Digital Fine Art Glossary

We have produced this glossary to help you better understand some of the terminology used in both traditional and digital print making. Please use our digital fine art enquiries page if you require further information or have any questions about printing your digital artwork.

Adobe RGB (1998)

ICC-based colour management workflows are becoming the standard for ensuring reliable colour reproduction from screen to print. Many professional workflows are built around the Adobe RGB (1998) ICC colour profile.

Artifact

A compression artifact is a noticeable distortion of an image or loss of image quality due to lossy compression techniques. Compression is a way to reduce file size by sacrificing image quality. Compression artifacts occur in image file formats such as JPG. The visible signs of excessive JPG compression are artifacts, which include areas of similar colour that become "blocky" and sharp contrasting edges in the image will have "vague smudges" surrounding the sharp edges.

Original Image	Loss of edge clarity and fuzziness due to heavy JPG compression

Artists Proof

These are the copies of the final proofs that the artist signs as they are getting the colours and tonal values correct before commencing the print run itself. More commonly seen in intaglio and screen processes, as in litho (on a commercial level) they are approved before printing starts. This is enabled more now, as with computer technology, a lot of the proofing will be done on an inkjet printer that emulates the press colours.

Canvas Print

The reproduction of your photographs or paintings which are printed directly onto 100% pure cotton artist canvas.

Certificate of Authenticity

A certificate of authenticity identifies the process, techniques and materials used to create a limited edition print. The certificate can be signed by both the artist and printmaker and contains information on the artist, the title of the work, the media used and the number and date of the limited edition. It is an excellent selling point as it assures the buyer, and any future buyer, that they can verify the authenticity of the giclee print.

Colour Correction

Manipulation of channels, shades, hues, contrast and levels of individual colours before printing to eliminate any colour casts and imbalances from the original or scanned image.

Colour Management

A system of control over the input and output devices on how they interpret the colours they are using. This is often done in an image manipulation software program such as Photoshop before printing, or for production based environments where more accurate and consistent results are required, RIP software will be used that contains colour profiles created to match colours when printing on different types of paper. This process of getting the file to a satisfactory stage is often referred to as proofing. See also: RIP and Workflow.

CMYK

Cyan, Magenta, yellow and Key (Black). Process colours. A colour system used by printers to combine each colour on a different printing plate to make up a full colour image. 4 colour printing. Most giclee printers will send files to an inkjet printer in RGB however, as RGB provides a better (wider) colour gamut.

Deckle Edge

Hand made and mould made paper has a natural deckle which is the result of how the paper is made. When you tear the border edges of a fine art print printed on mould made paper you can achieve that marvellous finish of a feathery or deckled edge.

Digital Camera/ Scanback

A camera that captures information in a digital file, rather than on film. Digital cameras eliminate the film process of reproducing an image therefore allowing for less colour casts etc. The digital data will also archive better. A Scanback is a professional back for large format studio photography. The digital back scans directly onto a computer and many are capable of creating files of 300 – 500MB. This process is still very costly however, and requires a sound photographic knowledge.

Digital Print

A print that is created on an Inkjet printer from a digital file on a computer. See also Giclee.

DPI or PPI

Dots per inch or pixels per inch. The measurement units of the output device quality of print. It refers to the number of dots or pixels a printer can print per inch. I.e.: a print at 600dpi will have 36000 dots on one square inch or the paper (600 x 600). It also refers to the dots or pixels per inch of a scanned image. See also Resolution.

Dynamic Range

The difference between the dmax and the dmin of an image or print. Dmax is the darkest value a printer can produce and dmin is the lightest value a printer can produce.

File Formats

The information of a digital file is stored in various file extensions or formats. The formats are either based in the application program that created the file, .psd is a Photoshop file for example, or a more universal format that is supported by most imaging programs are TIF and JPG. Some compress information in the image more so it creates smaller files. While this is good for storage space and e-mailing, information will be lost in the image when you come to print it. (TIF, JPG, PSD, AI, and EPS.)

FTP - File Transfer Protocol

FTP (File Transfer Protocol) is the simplest and most secure way to exchange files over the Internet. When using our fine art printing service, this is the best way to upload your image files to Redcliffe, particularly when sending large files. You can, of course, attach your image files to an email, but the email protocol breaks data down into small packets and was never intended to send large files.

Fourdrinier

The Hahnemuhle natural papers are produced on fourdrinier paper machines. This is also called machine made paper. A long wire moving continuously over several rollers is applied to the saturated pulp and the paper web forms. The paper is taken off the wire and inserted into the machine via pre-selected natural felt rollers then pressed and dried in several stages.

