The ABC’s of  Large Format Graphics and Signage   

The world of large format graphics has changed significantly from the days of film negatives and paper enlargements. The originals, the processing methods, and the final output prints have all changed, for the better and with greater choices over the last two decades.

Here is a  brief glossary of  some of the terms you may wish to familiarize yourself with to appreciate the new tools and terms of the industry.

The following is extracted from “Terms of the Trade” in the Buyers Guide, written by the staff of Sign & Digital Graphics magazine.

Acrylic– An extruded or cast rigid plastic characterized by its clarity and ability to accept color.

Additive colors or RGB- An emissive color system using the primary colors, red, green, and blue. Its used in computer monitors, televisions, etc.

Aliasing– Visual stair stepping of of edges that occurs in an image when the resolution is too low for the size of the output.

Aqueous inks– inks that use water as a carrier. Aqueous inks may contain dyes or pigments as colorants.

Aspect Ratio– The height-to-width measurement of an image as displayed on a monitor and ultimately printed. Ratio can change in pixel size, although most computers use a
1:1 ratio.

Attribute– A distinguishing characteristic. The characteristics of color are hue, contrast, and saturation.

Backlit Sign– A sign consisting of a cabinet containing a light source surrounded by one or more translucent faces, illuminated for visibility.

Banner– A sign usually made of fabric, vinyl, or other non-rigid material with no enclosing framework. May be painted, screen printed, digitally printed or decorated with vinyl.

Banner Finishing– Various applications used to complete a banner to include seaming, hemming, pockets, reinforcement, clear tape, hook-and-loop velcro, grommet, etc.

Bevel– A 3D effect that can be applied to text elements, cuts or the edges of dimensional signs.

Bitmap– Refers to images made of rows and columns of monochrome or multi-colored pixels. or dots. for displaying or printing. Bitmap image formats include: AI for Adobe Illustrator Encapsulated Postscript, BMP for Windows Bitmap, EPS for encapsulated postscript, GIF for graphics exchange format, JPEG or JPG for Joint Photographic Experts Group, TIFF for Tagged Image File  Format.

Bleed- the portion of the print that extends beyond the area of the finished print.

Brightness– a measurement of the reflective quality of the medium such as paper or vinyl.

CAD– Computer-aided design. The use of computer programs to design detailed models of tradeshow exhibits, exhibits and displays.

Calendered vinyl– vinyl sheeting squeezed between a series of heated rollers to achieve a small enough thickness for cutting with a knife plotter. Calendered vinyl is generally thicker and less expansive than cast vinyl.

Calibration– the operation of matching color shades and hues between any input and output device.

Cast acrylic– acrylic sheet produced by pouring acrylic resins into a mold and allowing them to cool. Yields best results from laser engraving.

Cast vinyl– a type of vinyl formed from spreading molten plastic mixture onto a carrier sheet in a thin layer, and then baking at high temps to remove solvents and fuse the remaining material into a film. Cast film is usually thinner, more pliable, and more expensive than calendered vinyl.

CMYK– (Cyan, Magenta, Yellow, Black) the four process colors used in most analog and digital printing systems.

CNC– (Computer Numeric Control) communications language used in some robotics and larger machine-controlled cutting devices such as computerized rotors.

Color Curve– Visual control used in photo-illustration and other graphics software to display color measurements and make tonal changes to an image.

Color Gamut– The range and scope of colors that can be reproduced by a specific display or output or display device.

Color Management– refers to the coordination of color with output and display. In output, color management is often handled on a device-by-device basis by imaging production software ( see also RIP).

Color Space– The set or model of how a device organizes color, assigning some formula- such as numeric values- as a way of replicating color. Examples of color spaces are RGB or CMY.

Color Specification– Color values used to numerically  specify a color within a color system, such as the Pantone Matching Color System or PMS system of color spec-ing.

Contour Cut– with vinyl cutters and print-and-cut digital printing devices, the ability to cut around the outline of an image, both on the outer border and along any internal closed loop borders.

Contrast– in graphic design, the use of dissimilar or opposing elements, such as light and dark areas.

Curing– the effect of a chemical change in some inks brought about by the application of heat or ultraviolet light.

Cut Outs– lettering or graphics that are cut from another material. then attached to sign face to provide depth.

Decal– graphics or letters printed on a PSA film, and then cut out.

Delamination– the separation of layers when edges are over-exposed to moisture, temperature extremes, or UV light and result in adhesive failure.

Digital Printer– a printing device that is capable of translating digital data into hardcopy output. Technologies employed in digital printers include inkjet, thermal transfer, electrostatic, and laser photo imaging.

Dmin/Dmax– A measurement of density of a printed image; to be exact, ability of a tone to absorb light. Dmin is the lowest density measure and Dmax is the highest.

