Glossary of terms

Bronzing

This is a rare effect where the colour of an ink on paper changes it's appearance when viewed at different angles, often taking a metallic hue.
This effect is often confused with gloss differential (see below)  

CIS

Continuous Ink system. An adaptation made to a desktop printer allowing a continuous feed of ink to be supplied to the print heads without using disposable ink cartridges. Despite high initial costs, this can deliver significant cost savings for heavy users of desktop inkjet printers.  

CMS

Colour Management System  

Colourspace

This is the definition of how an image file's data should be represented in colour by any software handling the file.
There are three commonly used colourspaces; ProPhoto RGB, AdobeRGB and sRGB.  

Custom profile

A profile created specific to one particular device. Eg a printer, camera, monitor or scanner.
 

Gamut

The range of values that a given device can display. A wide gamut will display a greater range of colours, a narrow gamut has fewer possible values. If a device is unable to accurately reproduce a specific colour or tone, that colour, or range of colours, is said to be "out of gamut"
 
 

Gloss differential

A problem with certain types of ink and certain types of paper. The ink sits on the surface of the paper and has a different reflectivity to the paper, so has a duller finish. This primarily affects pigment inks on gloss papers.
 

ICC

International colour consortium. Also used as the file suffix to denote a colour profile.
 

ICM

Also used as the file suffix to denote a colour profile.
 

Metamerism

With inkjet prints, this generally refers to an effect where tones appear to change colour in different lighting conditions. Mostly noticeable with black and white prints made with coloured inksets, some tones that appear neutral when viewed under one light source will show a colour cast when viewed in a different light, e.g. daylight to tungsten light.
 

Profile

This is a file that converts colour values in an image file to correct for the characteristics of a device handling the file.
These files usually have the suffix .icm or .icc and are kept in a special folder on the computer.
 

Proofing

When an image is either printed out to check its quality, known as hard proofing; or when previewed on a monitor to simulate its final output, known as soft proofing.
 

Rendering intent

This option controls how colours that can't be printed (are out of gamut) are converted to colours than can be printed.
 

Spectrophotometer

A device that accurately measures colour, either by transmission from a monitor screen or reflected from a printout.
 

Workflow

The series of actions performed on a file from creation to final output.