Knowledge
Large Format Printing Terms
Raster Images
Raster images are made up of pixels, dots of color that work together to form the image. Photographs are always raster files, as well as most images you see online. Raster images will gradually lose quality as you scale them up, creating a rough, pixelated appearance.
Vector Images
Vector images are not comprised of pixels. Instead, they use math equations to determine the appearance of the image. Because of this, vector images can be scaled up or down to any size and they will never decrease in image quality, which makes them ideal files to send to be printed in large formats.
Pixel
Every raster image is made up of pixels; single dots of color that, together, form the image. As an example, a 2-megapixel image has 1,920,000 pixels (1200×1600).
.jpg/.jpeg
A JPEG (saved with the extension .jpg) is the most common file type for an image. Most digital cameras take a .jpg image by default. This is a raster file format that uses color compression to reduce the size of the image file. The compression amount can be adjusted, but .jpg files typically achieve a 10:1 reduction in file size with very little noticeable loss in image quality.
.tif/.tiff
A TIFF file (saved with the extension .tif) stands for Tagged Image File Format standard. This is a raster file that can be saved uncompressed without any degradation of the image.
.eps
An EPS file retains the information of a vector file. This means that .eps images can be scaled to any size without loss of image quality. This is a great file type to send to be printed, especially for large format prints.
Color Profile
Color profiles are generated for printer and paper combinations so that accurate reproduction of colors is possible. They are also very useful in obtaining color matches between monitors and printers to ensure that what is seen on the screen is an accurate representation of the final printed image.
RGB
RGB stands for the Red-Green-Blue color profile. This is typically used in monitors and digital cameras. Colors are defined by the levels of red, green, and blue measured on a scale from 0-256: therefore, pure black is 0-0-0 and pure white is 256-256-256.
CMYK
CMYK refers to the Cyan-Magenta-Yellow-Black color profile, usually associated with four-color printing. Each color is measured on a scale from 0-100. CMYK is a subtractive color scale, so pure black is 0-0-0-100 and pure white 0-0-0-0.
DPI
DPI stands for dots per inch, and refers to the number of pixels within one square inch of an image. A higher dpi results in a higher quality image. The dpi that an image needs to be depends on the size of the print and the distance it will be viewed from. In offset printing, such as magazines or newspapers, 300 dpi is the standard. In large format printing, the dpi can be much lower.
Image Resolution
Resolution expresses the image quality, and is defined by pixel density (dots per inch) or image size (pixels tall x pixels wide).
Resampling
Raster images are often resampled when being enlarged in order to lessen the noticeability of pixelation. Resampling can “soften” images, particularly at sharp borders between colors, but when done by a knowledgeable professional it can enlarge an image with very little loss of image quality.
Banner Seaming Info
When ordering a banner, you don’t want your finishing to have a shorter life than needed for the job. To make sure this doesn’t happen, we have brought together some information to help you decide on proper seaming for your vinyl banner. The most common and popular finishing options are seaming tape, glues, stitching, chemical weld, RF weld, hot air weld and hot edge weld. We break down the pros and cons to each in this article.
Seaming Tape
Seaming tape (or banner tape) is ideal for small banners and projects that need a fast turn around time. It does not last very long and isn’t suited for outdoor environments. It isn’t meant to be used on large or heavier banners. But, it is a perfect solution for a short term or one time use event.
Banner / Seaming tape is double-sided industrial tape and it’s applied to the banner to create a hem or it can be stuck to the backside of the material with the release liner unpeeled so the installer can peel the liner backing. Seaming tape requires no special equipment for installing and it applies just like double sided tape.
Glue
Glue places a layer between two pieces of banner. Epoxy and acrylic (found in the glue), are made to work for vinyl. However, the modification shortens the adhesiveness of the glue.
Glue isn’t a good choice for long term banners, but it is a perfect fit for one-time events like birthdays, grand openings or other special sales or events.
Velcro
Velcro is a quick and easy way to simply stick a banner to a surface. Male or Hook refers to the rough side of the velcro surface and can be sewn on or applied to your banner like tape.
Loop or Female is the smooth style and can be sewn on or applied like tape.
Stitching / Sewing Machines
When seaming tape won’t do the job, a chemical weld won’t quite last long enough and RF welding is not in your budget, stitching and sewing can be the solution to consider for your banner. Although sewing stitches can be more complicated – it’s worth the trouble, especially in windy conditions. It is one of the most durable alternatives to withstand weather conditions. GH uses industrial UV coated thread. Awning Keder bead, pockets, hems and fabric tiling can all be done using thread and a sewing machine. Mostly all fabric banners are finished with the sewing machines. Double-sided street pole banners and pole pockets are created using a sewing machine.
