COLOURS
SPOT Colours
When choosing different colours for your job, try to choose colours from the Pantone© colour palette if your software has it. If the job you require is to be printed in process, make sure these colours are converted to their CMYK equivalent. If your job is to be printed with a spot colour, check to make sure you have just one version of the spot colour. Some packages will have a CV or a CVC version of the same colour. A good way to check how many colours you have in your document is to print separations on your desktop printer. If you have more than the required no of sheets out of the printer you have too many colours.
RGB to CMYK
Your scanner, digital camera, computer and monitor use a combination of three colours: Red, Green and Blue (RGB) to create images.
The printing process uses four colours to print the same images: Cyan (light blue), Magenta (cerise), Yellow and Black (key colour), commonly referred to as CMYK or process colours.
At some stage the production workflow all RGB images have to be converted to CMYK.
The conversion from RGB images to CMYK should be done before the file is sent to us in an image manipulation package like Photoshop. If this conversion is not done there is a danger that the standard RGB to CMYK conversion profile we use may make some of the colours appear to be washed out or dull.
BLACK is BLACK?
You may not realise, but a lot can be done with black to help you to achieve the desired results.
To get the best from our process, black can be produced in two ways. The first method is single colour black, made from 100% black ink. This is ideal for small areas such as text.On larger areas of black solid single colour black can often appear grey or washed out. The way to achieve a dense black on large areas of black solid is to print a 40% Cyan underneath the 100% Black. This will give an even and dense colour as the second colour disguises any inconsistencies.
SET-OFF
Set-off is the marking of the underside of a sheet by the transfer of ink from the sheet on which it lays. It can occur when pressure is applied during guillotining or simply while the paper is stacked. Set-off is caused by the fact that the ink is still wet, and is most prevalent on uncoated stocks.
Set-off shouldn’t happen if you are careful about the weight of colours you pick.
We have set some guidelines to help you avoid set-off or lengthy drying times. Our recommended ink coverage limit is 225%. This means that, wherever possible, the colours you use should contain less than a total of 225% when you add together cyan, magenta, yellow and black.