INKS & COLOURS

When it comes to printing, this is the main focus from the printer’s point of view.

It is also the least understood area when it comes to the customer’s point of view.

Colour Management is both an art and a science that involves controlling how colours in a digital file such as a PDF come out in the finished printed product. There will always be a variation to some degree and how colours appear to one person can be completely different to another person’s perception. It is a tricky business and there can be many disagreements as to what is acceptable and what is not. This is the ‘art’ part of the business.

The technical ‘science’ part involves using ‘numbers’ or ‘colour values’. There are processes in colour management called Colour Profiles that allow the ‘input’ data to be converted to ‘output’ data via an algorithm which produces consistent results every time.

This works perfectly in theory but it assumes that the actual machines and inks do what they are supposed to do. With such variables in the printing process such as outside temperature, air humidity, differences in the whiteness of stocks, the lighting luminosity when viewing the finished product, and of course humans themselves being part of the process, there is a large possibility that something may cause change. This is part of the challenge of getting colour ‘right’.

Of course, the technology has improved so much in recent years that many of the variables can be managed. Colour profiles can be set up for each particular stock, machines are now automated to remove the ‘human’ element whilst the temperature, humidity, and lighting environment are controlled by working within contained spaces. All of this results in predictable results.

However, sometimes the finished results will be close but ‘not quite there’ and this is due to the limitations of the Inks or toners themselves. A range of colours is called a ‘gamut’ and depending on what the desired colour is, it may not be within the particular colour gamut. The RGB gamut has many more colours than the CMYK gamut.

For more information, read our sections on Colour Management and Inks.