Dot Gain– Effect produced when individual sets of dots of color as with inkjet, spread and become larger than their intended size.

DPI– (Dots per Inch) A unit of measure used to describe the resolution capability ofa  given piece of equipment by meanruing the number of individual dots the device can reproduce in a linear inch. The higher the number of dots, the less easy it is to distinguish individual dots, making the image appear sharper.

Drawing Program– An application often called a structured or vector drawing program, used to create and manipulate two-dimensional images and shapes as independent objects as opposed to bitmaped images.

Dress– to prepare and put in a finished condition; such as the edges and corners of a sign.

Dye Sublimation– Imaging process where colorants are vaporized with heat and pressure, and deposited on to a substrate to create an image. Typically the transfer is done to a polyester-based fabric for fabric graphics.  Sublimation inks are mirror printed on a donor material (transfer paper) and then sublimated into the fabric using a heat press.

Dynamic Range– the measurement of contrast from highlight to shadow, and in some cases, the number of shades per primary color. This is one of the best ways to compare true ability of scanner. We use a BetterLight scanning back!

Engraving– a method of marking metal, plastic, or glass in a shallow, negative relief utilizing a bit or a graver. Our engraving is done with a laser.

EPS– (Encapsulated Postscript)- a file type that allows different types of information, such as colors and fill patterns, to be carried between software programs. Files can be bitmapped and vector information.

Extrusion– A Part created by forcing a raw material (usually aluminum framing or  a plastic) through a die to create a specific shape.

File Compression– The process of condensing a file so that it requires less storage space.

Flat- Sometimes refers to rigid substrates which are printed to in UV printing, particularly metals, plastics and wood; an undecorated substrate.

Flatbed Printer– A digital printer designed to accommodate and print directly to various thicknesses of flat materials and rigid substrates.

Foam Board– A type of lightweight, rigid board used for interior signs. Foam boards consist of a foam center sheet laminated on one or both sides by a variety of substrates.

FTP– (File Transfer Protocol)- A standard protocol for transferring data over the internet.To use FTP, FTP software must be set up on both sending and receiving ends of an FTP transmission, and the client must have a username, password, and a valid target address on the server. This is used often for downloading large files and/or for sending to a far off location.

FTP Server– A computer than can receive requests for an FTP link from a client machine or the software on the machine that allows it to do so. This includes FTP server capability. also called an FTP host.

Gamma– Measurement of the degree of contrast between the lightest and the darkest tones of an image. Gamma is also noted as the slope of a curve in measurements of color values, and can be altered for display and output.

Gantry– Bridge on which the spindle assembly of certain computerized routers and engravers travel.The spindle usually travels along the length of the gantry for its X-movement. The gantry can also be mounted on the rails for movement along the Y-axis. This term is also used inkjet printing to describe the bridge on which the scanning print head assemblies is housed on certain flatbed printers.

Gradation– Transition between colors and shades, created by mixing percentages of a dominant and secondary color and then altering them in steps to create the change.

Grommet– A reinforced metal eyelet found in banners used to receive cords and other fasteners.

Header– A separate board above the rest of a sign that gives it a headline or contains a different advertising message for the same product. Most often seen with point-of-purchase advertising.

Heat-Activated Laminates– A type of adhesive used on some film laminates that is not sticky at room temperature but softens when heated, thus activating the adhesive.

Hue- The property of color that indicates the color name, such as purple, blue, or green, that can be specified by particular wavelengths.

Image Processing– Enhancing and manipulating an image, such as by adjusting its size, resolution, or color palette.

Initiation– With UV-curing ink, its the chain reaction of the liquid (monomer0 becoming a solid (polymer) state.

Inkjet Ink– The mixture of colored dyes in a suitable liquid used for digital printing, typically water-based, solvent-based, or uv curable. In our business, we use aqueous based inks with our dye sublimation fabric graphics!

Inkjet Printer– Device that drops liquid ink onto a substrate for printing. A piezo-based inkjet puts ink in a small chamber and then sends a charge to contract piezoelectric crystal lining the chamber and send the ink through the nozzles.

Intensity– The density or opaqueness of a color.

Interpolation– Process of increasing resolution of an image by creating new pixels via an averaging of the size and the colors of surrounding pixels. The result is more dots-per-inch (dpi) in resolution, although some sharpness may be lost.

JPEG/JPG- (Joint Photographic Experts Group) A type of compressed computer file used when sending photographic images through the internet.

Laminate– A process by which different materials are layered and then bonded together using adhesion. The end result may be the creation of a substrate- such as a medium-density overlay (MDO) or the protection of the underlying surface, as when a clear plastic film is laminated to a decorative surface.

Laser– An intense light beam with a very narrow band width, used in engraving and other cutting equipment.

