Colour Standards play a crucial role in ensuring accurate and consistent reproduction of a colour in the printing environment. This maybe a colour or range of colours that is printed as a digital proof or on any output device digital or traditional printing. A colour standard not only assists the converter in meeting the EXPECTATIONS of their customer, the brand-owner, but also clarifies what is ACHIEVABLE. All too often printers/converters find themselves in a position of trying to meet a customer’s requirements (Expectations), but do not know what the target or goal is. Not only does this make the task of reproducing the colours accurately impossible, but no one in the print workflow knows what the final results should be! With proper colour standards, the converter knows exactly what the targets are and what the brand-owner expects.With proper colour standards, the converter can ensure the ink supplier provides the correct colour ink and the brand-owner no longer has to do press sign-offs of work..This ensures higher production levels, lower waste and better productivity.
Colour standards can either be a physical sample with measurement specifications or an electronic data file, such as CxF (Color Exchange Format), which contains all the relevant information.
When printing to targets or standards, proper process control and measurement is central to the process and that of meeting the end results.
Why do we need Colour Standards?
- Accurate and consistent reproduction of a colour
- Specify a colour and/or brand
- Manage expectations of the brand
- Clarify what is achievable
- Meet the Quality Assurance standards
- Compliance to a standard or target
- Ensure the customer gets what he wants
What should a Colour Standard contain?
- Colour Description
- Definition or description of the colour
- Sample - any of or all these for physical samples
- Digital reproduction - certified
- Printed sheet - approved by customer
- Ink drawdown sample
- Instrument type
- Measurement conditions
- LAB/LCH values
- Spectral Data - CxF version (electronic)
- Validation period / expiry date (physical only)
Question: Who supplies or is responsible for the Colour Standards?
Answer: Quite simply, it is the responsibility of the Brand-owner to ensure they provide the converter/printer with the correct colour standards and information. If the brand-owners does not have colour standards, the converter must understand the risks involved in taking on the job.
Q: What should the converter/printer do if there no colour standards?
A: The converter should recommend the brand-owner gets professional colour consultants to assist them with setting up their colour standards and specifications or they can offer to facilitate the process. There are also other solutions, such as PantoneLive, that can be implemented.
Q: What is an acceptable tolerance for spot colours?
A: The tolerance or DeltaE depends on the print process, however, a value of 2.5 DeltaE 2000 is generally accepted. The SOP ( Standard Operating Procedure) may also contain a table which has recommendations as to adjustments or processes to apply if the DE is above 2.5.
Q: What is CxF?
CxF stands for Color Exchange Format, which is the industry and ISO standard file format for colour data. A CxF file may contain values such as the Colour or colours names, Spectral data, colour space values (L*a*b*, LCH, RGB), DeltaE tolerances, as well as the type of instrument or software used to create the data plus the measurement specifications. CxF data can easily be transferred between devices and software, or sent between the brand-owner, converter/printer, ink-supplier & QC.
Q: Which format is better for a colour standard: physical or CxF ( electronic)?
A: CxF data is better as it can easily be loaded onto measurement instruments or setup on the print workflow and process control. It will also not get outdated, fade nor risk of being damaged. Physical standards on the other hand have a limited validity period and is subject to environmental issues.
Q: Can we use the Pantone guide for colour standards?
A: The Pantone guide is just that, a guide, and NOT a colour standard. Pantone Guides are litho printed on specific substrates to be used as a visual tool for choosing colors during the design process. Thereafter the Pantone colours need to be adjusted to match the output print process and substrate, so these well not become custom colour standards.
Q: My customer uses Pantone 485C as their brand colour?
A: This is a common practise, but as P485C is adjusted to meet the output process it is no longer P485C, but rather a dependent colour and hence a new custom colour or standard. This be colour should be measured with a spectrophotometer and the colour data saved in CxF as the brand-owners new colour standard. Many converters have 10s of different P485C “colour standards” and associated inks. Each of these dependent colours should be saved as the relevant brand-owner’s custom colour standard.