Colour

Colour CMYK RGB Elements Pantone/Spot colour Half-tones

Magenta

CMYK

Colour in print provides dynamism to a design, attracting the attention of the viewer, and sometimes bringing out an emotional response.

CMYK is subtractive colour, when you subtract cyan, magenta and yellow, it gives you black (key). Where two subtractive primaries overlap, only one additive primary is visible. Blue is formed where cyan and magenta overlap. Cyan and yellow overlap to produce green. Magenta and yellow combine to form red. Where all three subtractive colours overlap, black is produced because no light escapes.

Key

CMYK is used in colour printing, and is also used to describe the printing process itself. It varies by different print houses, press operators, press manufacturers, and press runs, but the ink is typically applied in the order of the abbreviation, CMYK. When printing a document, make sure the document is set up in CMYK colour mode as RGB is an on-screen mode and CMYK is physically printed colour mode.

Yellow

Cyan

Red

RGB The main purpose of the RGB colour mode is for the on screen sensing, representation, and display of images in electronic systems, such as televisions and computers.

Although different devices reproduce a certain RGB value differently, since the colour elements and their response to the individual R, G, and B levels vary from manufacturer to manufacturer, or even vary in the same device over time.

Therefore when working with RGB, consider that it doesn’t detect the same colour across devices without some kind of colour management.

RGB is a additive colour code therefore, where red and green overlap, yellow is created. Magenta is formed where red and blue overlap, and cyan is created where blue and green overlap. These secondary colours are the subtractive primaries.

Each additive primary represents a component of white light, so where all colours overlap, white is produced.

Blue

Green

Elements

Hue

Hue, saturation and brightness are three colour elements that can be manipulated to change the appearance of an image.

Altering the colours on an image now is straightforward by using software such as Photoshop.

Hue Hue, refers to the unique characteristic of a colour that helps us visually distinguish one colour from another. Hues are formed by different wavelengths of light.

Saturation Saturation refers to the purity of a colour and saturation levels describe a colour’s tendency to move towards or away from grey.

Brightness Brightness refers to how light or dark a colour is. Changes in the brightness value can be achieved by mixing a colour with black or white.

Saturation

Brightness

Pantone

The Pantone colour system has developed to include a wide range of different colours, which has a system that allocates a unique reference number to each hue and shade to facilitate communication between designers and printers. There are different Pantone books and references for different stocks, e.g.

Uncoated, Coated, Metallic, Matt.

Spot colour

Spot colours are made from various base element, mixed according to a specific recipe. Spot colour inks can be bought pre-mixed or can be mixed. Using spot colours in print is very useful as if a design is being printed commercially there will be less print plates used, rather than creating the colour from CMYK, spot colours only have one plate. This process can also have hindrances as it may cost more if you have CMYK plus a spot colour, as that is then using five print plates.

SPOT COLOURS Pantone DS 5-2C

Pantone DS 1-5C

Half-tones Halftone is the reprographic technique that simulates continuous tone imagery through the use of dots, varying either in size, in shape or in spacing, it does this by fooling the eye into thinking it is one continuous tone.

Where continuous tone imagery contains an infinite range of colours or greys, the halftone process reduces an image that is printed with only one colour of ink, in dots of differing size.

This reproduction relies on a basic optical illusion that these tiny halftone dots are blended into smooth tones by the human eye.

Colour printing uses separate plates that contain half-tone dots for different printing inks. A designer can manipulate these dots in order to change the appearance of the printed image.