H

hairline register - Register within ± 1/2 row of dots.

halation - In photography, a blurred effect, resembling a halo, usually occurring in the highlight areas or around bright objects.

half binding - A style of binding wherein the shelf-back and the corners are bound in a different material from that used on the sides.

halftone negative artwork (screened negative) - The negative film produced when continuous-tone artwork is shot through a halftone screen.

halftone positive artwork (screened positive) - A photographic positive containing a halftone image.

halftone screen - An engraved glass through which continuous tone copy is photographed and reduced to a series of dots for halftone printing.

halftone - Reproduction of continuous tone artwork with the image formed dots of various sizes.

handmade finish - Paper with a rough finish resembling handmade paper.

hard (dot) - a halftone dot characterized by a sharp, clean cut edge.

hardbound - Another term for casebound.

hardcover (casebound, edition binding) - Nonflexible book binding made of thick, glazed board.

hard-sized - Paper that has been treated with a large amount of size to increase its resistance to moisture. Slack-sized is the opposite.

hard-wood - Wood from deciduous trees having short fibers.

head trim - The amount allowed for the top trim.

headband - A small strip of silk or cotton used for decoration at the top of a book between the sheets and the cover. In hand binding, a real tape to which the signatures are sewn.

headbox - On a paper machine, the box that dispenses the appropriate amount of furnish (pulp) into the papermaking process.

head - The top of a page of text which can be a chapter heading, title line, etc.

head-to-head imposition - An imposition which requires that pages be laid out with the top of a page (head) positioned across the top of the page (head) opposite it on the form.

head-to-tail imposition - An imposition which requires that pages be laid out with the top of a page (head) positioned across the from the bottom (tail) of the page opposite on the form.

heat-set inks - Inks used in high-speed web offset. They set rapidly under heat and are quickly chilled.

hickeys - In offset, spots or imperfections in the printed image traceable to such things as dirt on the press, dried ink skin, paper particles, dust, etc.

high bulk - A paper (normally book paper) specifically manufactured to retain a thickness not found in papers of the same basis weight. Frequently used to give thickness to a book with minimal amount of pages.

high contrast - In photography, describes a reproduction in which the difference in darkness between neighboring areas is greater than in the original.

high finish - A term referring to a paper that has a smooth, hard finish applied through calendering or other processes.

high key picture - A continuous tone photo made up of predominantly highlight (white) areas.

highlight halftone - The lightest or whitest parts in a photograph represented in a halftone reproduction by the smallest dots or the absence of all dots.

high-speed printer - Computer which prints in excess of 300 lines per minute.

hinges - The flexible joint where the covers of a hardbound book meet the spine, permitting the covers to open without breaking the spine of the book or breaking the signatures apart.

hit - An impression from a stamping die.

holdout - A term referring to papers that retain much of the resinous ink components on the surface of the sheet rather than absorbing them into a fiber network. Papers with too much holdout cause problems with setoff.

hue - In color, the main attribute of a color which distinguishes it from other colors. See Chroma.

humidity - Moisture condition of the air. Relative humidity is the percent of moisture relative to the actual amount which air at any given temperature can retain without precipitation.

hydra pulper - Vat with a special type of agitator used to hydrate and prepare pulp for papermaking.

hydration - A papermaking process that involves beating the pulp so as to increase its ability to hold water and produce a paper with the proper moisture content.

hydrophilic - Describes paper with an affinity for water.

hydrophobic - Describes paper that tends to be water repellent.

hygroscopic - Describes paper that readily absorbs moisture.