Chemical Weld
Chemical weld is similar to glue but it has a much more permanent seam. There is a chemical process that dissolves together the two parts of the banner. The chemical weld can be applied by brushing, pouring or squirting the chemicals onto the vinyl and press the two pieces together. Application doesn’t require much skill, but there are a few tips and safety precautions that need to be considered.
The industry standard is HH-66 also known as a bodied adhesive or bodied solvent. When it is applied properly, it provides a super strong, waterproof, flexible bond. It is very resistant to temperature and extreme weather conditions. It’s great for patch work and sealing vinyl.
Chemical weld can be dangerous if not handled properly. It contains combustible solvents, so make sure to keep it away from any flames and keep the can securely closed when not in use. If you’re using the chemical weld in an area with minimal ventilation, make sure to have a fan or another device to move the air. You should also wear gloves when using a chemical weld as it can cause irritation if it has contact with the skin.
RF, Hot Air or Hot Wedge Welding
RF Welding fuses materials together by applying radio frequency energy where the materials are joining. It is not heat welding, it’s comparable to your microwave at home. The result is as strong as if the two materials were one. It is more expensive that chemical welding but is much stronger and lasts longer.
Hot air (leister) and hot wedge (miller) welding provide the strongest hold and helps your banner withstand wear, pressure and weather better than tape, stitching or glue. Wedge welding requires 1/2″ of bleed and a 1/2″ of material for finishing. Hot air requires an extra 2″ at the sides of the material for finishing. The materials are actually fused together into one. It is a great solution for banners that need a long life, are used frequently or will be placed outdoors.
Large Format Inks
When printing a wide format job, there are several inks and printing processes that can be used depending on the nature of your project. Your GH Sales Consultant can help you choose the best process for your needs, but here is a quick overview of the different methods, inks, and applications.
Latex Inks
Latex inks are the most eco-friendly option. They are water-based, making them non-toxic and non-flammable. Latex Printers use heat to rapidly cure the ink to the media. The final print will be very durable, resistant to water, heat, and scratches. It’s also flexible, making it perfect for adhesive prints, outdoor signage, or vehicle wraps. Latex printing produces high-quality prints with very vibrant color without the environmental hazards of solvent inks.
Talk to your GH sales consultant to help you determine the correct inks and printing methods for your specific project.
UV Inks
A newer method is UV printing, which uses special ink formulated with chemicals that instantly harden when exposed to ultraviolet light. UV inks are more environmentally friendly; because the ink is immediately dried from the UV lamps, there are virtually no chemicals released into the air and print time is very fast. UV Printing also uses less ink than other methods because there is very little evaporation and less absorption into the stock. Another advantage to UV Printing is that UV inks can print onto almost any substrate that can fit through the printer, and the color is very resistant to fading. UV ink is less conformable to media that stretches such as adhesive vinyl, as the ink will begin to crack if excessively stretched. UV ink is exceptionally tough and durable, and does not need an over-laminate when being used outdoors the way that latex and solvent inks do.
Solvent Inks
Solvent printing was the first method used in Grand Format printing. It has excellent performance and affordability but isn’t very eco-friendly; it requires special ventilation to avoid exposure to hazardous fumes from the toxic solvents. It also requires some time for the ink to dry and fully cure. Solvent inks produce a very durable, scratch-resistant product, perfect for indoors, or outdoor applications like banners or adhesive graphics. At Graphics House, we use Solvent ink for all of our mesh banners.
Glossary
A few of the most commonly used industry terms.
A
Appliqué
A method of flag and banner production in which a fabric is sewn to another base fabric, and the surrounding excess fabric is then cut away, leaving sewn details.
B
Backing
A layer of material added to the back of a single-sided banner in order to give the finished banner greater opacity and/or greater body or thickness.
See Also: “interliner”
Banner
A strip of cloth or vinyl used for advertising a person, idea, organization or business. Banners differ from flags in that they are expected to hang open and be readable with or without the benefit of wind.
See Also: “flag”
Bunting
Strips of fabric, usually colored, that are used to decorate a large area or stage. Bunting is often used at political events and rallies. Bunting can be laid flat, or can be ‘swagged’ around a stage.
C
Cord and Tassel
A gold-toned braided rope with decorative tassels on the end, used to decorate a formal indoor flag setup, or parade flag.
Cotton
A fabric sometimes used as backing for banners.
D
“D”-ring
A metal loop in the shape of the letter “D” used to finish the corners large flags and banners. Snap hooks attach to “D”-rings.
