Object Oriented Art
A form of electronic imagery created by a collection of mathematically defined lines and/or curves.
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Oblique
A slanted font of the Roman interation of the font
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Oblong
In binding, a book bound on the shorter dimension.
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OCR (Optical Character Recognition)
The analysis of scanned data to recognize characters so that these can be converted into editable text.
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Octothorp
# better known as the number sign; it means eight fields
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Odd Sizes
Any nonstandard paper or book size.
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Off Color
Paper or ink which does not match the sample.
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Offprints
Additional sheets printed with the initial order, which are cut into single pages and assembled as separate articles, bound by stapling once in the upper left corner.
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Offset
(1) Wet ink transferred from one sheet to another in a load of printed sheets; also called Set Off.
(2) Short for Offset Lithography.
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Offset Lithography
The most common form of lithographic printing, in which the image area and nonimage area exist on the same plate, separated by chemical repulsion. To print, ink is offset (transferred) from the plate to a rubber blanket and then to the paper.
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Offset Paper
Paper which is strong enough to resist the tacky inks and considerable moisture encountered in offset printing.
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Old Style
Nnumbers designed to match lower case in size and color 123456789
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Opacity
The property of paper which minimizes show through of the printed image from the opposite side of the sheet, or the sheet under it.
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Opaque
(1) An area or material which completely blocks out unwanted light; a filter may be opaque to only certain colors.
(2) A red or black liquid used to block out or cover unwanted clear or grey areas on a negative.
(3) White opaque used to cover unwanted black images in an original copy (on white paper).
(4) To paint out areas on a negative which are not to print. See also: Blocking Out.
(5) The property of paper that makes it less transparent.
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Opaque Ink
An ink that conceals all color beneath it.
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Opaquing
Removing pinholes or other small transparent defects in a negative; also called Spotting Out or Blocking Out.
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Open End Envelope
An envelope which opens on a short dimension.
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Open Negative
A negative slightly underexposed and/or underdeveloped, so the image formed will be slightly larger than normally obtained. An open negative will result in fuller or darker printed matter.
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Open Side Envelope
An envelope which opens on the long dimension.
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OPF (One-Piece Folder)
A one-piece mailing carton, tailor-made to fit a specific book or set of books.
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OPI
An acronym that stands for Open Prepress Interface. An OPI based workflow allows for individual documents to contain low resolution placement images with reference calls to the high resolution images when output to high resolution devices. The result is less transported data.
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Optical Center
The center of a rectangle as it appears to the eye; usually a point slightly above geometric center; about 2/5 from the top of the rectangle.
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Optical Disk
A type of recently developed high capacity computer storage disk which stores information in a mode similar to a CD-ROM but is erasable and reusable.
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Optimized
A process that is performed on a PDF file that orders the file data and removes redundant information. This process will decrease the size of PDF files.
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Original
The artwork, mechanical or other material furnished for printing reproduction; usually refers to photographs or drawings for halftone reproduction. More commonly called Photocopy or Camera-ready Copy.
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Orphan
the first line of a paragraph that is at the last line of a page
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Out of Register
(1) Descriptive of pages on both sides of the sheet which do not back up accurately.
(2) Two or more colors not exactly aligned when printed.
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Outline Font
A font type that uses curves and lines to describe the font. Since these fonts are described mathematically using curves and vectors
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Outline Halftone
A halftone image which is outlined by removing the dots that surround it; also called Silhouette Halftone.
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Outline Letter
A letter form drawn in outline only; there are no solid parts.
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Outlined Image
Letter forms that are defined by an outline and are hollow on the inside.
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Outside Margin
See: Trim Margin.
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Over Pressure
Too much pressure, causing ink to tend to plug letters and especially halftone dots.
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Overhang Cover
A cover larger in size than the pages it encloses.
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Overlay
In artwork, a clear acetate sheet or tissue with color separated as it is to be photographed; sometimes confused with Tissue Overlay.
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Overlays
Color screens that are layered to produce other colors.
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Overprint
The top most layer of a document that leaves any subsequent layers alone and prints on top of them. <>
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Overprinting
Double printing; printing on an area that already has been printed; usually refers to printing black type over a halftone or colored background. See: Surprint.
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Overrun
Copies printed in excess of the specified quantity.
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Overset
In composition, type set in excess of the space allowed; where the type in a line exceeds the stated measure.
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Oversewing
A method of machine sewing, often used in Library Binding, in which stitches are made through the section, forming a lock stitch with each separate section, and independent lock stitches along the back. An oversewn book does not lie open flat.
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Oxidation
A chemical reaction which hardens the ink vehicle and makes the film of ink reasonably rub-proof.
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