Laser Engraver- Device used a directed,amplified beam of light to cut and mark material.

LED– (Light Emitting Diode) A semiconductor diode the emits light when voltage is applied; a solid state lighting component, used in backlighting for lightboxes.

Light Box- A slim cabinet with internal lighting, used to back light translucent graphic displays.

Magnetic Sheeting– Magnetized strip laminated to a  flexible plastic sheet, usually sold in rolls for magnetic signs.

Negative Space– The area around and within the art and copy, also known as white space.

Nesting– The ability of a RIP program to intelligently arrange multiple print jobs efficiently in order to minimize substrate waste when printing. Also, the efficient placement of images or jobs in order to minimize waste while cutting.

Off-Gassing– A dye-sublimation term referring to the nature of sublimation inks to gradually vaporize and release gases into the atmosphere. This is a harmless product that occurs primarily when the image is placed under stress of heat and/or compression rollers.

Opacity– Measurement of resistance to light passing through a particular substrate.

Optical Resolution– The maximum physical or true resolution of a device without the use of software.

Out-of-Home Advertising (OOH)- The placement of advertising with strategic business or retail settings, often outdoors.

Overlap– Amount of material in a panel that duplicates the previous panel, allowing for proper alignment when assembling and installing; resulting in a bleed.

Overprint White- Printing application in which white ink is used as a background for reverse-printed transparent stocks, such as backlit images. White in this application is somewhat translucent. You can see this in day/night prints used with UV flatbed printing.

Panel- In printing, the division of a job based on the production area of a printing device. If a job size exceeds the production area (width on a printer), it can be divided into panels manually or using a RIP software program and then individually printed.

Pantone Matching System (PMS)- A numbering system for identifying 3000+ colors created through combinations of 14 base colors. The Pantone company produces numerous color-matching systems for standard print and computer applications.

Pass– In inkjet printing, this refers to the number of times a print head passes over a substrate depositing ink. The greater the number of passes, the more ink density is achieved.

Pegged Out– Mounting letters so they are separated from the surface on which they’re being attached. These pegged out letters may mounted this way also to keep stains from washing down on the letters or for visual impact, such as dimensionality.

PDF (Portable Document Format)- Electronic format from Adobe Systems, Inc. that allows the packaging of files for distribution across platforms for display and printing as originally designed.

Pixel– With digital production, a part of a picture that can be located and placed as an element along X and Y axes.

Pixelization– Process whereby the number of pixels are simply multiplied to increase resolution The result is a higher dpi, but the altering of detail from smooth to square-step lines or jaggies.

Plasma Display Panel– A type of flat screen display that is used for television, computer monitors, and dynamic signage. These are often incorporated into a trade show exhibit.

Plotter– Device that interprets information sent from a computer and moves a tool heat to a series of coordinates based on the devices X and Y axes.

Pole Sign– A free-standing sign, usually double-faced, mounted on a round pole, square tube or other fabricated member without any secondary support.

Polycarbonate– A type of plastic used in sign faces, noted for its heat resistance and impact strength.

Polypropylene– Usually a type of plastic used in banners, noted for its flexibility at low temperatures and its resistance to chemicals. Noted for its recyclability.

PostScript– Graphics language that created vector-based images that, by computer code, allows for proportional scaling. Its what makes most scalable type and artwork possible for most Windows and Macintosh-based graphics software.

PPI (Pixels per Inch)- In digital printing, it describes how many of the pixels in a raster image will occur in one inch. The higher the number of pixels-per-inch, the greater the resolution and the less distinguishable each becomes.

Preflighting– Checking a graphic file for potential problems before sending it for final output, essentially to find out font, color,  and other problems. Usually done with software.

Pressure Sensitive Adhesive (PSA)-  An adhesive that activates it adhesive properties only when pressure is applied to the surfaces. Sometimes used to refer to vinyl with a pressure sensitive backing such as PSA vinyl.

Primary Colors– Color that cannot be created by mixing other colors within the gamut of a given color space, but mix to create all other color combinations within that space. Red, green, and blue (RGB)  are additive primaries of emitted light; while cyan, magenta, and yellow (CMY) are subtractive primaries of reflected light. Black (K) is added to CMY to produce denser, truer black images.

Prime– To coat a substrate prior to the application of paint or adhesive.

Profile– In color management, a date file that describes various characteristics and attributes of a computer monitor, printer ink or media, which when used in combination, yield predictable color results.

PVC (Polyvinyl Chloride) – The most common form of plastic used today. PVC is extruded or cast as sheets.

Que- An electronic holding area, usually in random-access memory (RAM) or on a hard drive, where data waits before being sent to a printer for output. Synonymous with spooler.

