We often get asked "just come in and profile my printer". But, it is very rare that we make just a profile only.
Calibration is required first, and this applies for all devices - scanner, camera, monitor and printer.
What is Calibration?
It is about getting the device into an optimal, quantifiable and repeatable state.
For printer colour calibration, getting into an optimal state, means adjusting the ink/media settings so that you are not over inking - looking after per channel ink limits and overprint ink limits. Also, getting the tonality right. i.e. a smooth graduation of tones as evidenced by the print out of 5% or 10% increments on a step wedge. And even getting the 'grey balance' right, if that is possible.
The calibration should be quantifiable. This means it is measurable - with an instrument like a spectrophotometer.
And if it is measurable, then it will be repeatable
This is especially important.
As your printer 'drifts' through time, with wear and tear on parts and usage, redoing the calibration can bring your printer back to the optional, quantifiable and repeatable that had been established.
How do I know, and how can I get my printer into an optimal, quantifiable and repeatable state?
Well, first you need to find out and know as much as possible about your printer, the inks, the media (substrate) and your RIP software. Study the on line guides or instructions, do print tests, seek out advice... You may find it beneficial to have some printer calibration training. Once you have the skills and knowledge required you will have confidence to maintain and complete printer colour calibration yourself.
What about Monitor Calibration?
This is an example where calibration and profiling are 'linked'. You usually do not just profile a monitor - it has to be calibrated first. What white point point (colour temperature), what luminance, gamma, black point, etc? These are all part of calibrating your monitor before the profile is created. Think about it. The measurement of patches for creating and building the monitor profile is only possible after calibration.
Digital colour management is only possible after completing the calibration of each of your devices in your workflow.
What about ICC Profiling?
Once your device is calibrated the next step is ICC profiling.
For printers this will mean outputting (printing) a profile chart, measuring the chart and building the profile. If your calibration is good, the printed chart should not have any 'wet' ink patches, etc. You will require a good spectrophotometer and profiling software package to complete this task. Although many printer RIP's now include the option of creating ICC profiles - you will still need a spectrophotometer.
What settings to use when building your profile and then validating your profile are important final steps.
Building a profile using sometimes default software settings can seem easy, but it may not be correct for your particular purpose, your printers ink set.
- Is the print profile going to be used for RGB to CMYK conversion?
- Or is it only going to be used within the printer RIP for digital prints or proofs?
How you answer these two questions can have a significant bearing on the profile settings...
Building profiles can be relatively easy. Building a good profile, that can be validated is more difficult...
By validation, I mean checking and confirming your profile is OK to use - no strange results when converting, no artifacts, are all the rendering intents ok to use? The methodology used for these steps is very important, suffice to say this blog is not really about the detailed steps to take (there not enough space or time here).
For successful colour management one of the key ingredients is calibration and profiling of your devices.
- Printer colour management requires printer colour calibration
- Good monitor soft proofing requires correct monitor calibration, profiling and a high quality monitor, with attention to the ambient lighting and surroundings.
For more information on colour management training and the full range of Techkon measurement instruments contact us at info@colourgraphicservices.com
