Troubleshooting Color: Media Parameter Setup

More than once I have been asked: "OK, so the color is wrong, how do I make it right?"

Troubleshooting CMYK color can be a pain, because there are often many places the problem could be lurking, and changes made in one, may inadvertently alter the output based on info from another. So in this five part series, we will look at five important steps to troubleshooting a color managed system, or colorimetric tuning.

As you all know, a color management system is usually broken into five parts:

1. Source color space
2. Media parameter setup
3. Source color space designation
4. Output color profile
5. Output calibration set

Part 2 - Media Parameter Setup

There are many different kinds of paper, such as recycled and rag paper for newspapers, glossy coated paper for magazines, uncoated paper for stationary and bright-white coated paper for high-quality brochures. Some paper is coated for a particular ink, some has already been printed on (shells) and some is in fact black, or darkly opaque for printing on a 5th color station press, using white toner. And now synthetics have become a hot trend in digital printing.

As you can imagine, each type has different characteristics when it comes to printing. The recycled paper sucks up more ink, and if you don’t take this into account, your beautiful full-color photos will become too dark, and the ink will blur over the paper, creating an ugly brownish effect. Coated paper reflects light differently, and distinction between matte & gloss can make a LOT of difference to the final colors.

So, how do you optimize artwork for all of these different kinds of papers? Well, that’s the easy part. 

Standard CMYK inks have been tested on every type of paper imaginable. The way cyan, magenta, yellow and black are printed on a specific type of paper is documented in an ICC profile (a complete record of a print device's color gamut). All you need to do is download these free “Color Profiles” and select the right one when you export a PDF using InDesign (Export → Output → Color Conversion & Destination). 

In Photoshop you can use these profiles as input profiles, to soft-proof colors printed on specific stock.

To learn more about profiling, read Calibration and Profiling

The RIP's job parameters related to media setup and imaging style must be consistent for the customer’s job, as well as for the related profile generation and calibration pages. 

A specific determining factor is Fuser temperature: Higher fuser temperature results in increases in gloss and density.

The primary specification for fuser temperature is Paper Weight, with a lesser degree of control through paper type (Plain, Glossy, Matte). Fuser Nip (dwell) and direct Fuser Temperature setting in the paper catalog entry also have an effect on fuser temperature.

Halftone Mode: Also known as screening type. Specifies whether line or dot screening is used, and in
some print devices, the halftone resolution (lpi) and native resolution (600 or 1200).

Resolution: Effective pixel addressability, collected pixel size and gray tone possibilities. May be
specified combined with Halftone Mode.

These job properties must be decided upon prior to any further color tuning, and used for all customer
jobs, calibration sheets and profile targets for the applicable job/media setup. Of course, any given
machine and customer may use one or more job/media setup with varying parameters.

Any adjustments determined in Print Engine Setup should be applied via SP mode and/or a paper
catalog entry and used for all applicable prints.

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Do you have a color management question, horror story or event to share?

Email me at reilley4color@gmail.com