DEFINING COLOURS

When defining colours, you must refer to a printed tint guide before entering values in the colour palette. That’s because RGB colour monitors do not accurately represent ink on paper – whether CMYK process tints or PANTONE^® spot colours. Many desktop programs allow you to specify colours in two ways:

as spot colours by product name (such as PANTONE)

as process colour by setting CMYK percentages

COLOUR MATCH

Every colour printer interprets colour values differently, therefore we will assume that your supplied proof is for content and pleasing colour reference only. If you require your final printed product to match your printed proof, colour correction to your files may be necessary. Please contact your customer service representative for a quote for this service.

PROCESS COLOURS

If elements of your book are going to be printed as a four-colour process, “process separation” must be selected when you create a new colour. If you don’t select this option, the colour will be created as a fifth “spot” colour in the job.

SPOT COLOURS

When specifying spot colours, make sure that they are set to separate as Spot and not as Process. This is the most common error encountered when defining spot colours, especially in EPS files.

CHANGING SPOT COLOURS TO PROCESS EQUIVALENTS

When specifying process tint matches, be aware that different programs can generate different CMYK percentages for the same PANTONE colour. Some software developers have ignored the recommended PANTONE CMYK process tint percentages and have substituted their own. We recommend using a PANTONE swatch book for selecting and matching colours. The PANTONE Matching System (PMS^®) is the North American standard for colour specification.

RGB OR SPOT COLOUR CONVERSION TO CMYK

If files are received containing RGB or Spot Colours for a product printing in CMYK, the colour conversion can be performed automatically by our RIP, however the outcome may not meet expectations. It is best to either perform a colour conversion before file submission, or request a quote for this service from your customer service representative.

NAMING CONVENTIONS

The naming of colours is important because a printing plate is output for each colour listed in a palette (CMYK and any spot colours) used in a document. For instance, using the colour “Spot Black” or “Pantone Black” instead of just “Black” will result in two separate plates. Colour names must also be consistent among applications. If one of your applications uses a slightly different naming convention for its colours (i.e. PMS 335 CVC vs. PMS 335 CV), two different plates will be imaged when the files are processed, even though the colours themselves match.

Colour naming must be consistent among applications.