Got colors that don’t match?
We Bring You Back From Chaos
- Color management
- Job management
- Automation and customization
- Prepress and printing standardization
About Color Management
The best way to look at a workflow is to consider every step of the way, from initial image to screen to desktop printer to prepress and production and to press. It’s a long road with specific areas of expertise along the way. No matter where you are in the chain, you would get an overall understanding of the whole process with deeper knowledge of your specific area.
Whether you’re a photographer, an artist, a designer, a retoucher, a production artist, a prepress operator, a printer, there’s a lot to find out. Photographers, for instance, grapple with whether to shoot in RAW format and whether to deliver RGB or CMYK files. How much retouching should they do? What’s the best way to communicate with the client? Ad agencies have always juggled fast and high volume printing with color accuracy. Is there a machine somewhere that will give them predictable color fast? Printers look for standards that will allow them to match a proof to their press, and a press to another press. Should they move to G7?
With evolving technology comes an endless supply of new questions. In our commitment to provide the best possible solution, we test RIPs, new software, papers, printers. If you’re curious about a specific RIP or printer, please give us a call.
Contact Erica Aitken – info@rodsandcones.com – (831) 421-0131
About Proofing
Proofing is a word that means a lot of different things. Softproofing for example, is finally available and so precise that press sheets are matched to monitors. Inkjet proofs can achieve a match of greater than 98% consistently and have become today’s contract proof. Some inkjet printers have sophisticated built-in color management including a spectrophotometer. And laser printers who could never produce accurate color consistently are finally reliable for fast, high-volume accurate prints.
On press, things move all the time. Standards are constantly questioned and new methods developed. Do you go with SWOP or with G7? Or both? Should you accept a file displayed on a monitor as a contract to match on press? Who decides what the standards will be and how do you make sure that your file is correctly printed?
About GRACoL7
1. What is the difference between GRACoL, GRACoL7, and G7?
- GRACoL is a set of specifications for commercial printing developed by the GRACoL committee, a member of IDEAlliance
- GRACoL7 is the latest version of these guidelines
- And G7 is the methodology used to meet these specifications
2. What is a traditional press standard based on?
- SID (Solid Ink Density)
- TVI (Tone Value Increase or Dot Gain)
- Wet ink trap
- Print Contrast
3. What are the limitations of traditional press control?
- SID specifications do not reflect an individual press’ capability
- TVI is set to different values for different printing processes (i.e. sheetfed, web, newsprint)
- TVI and SID do not define the appearance of color on press
4. What are the advantages of the G7 method?
- G7 measures substrates and colorants using colorimetry rather than density
- It uses gray balance as the primary control measurement
- It establishes a Neutral Print Density Curve (NPDC) as a target for the reproduction of highlights and shadows
- Although they remain important metrics, SID and TVI are no longer the primary process controls
5. Why is Gray Balance important in evaluating a press sheet?
Because when neutrality is defined and maintained, color will usually look correct and stay consistent through a press run
6. Why is it better to use colorimetry than density?
- Because colorimetry considers color and color balance rather than the weight of ink on paper
- And because it gives the ability to define the appearance of color and to monitor color change
7. What is a Neutral Print Density Curve (NPDC)?
- NPDC is a target curve defined along the entire tonal range. GRACoL7 defines a specific NPDC curve that allows the press to run to its natural tendencies, using plate compensation curves to correct for unwanted behavior.
- It uses the entire tonal range not just the traditional TVI 25%, 50%, and 75% values, giving you the entire shape of a curve, from highlight to shadow
8. How is Highlight Range (HR) used for process control?
- As a quick check to visually compare a 50/40/40 CMY patch to a 50K patch
- As an additional checkpoint, to check gray balance in the 50/40/40 CMY patch
- And to monitor the TVI of the press run
9. What are the benefits of the G7 method? They are:
- Faster make-readies because the press operator can quickly determine the ink balance on the sheet using neutral and black patches
- Better control on press because G7 uses colorimetry
- Gray-balanced plate curves improves the press’ ability to print neutral through the whole tonal range
10. Am I a good candidate to switch to G7?
- Yes, if your color make-ready is taking longer than you’d like
- And if you want to spend less time measuring press sheets
- Also if your customers complain about the quality and the consistency of your color
- Or if you need to match color appearance across multiple presses or press types.
How are different printing processes matched via G7?
(Written for Out of Chaos Magazine by Kevin O’Connor. Read the full article here)
G7’s success was so spectacular for GRACoL workflows, that G7 methods were tested on other workflows such as SWOP. Managing gray so carefully paid dividends in SWOP workflows and in other workflows as they were tested. Today, a series of printing conditions has been defined in a new standard, CGATS 21-2 (ISO PAS 15339). This family of print conditions, referred to as the CRPC1-7, has seven categories, each with its own reference data set. All of them share a visual appearance because they’re all based on G7 neutral gray appearance.
These seven sets are called:
ISO15339-CRPC1
Typical ColdsetNews – Small gamut printing (newsprint)
ISO15339-CRPC2
Typical HeatsetNews Moderate gamut printing on improved newsprint type paper
ISO15339-CRPC3
Typical PremUncoated Utility printing on a matte, uncoated type paper
ISO15339-CRPC4
Typical SuperCal General printing on super-calendared paper
ISO15339-CRPC5
Typical PubCoated Typical publication printing
ISO15339-CRPC6
Typical PremCoated Large gamut (typically commercial) printing
ISO15339-CRPC7
Typical Extra Large Extra-large gamut printing processes
In the map shown next page, the innermost outline shows the gamut outline for ISO15339-CRPC1, which defines color for a newspaper printed without heat-drying the inks. The rest grow outward, with ISO15339-CRPC7, an extra, extra large gamut process being the biggest. In the second image, comparing the biggest and smallest 3D versions, there’s quite a difference in total color printable, but applying G7 to both processes provides the best possible visual match for the two processes.
Rods and Cones: Perfect Color and Custom Workflows
We will get a match between monitor, printers and presses and we’ll make sure that your workflow is the most efficient in terms of time and cost. We can advise you on what printer is best for you, whether you need a RIP and which one, and if you would do better using the G7 method on press.
To get the most out of your resources, bring us in to evaluate your workflow. If in need of something more efficient, we’ll design a new workflow especially for you. Our proposal is backed by a ROI, technology, and the most seasoned workflow experts.
Contact Rods and Cones at (831) 421-0131 or email info@rodsandcones.com