gang printing – Grouping related jobs using same paper and inks. Grouping more than one job on a single plate.
gatefold – A four-page insert, having foldouts on either side of the center spread.
GATF – Graphic Arts Technical Foundation
gathering – Collating folded signatures in consecutive order.
GCR – Gray Component Replacement
gear streaks – In printing, parallel streaks appearing across the printed sheet at same interval as gear teeth on the cylinder.
generation – Each succeeding stage in reproduction from original copy.
genuine watermark – Watermark made with a dandy roll.
ghost halftone – A light halftone that may be overprinted with solid copy.
ghosting – Ghost images are unwanted images that reduce print value. Mechanical ghosting develops during the delivery of the printed sheet and is traceable to on-press conditions, ink starvation, form layout, and even to the blanket itself. Chemical ghosting, which occurs during the drying process of ink on paper, is especially bothersome because the condition cannot be detected until the job has been completed.
gild – To cover the trimmed edges of a book with gold or other metallic leaf.
glass – Brief or magnifying glass.
gloss ink – An ink containing an extra quantity of varnish, which gives a glossy appearance when dry.
glued-on cover – A cover fastened to the text with glue.
gluing off – The process of applying glue to the spine of a book to be casebound, after sewing and smashing, and before trimming.
grade – The classification given to paper due to its unique characteristics, which includes brightness, opacity, cotton content, etc.
grain direction – The direction of the fibers in paper.
grain long – Term used to designate that the grain of the paper is parallel to the longest measurement of a sheet of paper. The fibers are aligned parallel to the length of the sheet.
grain short – Opposite of grain long. Grain of the paper runs at the right angles to the longest dimension of the sheet. Fiber alignment in grain short paper parallels the sheet’s shortest dimension.
grainy printing – Printing characterized by unevenness, particularly of halftones.
grammage – The basis weight of paper stated in metric terms of grams per square meter and expressed as g/m2. Thus a sheet of paper 17 x 22″ with a basis weight of 20 lbs. For 500 sheets would be expressed metrically as 75 g/m2. To convert from basis weight to grams per square meter (g/m2), multiply basis weight by 1406.5 (a constant factor) and divide by the number of square inches in base sheet.
graphic designer – A person in the graphic arts who puts together art, text, and other visuals to produce professional printed results.
gravure – An intaglio printing process in which the image area is etched below the surface of the printing plate and is transferred directly to the paper by means of pressure.
gray balance – The dot values or densities of cyan, magenta, and yellow that produce a neutral gray.
gray level – The number of gray values that can be distinguished by a color separation filter — usually 28 or 256.
gray scale – A strip of standard gray tones, ranging from white to black, placed at the side of original copy during photography to measure tonal range and contrast (gamma) obtained.
gripper – A row of clips that holds a sheet of paper as it speeds through the press.
gripper edge – Leading edge of a sheet of paper as it passes through the printing press.
gripper margin – Unprintable back edge of a sheet of paper on which grippers bear, usually 1/2 inch or less.
grippers – In sheetfed printing presses, metal fingers that clamp on paper and control its flow as it passes through.
gross weight – The total weight of merchandise and shipping container.
guide edge – The edge of a printed sheet at right angles to the gripper edge, which travels along a guide on the press or folder. This edge, like the gripper edge, should never be altered or mutilated between the printing and folding operations. It is the shorter edge of the sheet.
guide marks – A method of using crossline marks on the offset press plate to indicate trim, centering of the sheet, centering of the plate, etc.; these are sometimes called register marks.
guide roller – Sometimes called a cocking roller. Located on the roll stand between the roll of paper and the dancer roll. Can be cocked to compensate for certain paper roll conditions.
guide side – The side the press uses to guide the sheet to the exact side toward the operator. Also known as operator or control Side.
guillotine – Device that is used to cut or trim stacks of paper to the desired size, similar to the
gum streaks – Streaks, particularly in halftones, produced by uneven gumming of plates which partially desensitizes the image.
gumming – In platemaking, the process of applying a thin coating of gum to the non-printing areas of a lithographic plate.
gutter – The blank space or inner margin on a press sheet from printing area to binding.