The weights in the range are from 150-450gsm and are available in many different sizes and surface texture. As with the mould-made papers it can be used with watercolour paints and other wet and dry techniques, and many printing processes. For giclee printing, the machine made papers tend to be slightly more rigid than mould-made papers.

Gallery Wrap

Gallery wrap or image wrap is continuing parts of an image around the sides of the stretcher bars on a stretched canvas print. It is a method of stretching an artist's canvas over a mitred and wedged wooden stretcher frame, so that the canvas wraps around the sides of the stretcher bar and is secured to the back of the wooden frame. The sides of the canvas are painted or printed so that the image wraps around the edge of the stretcher.

Gamut

In colour reproduction the gamut, or colour gamut, is a certain complete subset of colours. The most common usage refers to the subset of colors which can be accurately represented within a given colour space or by a certain output device.

Giclee

Term referring to a digital print from a digitised image outputted from computer to an inkjet printer. It usually should refer to a limited edition, fine art print, onto archival quality coated paper, and printed with pigment inks, which are UV stable.

To qualify for the title of a giclee print that has longevity, a print must meet the Fine Art Trade Guild standards: it must score 6 or greater on the Blue Wool Scale for lightfastness, and be between 7pH - 10pH, on a minimum substrate of 250gsm.

Greyscale

Greyscale images of this sort, also known as black-and-white, are composed exclusively of shades of neutral gray, varying from black at the weakest intensity to white at the strongest.

Hand Embellished

A process of painting onto a giclee edition after it is printed. The artist will usually pick out certain areas to highlight, either to create a texture similar to the original, or to pick out gold and metallic colours that can’t be reproduced.

Hologram System

A system Hahnemuhle has launched to ensure that artists prints can not be copied, and the authenticity can be recognised. It consists of an alphanumeric hologram that goes on the back of a numbered print, and one of the same number on a certificate of authenticity.

Intaglio

Refers to a print process where the image is created by a metal plate being bitten with acid or scratched on the surface of the printing plate. When the plate is inked up, ink will be pushed into the bitten lines or areas and this is what will create the image in reverse directly onto the paper when rolled thorough the press. Processes include etching, engraving, mezzotint, drypoint, aquatint and photo etching.

Interpolate

A digital image can be enlarged in size by adding new pixels to the image, but interpolation increases the image by guessing what pixels are required and uses information from the surrounding pixels to achieve this. Although the overall picture count will rise image quality can actually suffer and definition is often reduced.

Iris Print

A certain type of inkjet printer that was first used for reproducing artwork onto fine art papers.

IT8

is a range of colour targets for colour characterisation of different devices and media such as scanners and printers. Used for making colour profiles to get consistent colours on different papers. This is the industry standard colour reference tool for calibration input and output devices.

JPEG

JPEG or JPG is a commonly used method of lossy compression for digital images. The degree of compression can be adjusted, allowing a selectable tradeoff between storage size and image quality. JPEG typically achieves 10:1 compression with little perceptible loss in image quality.

LAB Colour

LAB colour space is the most complete colour model used conventionally to describe all the colours visible to the human eye. The three parameters in the model represent the luminance of the color (L, the smallest L yields black), its position between red and green (a, the smallest a yields green) and its position between yellow and blue (b, the smallest b yields blue).

Lightfastness

The ability of dyes or pigments to resist changing colour by fading when exposed to light. Often expressed as the rate at which dyes, pigments and paints change colour or get lighter as a result of being exposed to UV or daylight, heat, acids or alkalis. The expected or estimated life of a print can be measure by tests such as the Blue Wool Scale (UK) and the Wilhelm Laboratory reports (USA). However the lightfastness can be affected by the combination of ink and paper used and therefore all the inks may not fade at the same rate.

Light Fastness:

Limited Edition

A limited edition has a closed number of prints in the print run. Once this number of prints has been made, no more copies of the images can be reproduced or sold. (Apart from the artists and printers proof) This can add value to a print. In Lithography 850 is the usual standard number in the print run, at the artist or publisher’s discretion. With Giclee the numbers can be much smaller. The Fine Art Trade Guild conditions state that if it is declared a limited edition print no more tan 1950 copies (including the artists proof) must be produced.

