There has never been more pressure on offset productivity and efficiency than now. Print runs are continuing to get shorter – customers demanding faster job turnaround times – which translates to more make readies and reduced profit margins. There is no question that if you have made an investment in auto scanning hardware system you are already ahead of the game. But are you getting the most out of it?

There are a number of parts or components to a closed loop colour control system and it is the sum of all these elements that really decides how much money you save by reducing your make ready costs.

To start let’s look into the elements that make up a viable closed loop control system:

Ink Pre-Set software – This is the software that usually takes a ‘CIP’ file that has been created by your CtP RIP. The CIP file contains the ink coverage information for each separation (CMYK + spots) and the ink preset software converts the data to ink key and sweep settings for each unit on the press.

Auto Scanning Spectrophotometer – This is the physical hardware component – the actual scanning instrument that scans and measures the colour bar (CB) patches from the printed sheet. Usually configured on the press console – aligned with the CB and automatically scans measuring each patch for each ink zone or key.

• Ink Pre-Set software – This is the software that usually takes a ‘CIP’ file that has been created by your CtP RIP. The CIP file contains the ink coverage information for each separation (CMYK + spots) and the ink preset software converts the data to ink key and sweep settings for each unit on the press.
  
• Auto Scanning Spectrophotometer – This is the physical hardware component – the actual scanning instrument that scans and measures the colour bar (CB) patches from the printed sheet. Usually configured on the press console – aligned with the CB and automatically scans measuring each patch for each ink zone or key.
  
• Computer Control and Interface to the Press – A computer platform is required (usually Windows PC), with a combination of sophisticated software and hardware to connect with the press console.
  Press manufacturers use different ways and protocols to interface or communicate with the press console – it could be a DPI (direct press interface) or a disk drive or via LAN (local area network) or even special hardware that emulates a memory type card. There is usually a way to communicate and interface with every press console available.
  
• Press manufacturers use different ways and protocols to interface or communicate with the press console – it could be a DPI (direct press interface) or a disk drive or via LAN (local area network) or even special hardware that emulates a memory type card. There is usually a way to communicate and interface with every press console available.
  
  
  

How does it all work? First the operator chooses the designated job with the ink pre-set data and sends that data to the press console. The software also manages the measurement instrument and displays the scanned data in an easy to follow and understand format. Ink key correction data can then be sent to the press. This is closed loop colour control in a ‘sense’ as you are adjusting the printed result based on the scanned measurements, making automated ink key adjustments and then the process is repeated to correct and maintain the desired evenness and colour. And yes, we are saying closed loop in a ‘sense’ as there is more that can be done to completely close the loop!

The initial ink key setting may not be in tune with how you are running the press for production. Fine tuning of the incoming ink pre-set data is required over time so the press can achieve the desired printed colour faster with each start up and make ready. Depending on your kind of work this can be completed relatively quickly – sometimes within days and weeks when new closed loop goes in. How is it done? When each production job is finished the ink key settings are recorded and then over time this can be compared to the initial ink key pre-set data. The ink ‘profile’ can be fine-tuned and adjusted for each process and spot so that the initial ink pre-set is closer and closer to the optimum settings for how the press is run for continued and successful production. This translates to much faster make ready for each job. Closing this final and strategic loop can get you to 95% or better on being at the correct production quality level.

Now consider the savings over time – with a completely closed loop system you can reduce make ready from thousands and many hundreds of sheets down to a 100-200 sheets. Doesn’t sound like a lot – over time it can add up to a lot of savings when applied to every job on the press.

There additional benefits of closed loop as well. Targets and standards can be maintained easily from within the system – reprints can be achieved, with less hassle to the previous colour as the job is saved with all the ink settings. The press operator will have more time to ensure the print quality is up to scratch – registration spot on – hickeys and other defects that can occur from time to time will be picked up.

The return on investment can be faster than you think, often within 6 months. Colour is a very important part of overall print quality, but if you can get it right, every time, you will move to be being a more successful profitable company – saving money on each job is the power of complete closed loop control.

To find out more about print quality management and printer colour management colour management please contact us via our contact form

An ICC profile by itself by itself does nothing, it is simply a colour description waiting to be used. You need at least two profiles to achieve an outcome. Profiles only work in a transform or conversion – you need a source and a destination profile. e.g. a source profile could be “sRGB” and the destination a CMYK print profile. This means the RGB file with the assigned sRGB profile will be converted to the CMYK space of the destination profile, under the control of the chosen rendering intent – Saturation, Perceptual or Colorimetric. Profiles communicate with each other in a common language, such as “L*a*b*” or “XYZ”.

