format.
output device:
any device by which a computer transforms its information to the “outside world.” In general, you can think of an output device as a machine that translates machine-readable data into human-readable information. Examples: printers, micro-form devices, video screens.
output resolution:
stated in lines per inch or lines per millimeter, output resolution reflects the number of pixels per unit size the plotter can put onto the film.
Overlay:
Layer of material taped to a mechanical, photo or proof. Acetate overlays are used to separate colors by having some type or art on them instead of on the mounting board. Tissue overlays are used to carry instructions about the underlying copy and to protect the base art.
overlay proof:
color proof consisting of polyester sheets laid on top of each other with their image in register, as compared to integral proof. Each sheet represents the image to be printed in one color. Also called celluloid proof and layered proof.
overprinting (double printing):
printing over an area that has already been printed. Often used in color printing in order to enhance a particular color, or contrast and distinguish a particular color from other similar colors. It is used when the normal process color system is unable to discern close color differences, but are required by the customer.
overrun:
due to machine speeds and/or set-up losses, overruns and under runs are unavoidable on making orders. Percent over or under varies with size of order. The percentage is lower on high runs.