RAM (Random Access Memory)- The high speed portion of a computer’s data storage that is held on special chips for use in current applications or procedures. RAM is said to be volatile if the stored information is lost when power is disrupted.

Raster Image– An image created by a collection of pixels arranged in a rectangular way.

Rasterization– The process of translating data into a bitmap pattern for output by a digital printing device.

Readability– The quality of a sign’s overall design that allows the viewer to correctly interpret the information presented on it, and the optimum time and distance in which this can be done. Letter size, style, background contrast, and layout all contribute to a sign’s readability (this is outlined in the rules for ADA, Americans With Disabilities Act).

Reflective– The ability of a surface to return some or all of the wavelengths of light that strike it.

Resampling– Changing the resolution of a bitmapped image file without altering the image’s physical size.

Resize– To change the reproduction size of an image so prints can be made smaller or larger. Significant upsizing can result in jaggies.

Resolution– The degree of crispness/clarity of an image. In digital imaging, resolution is measured by the number of pixels (or dots) of color information per horizontal inch of an image. The higher the number of pixels (measured horizontally and vertically) the more precise the pictured image.

RGB(Red, Green, Blue)- The three primary additive colors used by monitors and scanners for transferring and representing color data. In digital imaging, most input and displays are seen in RGB, while printing output is created using subtractive CMYK colors.

RIP(Raster Image Processor)- Software used to create and place dots (or bitmaps) for printing, and then transferring that information to a printer.

Router– In sign-making, a tool that mills out the surface of metal or wood, usually equipped with various bits and able to move material along the X, Y, and Z axis. In digital signage,a router is a networking device whose software and hardware are usually  tailored to the tasks of routing and forwarding information.

Routing– The elimination of material in a substrate, using a router to remove material.

Sampling– Selection by a computer of the best pieces of information; in scanning, the best bits to interpret the scanned image and present the best possible image for editing and printing.

Saturation– The intensity of a specific hue, based on the color’s purity.

Scanner– Device employing a mechanism such as a CCD array to scan an image, printed text or artwork and converts it to a digital image. We use a BetterLight scanning back.

Server– Computers used for limited tasks. In networks, servers act as a hub for storing programs used by different workstation computers; can also act as the machine solely for RIP purposes in large format color printing.

Solvent Inks– Inks that use solvent as a carrie. Commonly used for printing onto vinyl, and offering good outdoor durability. Printers using solvent-based inks emit VOCs and should be vented.

Sublimation– Process in which an image is printed by turning ink or toner, by heat and pressure, into a gas, which then impregnates itself into a substrate such as fabric.

Subtractive Colors– The color system used in printing in which Cyan, Magenta, and Yellow are sued to create all other colors in color printing.When CMY are combined at 100% on a white surface, black is produced. Most printing systems use black (K) pigment also rather than always combining CMY.

Substrate– The material out of which a sign face is made.Wood, metal sheeting, paper, and acrylic are all sign substrates. In inkjet printing or UV direct, a rigid sheet or board is used.

Thumbnail– In digital imaging, a very small version of a larger file used for quick visual identification.

Tolerance- The amount of acceptable difference between a known standard and a measured sample.

Tone– The effect on a color brought about by blending it with another color.

Transfer Paper– A special paper used for the transferring of color images to substrates by using a heat press or similar device.

Typeface– The design of a given set of letters, numbers, and symbols, without reference to size or width.

UV (Ultraviolet) Light- Part of the spectrum from 185 to 450 nanometers. It has both a negative and positive influence on the sign and graphics industry. It is used for curing UV curable inks on a UV flatbed printer. It also causes pigment failure in dyes and inks
on photos and vinyls, especially reds.

Vacuum Table– Used for hold substrated secure to a table, such as on UV flatbed printers or routing/engraving tables. Suction is provided by a vacuum pump.

Value– When dealing with color, value is the measurement of brightness, with zero percent representing black.

Vector– in cut vinyl sign-making, a line segment between two coordinates, on which a knife or tool can be used for cutting or routing.

Vector Image– A computer drawn image that defines graphic pixels through the use of mathematical descriptions of paths and files.

Vinyl– The most common form of plastic.

Wall Mount- A single-face sign mounted on a wall. Another name for a wall sign.

Wayfinding– A system of signage and graphics this is designed to give direction to a given destination. While the copy and graphics on a building’s signs are important to the process, wayfinding also depends on the information inherent in a building’s design.

YCC– Color space developed by Eastman Kodak that defines colors by luminance (Y) and two levels of chrominance (C and C).(Luminance refers to the lightness and brightness of an image. Chrominance refers to the property of a color that describes its saturation, intensity, and colorfulness, used in differentiating two colors of equal brightness and hue.)

Zip File- A file that has been reduced in size by using file compression, using zip software.