An ICC profile gives meaning to the RGB or CMYK numbers in a file. For example, a scanner captures RGB information. The scanner RGB ICC profile provides meaning to how the scanner behaves and captures the RGB colour. The profile does not correct how the scanner captures colour it simply describes how the colour is captured. Now if you wanted to display the scanned image correctly you would need to make a monitor ICC profile. Profiles always work in twos!

We have oversimplified it a bit here, as colour management can be complex, but all you have you to do is follow some rules.

C stands for?

Before building a new ICC profile for a scanner, camera, monitor or printer you should calibrate the device first.

Calibrating is the most important step before creating an ICC profile. Calibration is about getting your device into a known, quantifiable and repeatable state.

What does this mean? On a monitor you adjust the brightness and RGB controls until you hit predetermined luminance and colour temperature targets. On an inkjet printer outputting through a RIP, calibration means setting up per channel ink limits, overprint ink limits, CMYK linearisation and grey balance control – it’s about ink media compatibility. Both aforementioned required measurement with an instrument (colorimeter or spectrophotometer) which makes it quantifiable. And if it is quantifiable, then it is repeatable.

After your calibration is complete you can then create your ICC profile.

If your device changes or wanders over time you can re-calibrate it back to the known settings and your existing profile will still be valid.
This is the benefit of having a good calibration process in place.

Every device is unique

Every device colour behavior is going to be different, which is why calibration is so important. Especially if you have multiple devices that you want to simulate to a common output colour space – think ISO Coated v2 (Fogra 39) or PSO Coated v3 (Fogra 51).

Every device colour behavior is going to be different, which is why calibration is so important. Especially if you have multiple devices that you want to simulate to a common output colour space – think ISO Coated v2 (Fogra 39) or PSO Coated v3 (Fogra 51).

Colour management is not perfect – there are device and colour limitations. And sometimes our expectations are set unrealistically too high. Colour measurement, human vision and viewing conditions all need to be properly defined, described and explained.

To realise the full benefits of printer colour management and setting up print quality management please contact us via our contact form

If you desire good colour management from your printer, you need to start with printer calibration. When we talk about printers, we mean inkjet, solvent, UV, toner or liquid ink-based print devices or print engines – basically, the vast majority of printing machines! Colour management 101 (our stock in trade) dictates that we should pay very close attention to printer calibration.

So – what is it, and why should you care?

Calibration is best described as the process of bringing a colour device (printer, scanner, monitor) into an optimal, quantifiable, repeatable state.

• Optimal: The best result obtained or obtainable under specific conditions.
• Quantifiable: Capable of being measured, which means it then should be…
• Repeatable!
  

Printer calibration could involve getting the printer could conform to an established industry standard (such as ISO 12647-2 for print) or a manufacturing standard/guideline or even your own specification.

Printer calibration enables you to keep track of “device drift”. Over time, even with consistent use of the same consumables (ink, toner, paper), your printer will suffer from device drift. We calibrate to make the printer behave consistently and bring it back into a repeatable state. This enables colour management to remain valid and accurate.

Printer calibration is best thought of as the first step of the colour management process. The second would be printer profiling or print ICC profiling.

Printer profiling is sometimes called characterisation – the process of recording a device’s behavior into a profile. It is simply a record or map of how the device produces colour – what it is capable of producing. This record (referred to as an ICC profile) will show you the device’s gamut (i.e. what colours it can and cannot print), reflected by the calibration process.

Printer calibration can be likened to having your car ‘dyno’ tuned for optimal performance.

Printer profiling can be likened to getting a report of your car’s ‘dyno’ tuned results – power output, torque, and so on.

Print calibration is like money in the bank – when you find your print colour has drifted, print re-calibration, back to the same targets, will enable your existing print ICC profile to be valid again – i.e. your colour will be back to where it should be!

How often should you re-calibrate? That can depend on your print device, and it is well worth taking the time to set up process controls to monitor and gauge device stability. Sometimes though, a certain amount of drift or instability may need to be accepted.

A small note: Some print devices cannot be calibrated – for example if the device is a non-Postscript printer and/or does not have a ‘RIP’ that usually includes some calibration tools. 

Colour Graphic Services can help you to do all this and more! Contact us to learn more about our cost-effective, stress-free solutions via our contact form

I often get asked where to start when setting up a CMS (colour management system). Well, not one answer fits all. Like a lot of things there is ‘ifs’ and ‘buts’.

It depends on a few things. i.e.

