Generating CTP correction curves based on linear plates
This page describes how to generate a CTP curve from linear plates. If you need to fine tune an existing CTP correction curve (‘curve-on-curve’) look here: generate CTP correction curves based on existing plate curves
What you need:
- MeasureColor Basic or higher license level
- MeasureColor CTP combi color bar eci_grayconm_i1_fogra39.pdf
- A compliant measurement device (X-Rite EyeOne, X-Rite eXact, Konica-Minolta MYIRO, Techkon SpectroDens, Techkon SpectroJet (Measurement devices like the XRite Intellitrax and Techkon SpectroDrive are less suited for this task)
- Embed the ‘MeasureColor CTP combi’ color bar in a test form or production job, make sure it is aligned vertically (printing direction)
- Generate the printing plates, and check linearity with a plate measurement device
- Print the form according to your standard for solid inks
- Let the printed sheet dry if applicable
- Open the ‘ProcessControl Module’
- Create a new job based on the proper reference. select a non-G7 Tolerance set and make sure the ‘MeasureColor CTP combi’ color bar is selected for this job
- Measure the color bar and hit ‘Finish’
- Analyze the result in the ‘Gamut’ view and check if the solids and overprint values match the chosen standard
- Analyze the result in the ‘Dot gain’ view and check that there are no odd results. TVI curves should look natural but might be too high or too low.
- If printed solids and overprint are OK and the (linear printed) TVI curves show no strange behaviors, it is time to generate the actual CTP compensation curve
- Switch to the ‘CTP’ view. This is where we analyze the printed curves and (automatically) calculate CTP corrections.
- To save a CTP correction curve in a native format, click on the ‘Save curve’ button
- Set the file name and location and choose the format for your workflow: Agfa Apogee, Caldera RIP, Fuji XMF, GMG ColorServer, Kodak Harmony (Prinergy), or Screen Trueflow
- Save the file to disk
You can now import the CTP curve in your Prepress system. To check the results, perform a standard quality check as described in the QuickStart document analyzing print quality.
If needed, you can fine-tune your current CTP curve as described in the QuickStart document generate CTP correction curves based on existing plate curves