G

Galley Proof
Proof of type from any Source, whether metal type or photo type. Also called checker and slip proof.

Gang
(1) To halftone or separate more than one image in only one exposure.
(2) To reproduce two or more different printed products simultaneously on one sheet of paper during one press run. Also called combination run.

Gate Fold
A sheet that folds where both sides fold toward the gutter in overlapping layers.

Gathered
Signatures assembled next to each other in the proper sequence for binding, as compared to nested. Also called stacked.

Ghost Halftone
Normal halftone whose density has been reduced to produce a very faint image.

Ghosting
(1) Phenomenon of a faint image appearing on a printed sheet where it was not intended to appear. Chemical ghosting refers to the transfer of the faint image from the front of one sheet to the back of another sheet. Mechanical ghosting refers to the faint image appearing as a repeat of an image on the same side of the sheet.
(2) Phenomenon of printed image appearing too light because of ink starvation.

Gilding
Mostly in the book arena, gold leafing the edges of a book.

Gloss
Consider the light reflecting on various objects in the printing industry (e.g., paper, ink, laminates, UV coating, varnish).

Gloss Ink
Ink used and printed on coated stock (mostly litho and letterpress) such as the ink will dry without penetration.

Grade
General term used to distinguish between or among printing papers, but whose specific meaning depends on context. Grade can refer to the category, class, rating, finish or brand of paper.

Graduated Screen Tint
Screen tint that changes densities gradually and smoothly, not in distinct steps. Also called degrade, gradient, ramped screen and vignette.

Grain Direction
Predominant direction in which fibers in paper become aligned during manufacturing. Also called machine direction.

Grain Long Paper
Paper whose fibers run parallel to the long dimension of the sheet. Also called long grain paper and narrow web paper.

Grain Short Paper
Paper whose fibers run parallel to the short dimension of the sheet. Also called short grain paper and wide web paper.

Grammage
Basis weight of paper in grams per square meter (gsm).

Graphic Arts
The crafts, industries and professions related to designing and printing on paper and other substrates.

Graphic Arts Film
Film whose emulsion yields high contrast images suitable for reproduction by a printing press, as compared to continuous-tone film. Also called litho film and repro film.

Graphic Design
Arrangement of type and visual elements along with specifications for paper, ink colours and printing processes that, when combined, convey a visual message.

Graphics
Visual elements that supplement type to make printed messages more clear or interesting.

Gravure
Method of printing using metal cylinders etched with millions of tiny wells that hold ink.

Gray Balance
Printed cyan, magenta and yellow halftone dots that accurately, reproduce a neutral gray image.
Gray Component Replacement Technique of replacing gray tones in the yellow, cyan and magenta films, made while colour separating, with black ink. Abbreviated GCR. Also called achromatic colour removal.

Gray Levels
Number of distinct gray tones that can be reproduced by a computer.

Gray Scale
Strip of gray values ranging from white to black. Used by process camera and scanner operators to calibrate exposure times for film and plates. Also called step wedge.

Grind Edge
Alternate term for binding edge when referring to perfect bound products.

Grindoff
Approximately 1/8 inch (3 mm) along the spine that is ground off gathered signatures before perfect binding.

Gripper Edge
Edge of a sheet held by grippers on a sheetfed press, thus going first through the press. Also called feeding edge and leading edge.

Groundwood Paper
Newsprint and other inexpensive paper made from pulp created when wood chips are ground mechanically rather than refined chemically.

GSM
The unit of measurement for paper weight (grams per square meter).

Gutter
In the book arena, the inside margins toward the back or the binding edges.