DPI or ‘dots-per-inch’
DPI is a way of expressing a bitmap or raster image’s resolution. An image that has a higher DPI uses more (and smaller) ‘dots’ (or pixels) to create the image, and so can be enlarged without breaking down. If an image of insufficient DPI is enlarged too far, it may pixelate.
Dye-sublimation
A banner manufacturing method in which special inks are used to put four color process images and photographs directly into the weave of a fabric.
E
Embroidery
Fine needlework that creates shapes and images on fabric using tightly stitched areas thread.
F
Finial
A pole ornament that appears on the end of a flag or banner pole. Finials can take simple shapes like a ball or a spear, but can be specialized for specific flags. The Israeli flag, for example, should be displayed using the ‘Star of David’ finial, and the U.S. flag typically has an eagle-shaped ornament.
Flag
A strip of cloth used for advertising a person, idea, organization or business. Flags differ from banners in that they are expected to catch the wind and are usually single-reversed.
See Also: “single-reverse”
Flame-Retardant
Some fabrics and vinyls are specially treated to resist catching fire, in accordance with fire codes. This can often be an issue in event halls and convention centers. Always check with your convention center to check their flame-retardant policies. Some convention centers will not allow fabric displays to be used unless they meet certain flame-retardant standards.
Fly-End
The trailing edge of a flag, farthest from the flag pole. The fly-end of a flag is the part of the flag that often endures the greatest stress from wind. When a flag whips in the wind the fly-end receives most of the energy. For this reason the fly-end of a flag gets some extra reinforcing.
Formal Flag Setup
Flags meant to be used in either parades, in offices, or on stages. These flags differ from conventional outdoor flags because they are usually fringed and have pole sleeves. A typical formal flag setup includes the fringed flag, decorative cord and tassel, an oak pole, and a gold-toned base so that the entire assembly can stand vertically.
Four Color Process
A way of describing a color gamut through four “CMYK” color values (Cyan Magenta Yellow BlacK). This term is sometimes used to refer to any imaging process used to render a photographic image.
Fringe
A decorative trim that is sometimes put on the edges of flags and banners. Fringe is usually a yellow-gold color, but other colors are available. Fringe is not meant to withstand weather, and should be kept dry.
G
Gamut
Every color combination that is possible to produce with a given set of colorants on a given device or system. When a color is said to be ‘within’ a printing machine’s ‘gamut’, it means that the color can be reproduced by the printer. Colors described as ‘outside the gamut’ cannot be reproduced.
Grommet
A small, metal, reinforced ring placed in the corners and/or edges of banners and flags. A banner or flag can be attached to nearly anything with a grommet. For very large flags or banners that will be subjected to great wind or weather, “D”-rings can be used. Grommets also appear on the cotton headers of outdoor flags.
H
Halyard
The rope used to raise or lower a flag or banner.
Header
A thick strip of cotton or other strong material attached to the end of a flag, to reinforce the edge of the flag. Grommets are placed in the corners of the header, which are used to attach the flag to a halyard.
Hemming
To reinforce the edges of a banner, the material is turned over on itself once or multiple times, and then sewn.
I
Inkjet Printing
A method of large format printing where a ‘print head’ move across a substrate, laying down small dots of ink, which, when viewed together create an image.
Interliner
An additional layer (or layers) of fabric placed between the two sides of a double-sided banner. The interliner is added so that the two sides of the banner will not ‘show through’ when sunlight hits the banner.
L
Lamination
A thin film of protective material usually laid on top of the final image to protect it from ultraviolet radiation, grit and other damaging forces. Signs mounted to foamcore, vehicle graphics and floor graphics usually get some form of lamination.
Temporary or one-time use signs usually don’t require lamination.
Large Format
A term used to refer to any ‘large-sized’ digital printing. It usually refers to inkjet or solvent printing technologies.
M
Mesh
A type of vinyl substrate typically used for very large outdoor wall banners. Printing an onto mesh cuts down on the banner’s weight significantly, making them easier to install. Also, the open weave of the mesh allows wind to pass through the banner more easily.
N
Non-Tangle Rod
A metal rod attached to the bottom edge of a flag, used to help prevent a flag from wrapping around a flagpole and reducing some of their movement due to wind.
Nylon
A synthetic fabric substrate.
O
Outrigger Pole
A way of installing an outdoor banner pole. A single pole is installed onto the face of the building, and the top of the banner is attached to the pole. The bottom end of the banner is allowed hang free.
P
Pantone Colors
A color-matching method invented by Pantone, a company which publishes books with colored tiles. This system allows people to discuss color in a objective way. Also called ‘PMS colors’ (Pantone Matching System).
Parade Banner
A style of banner used in parades.