Lithography

High volume, 4-colour separation, process ink based printing process. Commercially, offset lithography and is the quickest and commonest form of photomechanical reproduction. Artwork is scanned then separated in the CMYK colour channels onto 4 printing plates, printed in succession to create a full colour image. Separate colours can be added on further plates to create special effects such as gold ink or a varnished area that can not be made up from CMYK in the standard Pantone range. These are called spot colours.

Artists still use offset and stone lithography to create artwork, but by hand it is a much lengthier process. The basic technique for both methods is that grease repels water and these are the areas that will remain white, the rest of the areas will accept ink and therefore print.

Mould Made Paper

The Hahnemuhle mould made watercolour boards offer excellent colour flow and brightness. This makes them usable not only for watercolour but also gouache, tempers, lavis, and charcoal and pencil drawing. Produced on a cylinder mould-made machine, and then taken off and fed through natural felt rollers. The mould-made papers range from 200-600gsm, and tend to have a softer surface texture.

Offset Printing

Offset printing is a commonly used printing technique where the inked image is transferred (or offset) from a plate to a rubber blanket, then to the printing surface.

Open Edition

Referring usually to offset lithographic prints and the fact that there is no limit to the number of prints produced from this image. An open edition also means it can be produced in various sizes, on cards and clothes etc.

Pigment Ink

Pigment inks are literally pigments of colour ground down very fine and suspended in a liquid to make ink, compared to dye ink, which is a dye suspended in liquid. As with other types of colour, pigment produces a more lightfast material or ink that will take longer to fade. Current pigment based inks on the market can be anywhere up to 100+ years lightfast, but this depends on a number of factors such as ink manufacturer, paper type and storage conditions.

Platemark

The indentation at the edge of a printed image caused by the plate pressing into the paper as it goes through the printing press. These types of marks are created in etching and intaglio print processes where the image is contained on a metal plate.

Printers Proof

Used by printers to verify the colour and quality of an edition of an original print. They are used by the printer or artist to proof the edition and are usually retained by the printer.

Profile

A file that communicates to a device or software application how to properly handle and express colour information. Refers to specific colour settings to be used with different papers and ink sets, to create the correct colour reproduction. It is used to transform from one colour space to another.

Resolution

The higher the resolution of a scanned image the more information is held. The resolution of an image is measured in ‘dpi’ dots per inch. The ‘dots’ refer to the pixels that make up a digital image. So for example a resolution of 150dpi means that in each inch of the image there are 22500 pixels (150 x 150) in every square inch. This is also referred to as ppi, pixels per inch and sometimes just as ‘res’ which is the metric resolution per millimetre (e.g.: res 12 is equivalent to 305 ppi).

RGB

Red, Green and Blue. This colour system cannot be used for planographic printing such as lithography, but is often used in digital printing, the files stay in this format. The actual inks in the printer however are still CMYK, often with the additional colours of light cyan, light magenta, an extra black and sometimes orange and green (called hexichrome) to give wider colour gamut and better tonal graduation. RGB are the primary colours of light, which are different to the primary colours of pigments in paints and inks.

RIP

Raster Image Processor. Raster images are made from bitmap rather than vector grids. Rasterisation is the process of converting mathematical and digital data into dots by an output device. Therefore, the job of a RIP is not only to do this job but it also helps to increase images to large sizes without as much loss of information or pixelation as doing the same process in PhotoShop. ICC profiles can also be attached to the RIP software for colour management purposes.

Scanner

An input device in which to capture a piece of artwork onto a computer as a digital file. A scanner uses light sensitivity to translate the picture into a pattern of dots. Types of scanner: Flatbed scanner, drum scanner, transparency scanner, scanback and digital camera.

Serigraph

A term used to describe silk screen prints, or prints where flat colour is built up in layers to create an image. Each colour requires a separate screen, and therefore makes it a costly process for doing limited edition print runs.

Silk Screen

Silk screen printing is a stencil method of print making in which a design is imposed on a screen of silk or other fine mesh, with blank areas coated with an impermeable substance, and ink is forced through the mesh onto the printing surface. It is also known as silkscreen, seriography, and serigraph.

Substrate

Substrate is a term used in printing, mainly industrial printing, to describe the base material that images will be printed onto.

Tiff

Tagged Image File Format (abbreviated TIFF) is a file format for storing images in a lossless format, popular among illustrators, graphic artists, the publishing industry, and both amateur and professional photographers in general.

Workflow (closed loop system)

This refers to having a complete system of scanner, monitor, software, printer and paper which are all calibrated up to each other. This makes colour management easier, quicker and more accurate.