Pancyprian Graphic Arts flashcards

34 cards. Read the term and the definition here. The deck at the top of this page is optional.

Gestalt law of proximity

Elements placed close together are perceived as a group. In layout it explains why tight spacing links a caption to its image and wide spacing separates unrelated blocks.

Complementary colour scheme

Two hues opposite each other on the colour wheel, such as red and green. They produce maximum contrast and vibration, so they are used sparingly for emphasis rather than for large body areas.

Aspect ratio 1:√2

The proportion of the ISO A-series, where each size is half the previous one and the ratio stays constant. It lets a design scale between A4 and A3 without cropping or distortion.

x-height

The height of lowercase letters such as o and x, measured from baseline to the top of the letter. A large x-height makes a typeface look bigger and often more legible at small sizes.

Tracking versus kerning

Tracking changes the spacing uniformly across a range of characters, while kerning adjusts the space between one specific pair. Tracking fixes overall density; kerning fixes individual awkward pairs.

Measure (line length)

The number of characters in a line of text, ideally 45 to 75. Lines that are too long make the eye lose its place; lines that are too short break rhythm and reading flow.

Widow and orphan

A widow is a single line of a paragraph at the top of a page; an orphan is a single line at the bottom. Both are removed by rebreaking text, not by inserting blank lines.

En dash and em dash

An en dash is half an em and marks ranges such as 10–20; an em dash is a full em and marks a parenthetical break. Using hyphens for either is a common typesetting error.

PDF/X-4

A print-ready PDF standard based on PDF 1.6 that allows live transparency and layers, with output intent and only CMYK, spot or DeviceN colour. It avoids flattening artefacts.

Trapping: spread and choke

Trapping compensates for registration error. A spread grows a light object into a darker neighbour; a choke shrinks a dark object so the lighter background closes in around it.

Total area coverage (TAC)

The sum of CMYK ink percentages at a given point. Coated sheetfed work commonly caps at 300–330%; exceeding the limit causes set-off, slow drying and poor reproduction in shadows.

Rich black

A black built from several inks, often around 60C 40M 40Y 100K, used for large solid areas. Small text stays 100K alone to avoid registration fringing on press.

Rendering intent

A rule for mapping colours between gamuts. Perceptual compresses all colours, relative colorimetric preserves in-gamut colours, absolute colorimetric simulates the target, saturation favours vivid graphics.

ICC profile

A file describing how a device reproduces colour, used to convert between device values and a neutral profile connection space. Profiles are needed for camera, monitor, scanner and printer.

Grey card white balance

A neutral grey reference photographed under the actual light source, used to set white balance and correct colour casts. It makes batch correction of a whole shoot possible.

Anilox roller

A metering roller in flexography engraved with cells that carry a precise ink volume to the plate. Cell count and depth control ink film thickness and therefore colour density.

Dot gain

The increase in printed dot area compared with the requested value, caused by ink spread and absorption. It is larger on uncoated stock and in midtones, and is corrected in the plate curve.

FM versus AM screening

AM screening uses a fixed screen frequency and angle with variable dot size; FM (stochastic) uses randomly placed dots of fixed small size. FM avoids moiré and can hold finer detail.

Spot UV varnish

A UV-cured varnish applied only to selected areas defined by a separate mask layer. It creates a raised gloss contrast against a matt laminate and needs registration tolerance in artwork.

Die cutting and creasing

A steel-rule die cuts the outline while creasing rules press a fold line against a matrix. Creasing prevents board cracking along folds, especially on coated or laminated stock.

Kiss cutting

A die cut that penetrates the face material but leaves the backing liner intact, used for labels and stickers on a roll. It differs from full die cutting, which cuts through everything.

Saddle stitching

Binding by wire staples driven through the fold of gathered sections. Page count must be a multiple of four, and creep must be allowed for on thicker books.

Perfect binding

A binding method where the trimmed text block is glued into a cover, forming a flat spine. Spine width equals half the page count multiplied by paper thickness, plus cover allowance.

PUR adhesive

A polyurethane reactive glue used in perfect binding. It bonds strongly to coated stock, gives better lay-flat than EVA hot melt, and needs a curing period before trimming and packing.

Paper grain direction

The alignment of paper fibres from the paper machine. Grain should run parallel to the spine in books and parallel to the fold in cartons to avoid cracking and poor folding.

Coated versus uncoated

Coated stock has a clay or polymer surface that holds ink on top, giving sharp dots and low dot gain. Uncoated stock absorbs ink, giving higher dot gain and a softer, duller result.

gsm

Grams per square metre, the metric paper weight. It is independent of sheet size, so it is the reliable figure for comparing substrates across suppliers and countries.

WCAG contrast ratio

A measure of luminance difference between text and background. WCAG AA requires at least 4.5:1 for normal text and 3:1 for large text to keep content readable.

SVG

Scalable Vector Graphics, an XML-based vector format for the web. It stays sharp at any size, can be styled with CSS, and is ideal for icons, logos and simple illustrations.

Local exhaust ventilation

An extraction system that captures solvent vapour or dust at its source before it reaches the breathing zone. It is an engineering control and takes priority over respiratory protective equipment.

Waste segregation

Separating waste ink, solvent-contaminated rags, empty containers and paper at the point of production so each stream goes to a licensed carrier. Mixing streams makes the whole batch hazardous waste.

Make-ready waste

Sheets consumed while setting register, colour and ink density before the first saleable sheet. It is a fixed cost per job and dominates paper waste on short runs.

Crossover point

The run length at which the total cost of two processes is equal. Below it the process with lower fixed cost wins; above it the process with lower unit variable cost wins.

OEE

Overall Equipment Effectiveness, calculated as availability multiplied by performance multiplied by quality. It shows how much of a press's scheduled time produces good, saleable output.