• What is your colour workflow?
  RGB or CMYK?
  Or both?
• What is your final output?
  RGB photo print output?
  CMYK digital or wide format print?
  Offset CMYK print?
• What are your requirements?
  Soft proofing – or just a colour calibrated monitor?
  Accurate colour from printing? (RGB photo print or CMYK digital or offset printing) Correct set up of colour conversions or transforms? (RGB to CMYK, etc)

Well, the answers can be many and varied, so I will try to provide the Top 10 Colour Management tips that can be applied in general.

1. Check your printed results under the right light – JUST Normlicht LED D50Yes, okay – I am recommending a manufacturers product – JUST Normlicht LED D50, DLS (Digital Lighting System) – They can be considered globally unique and there patented LE systems are the best for ISO 3664:2025!
   The correct lighting for viewing printed results* is absolutely critical and that is D50. What is D50? Daylight at 5000K. The standard for viewing printed results* for photography, graphic arts, prepress and printing (digital, offset or otherwise) is D50, straight from ISO 3664:2025. *Printed Results = Photo prints, Fine Art prints, PrePress digital proofs, Commercial printed matter from Digital Production machines, Wide Format digital, Offset, Flexo, Gravure and the like.
   NOTE: Just because a bulb or tubes or LED is 5000K does not automatically mean it is D50!Using the correct D50 lighting in your CMS is often the easiest, sometimes the cheapest thing to fix and implement – it is also the most IMPORTANT part of a CMS. Unfortunately, though, it is also the most forgotten and overlooked part…
   
   
2. Make sure you get the best monitor possible
   By this I mean the best monitor you can afford, and then some… If you rely on your monitor for accurate visual colour assessment then you should think about getting a monitor that can provide a good/wide colour gamut, smooth/even tonal gradations, good uniformity and even screen brightness across the display and one that can be easily calibrated.
   Cheaper monitors are ok for email, writing up text documents, playing games or maybe watching an occasional video – but if you are serious about colour you should invest in the best monitor you can afford, and then som
   
   
3. Learn and know how to calibrate your monitor
   Monitor colour calibration requires the use of a measurement device – a colorimeter or spectrophotometer, software and then adjustment of the monitors controls (usually through the OSD – on screen display) to achieve the desired calibrated result.
   There are also very good monitors that have built in measurement devices, and these can automate the calibration process.
   Importantly, you need to know the targets for calibrating your monitor to suit your workflow and process – i.e.  photographer, designer, retoucher, prepress/printing…
   
   
4. Keep your monitor calibration up to date and verify the calibration
   Most good quality monitor colour calibration ‘systems‘ will allow you to run a monitor calibration verification/validation routine, also called a QA check.
   If your monitor passes the verification/validation routine – i.e. it is within the tolerances, then you can keep working without having to re-calibrate. Do this at a minimum once per week. If the verification/validation fails, time to re-calibrate.
   
   
5. Gain skills and knowledge about Colour Spaces, Gamuts and ICC Profiles
   There are limitations in any CMS because of the devices being used and improving your skills and knowledge can be time well spent. This can be done by tutorials, reading or even better, one on one training from a reliable colour consultant! Getting educated with some good colour management training can go a long way to de-mystifying what you think you know and what actually is the truth.
   
    
6. Ensure you have the right settings in your software
   This a big one! Whether you are a photographer going from capture to print, graphic designer, retoucher, working in prepress, getting files ready for Digital Production print, Wide Format digital print, Offset, Flexo or Gravure. You need to know and fully understand the colour management settings in software you are using. Colour standards, colour spaces, ICC profiles, rendering intents are key points here…
   
   
7. Are your colour measurement instruments okay?
   The densitometers, colorimeters, spectrophotometers you are using – are they up to date for certification and calibration? Do you have an in-house validation system in place for the instruments? Accurate, repeatable and validated instruments can provide you measurements you can trust.  
   
   
8. Have you got procedures in place for colour verification?  
   Are you able to verify the colour output on your monitor? The colour captured by your scanner? The colour output through your print process or print system? Can you verify the accuracy of your soft proofing and digital proofing?
   
   
9. Do you know how to perform printer colour calibration?
   Printer colour calibration is the key to maintaining accurate, consistent and repeatable colour from your print process or print system. This applies to RGB photo print, CMYK digital and/or wide format print and commercial offset, flexo, gravure print.
   
   
10. What are the variables in your CMS? What control do you have over them?
    There can be many variables in a CMS and some may be out of your control. i.e. The effect of ambient light or factory/office lighting on visual assessment of colour printed results may be out of your control or may not be able to be changed…
    You need to get to know your instruments, software, devices really well – the more you know the more you will understand about the capabilities and limitations of your CMS and process.
    
    

Contact us to learn more about our colour management training, cost-effective, stress-free solutions via our contact form