A parade banner is typically horizontal, with a pole sleeve along the top. A pole is inserted across the top of the banner, and marchers can hold the pole (and the banner) and march comfortably. Parade style banners are usually 30 inches in height, and their width can vary.
Parade Flag
A parade flag is very similar to a formal flag setup, but without the base that allows it to be stood upright. A parade marcher will typically use a belt with a special cup in which the butt of the pole can be rested.
Pennant
A triangular shaped flag.
Pennant String
A string of pennants, attached to line, used as retail decoration.
Pixelation
When a bitmap or raster graphic is enlarged beyond what it’s resolution can handle, the individual ‘dots’ or ‘pixels’ can be seen, making the image unattractive and seem ‘blocky’.
Podium Banner
A type of small banner attached to the front of a podium or lectern, to identify the organization hosting the event, or to indicate who the speaker represents.
Pole Hem / Pole Sleeve
A way of finishing a banner where the edge of the banner it turned over itself in order to create a sleeve through which a pole can pass.
Polyester
A synthetic fabric that can be used to make banners. Polyester fabrics are useful in the dye sublimation process because they are uniform and can be made to simulate the appearance of other fabrics.
R
Raster or Bitmap Graphics
A type of graphic file that stores visual information in the form of pixels, discrete squares of color. Raster images that are intended for reproduction on banners or flags must be of a sufficiently high resolution or pixelation may occur after the graphic is enlarged.
S
Satin
A lustrous, shiny fabric, suitable for making indoor banners.
Shear-Cut
A method of finishing banners where the edges of the banners are cut using a straight edge and a razor-knife.
Silk-Screening
A method of manufacturing banners in which a frame is built. The frame has a mesh stretched across the frame. By blocking out certain areas of the screen and leaving others open, inks can be passed through the mesh screen, forming a pattern on a substrate underneath the frame.
Single-Reverse
Most flags are designed to be single-reverse, which means that the image or message on the flag reads correctly on only one side, and is ‘reversed’ on the other side.
Snap Hook
A spring-loaded metal hook attached to halyards that is used to attach flags and banners.
Solvent Printing
A kind of printing that uses solvent inks. Solvent inks are chemically aggressive, which work their way down into the substrate. Solvent inks can be used to create durable outdoor banners.
Squeegee
A tool used to draw ink across a silk screen.
Step-and-Repeat Banner
Step-and-repeat banners are large banners used as backdrops against which celebrities and event attendees can be photographed. They’re called step-and-repeat banners because a logo or logos are repeated on them, usually staggered. In this way, no matter how people are photographed, the event sponsor’s logo is always present somewhere in the photo.
Street Banners
A type of banner installed on the lamp posts. To see some examples of this kind of banner, please visit our gallery page.
Substrate
Any material that receives an image. Substrates can be soft materials like fabrics and vinyls, or harder surfaces like Sintra, glass, or foamcore. The substrate is whatever ‘receives’ the design or image.
Swallowtail
A specific kind of flag shape in which the fly-end of the flag tapers to two points.
T
Table Banner
Any banner that is meant to cover or adorn a table. Often used at trade shows or other events, a table banner can take on many different forms. Some table banners are attached just to the forward edge of the table surface and hang over the front. Others can drape over the entire top of the table and the front. Others can completely cover a table on all four sides.
Tassel
A bunch of cords gathered at one end. Tassels are used to decorate formal flag setups.
Tie-Back
A way of fastening an outdoor banner back to a building. A tie-back allows a banner to move (as it should, in order to catch the eyes of people passing by) but lessens the chance that it could wrap around its pole.
Top-and-Bottom Poles
Some banners are installed with two poles, one on the top and one on the bottom. These kinds of banners are typically very narrow. This sort of banner installation usually requires that the banners receive wind vents.
V
Vector Graphics
A vector image is one of the two major types of graphic formats (see also: raster or bitmap graphics). Vector graphics create an image by using many individual objects. Each of these objects can be defined by mathematical statements and has individual properties assigned to it such as color, fill, and outline. Vector graphics are resolution independent because they can be output to the highest quality at any scale.
Vexillology
The scholarly study of flags.
Vinyl
A substrate made of extruded plastic material, often used to make outdoor banners.
W
Window Lettering
Pressure-sensitive (adhesive-backed) vinyl material can be machine cut to add window graphics.
Wall Banner
A kind of banner, almost always single-sided, that is attached flat against a wall, or other vertical barrier.
Wind Slits or Wind Vents
Small openings cut into a banner (and rarely, flags) to allow the wind to pass through the banner. A large banner without wind vents is really more of a sail. Without vents to reduce some of the wind force on a banner, the banner could rip.
