Manual - basICColor GmbH · This manual only covers the basic operation of the ... precise calibration of CtP platesetters and presses ... Please refer to the basICColor catch manual

Manual

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basICColor catch calibrateBecause it simply works!

Index

1. Introduction ......................................................................................... 4

1.1 System Requirements, Installation and Licensing ..............................6

2. basICColor catch - Module: calibrate .................................................7

2.1. Preface..........................................................................................................8

2.2. Target Description .................................................................................. 10

2.3.Printing the calibration targets ............................................................12

2.4.Perform a calibration ..............................................................................15

2.5 Creating a TVI Correction........................................................................21

2.6 Example for Harlequin Report .............................................................24

2.7 Updating of Correction Data ................................................................28

3. Product Information basICColor calibrate .................................... 31

Chapter 1

Introduction

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1. IntroductionWith basICColor catch you have a universal and very flexi-ble application for measuring of linearisation, profiling, and quality assurance targets.

A variety of instruments and targets are supported.

In addition to the possibility of individual design of own distinct measurement processes, a wide range of important job templates are pre-configured.

This program structure is also the key to high productivity, which is open to you through the expansion with additional modules basICColor catch.

The basic version of basICColor catch allows to measure any color originals such as RGB or CMYK printer targets, but also the individual characterization of camera targets. To create an ICC profile for your printer basICColor catch creates ISO 12642 - compliant measurement files that you can use to calculate the ICC profile in basICColor print or other ISO-compliant ICC profilers.

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With the module basICColor calibrate you can check the dot gain (TVI) of a printing press. Furthermore basICColor calibrate serves for simple and precise calibration of CtP image and printing presses.

This manual only covers the basic operation of the module basICColor catch calibrate. For the use of the measureing application basICColor catch pro and modules basICColor control (QC color), basICColor certify (QCprint) and basICColor statistics (QC visual) please refer to the manual basICColor catch 5.

You can find a copy of the basICColor catch manual in the application folder of basICColor catch or you can download it from our website: http://www.basiccolor.de/user-manuals/

http://www.basiccolor.de/user-manuals/

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1.1 System Requirements, Installation and Licensing

For System Reqirements please refer to the product page on our website: http://www.basiccolor.de/basiccolor-catch-5-en

For installation and licensing process please refer to the Licensing user manual on our website: http://www.basicco-lor.de/user-manuals/

http://www.basiccolor.de/basiccolor-catch-5-en

http://www.basiccolor.de/basiccolor-catch-5-en



Chapter 2

basICColor catchModule: calibrate

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2.1. PrefaceThe module basICColor calibrate serves to check the dot gain (TVI) of a printing press and. Furthermore a simple and precise calibration of CtP platesetters and presses can be done. Optionally can be checked whether the printing press complies to the PSO specifications of the Print and Media Association (VDM). Also, with the use of basICColor calibrate dot gain curves can be created that can then be loaded in the Harlequin RIP for example. The calibration is based on a target with a gradient of the primary colors C, M, Y, K and on the measured spectral data of the primary colors of a printing machine. Therefore, a spectrophotometer, such as the EyeOne Pro by X-Rite is required.

Using basICColor calibrate either the entire workflow, i.e. imagesetter & printing machine, or just the dot gain of the printing press to the specifications of FOGRA or other stan-dards can be adjusted.By calibrating the entire workflow, the platesetter is not calibrated separately, but the printing plates or films are put out without calibration (i.e without correction) in the RIP. In the second variant, it is assumed that the platesetter outputs linear plates.

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In this case, the platesetter must be calibrated with a densi-tometer separately. Thus, basICColor calibrate can practically be used for all workflows .

Requirements for a successful calibration is both a techni-cally flawless functioning platesetter as well as a techni-cally flawless press. The developer unit on the imagesetter should be checked prior to its use. On the printing press the blankets should not too old and the mixture of water additives have to comply with the specifications .

There are two types of calibration targets available . The simple template contains only the gradients for CMYK . A slightly more elaborate template includes an example of color reduction in addition .

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2.2. Target DescriptionTo create your own template you can use the default target, Offset Lintarget Standard.pdf , which includes only the gra-dients in CMYK. This target should be installed in sufficient numbers on the sheet. Thus, the dot gain can be measured at various locations within a printed sheet. For calibration and PSO control the target established by the bvdm for the PSO-control can be used

The extended test form, Offset Calibration.pdf‚ contains various elements for the calibration and printing control. The images on the left side of the form were reduced in in-king with the basICColor Print Production Server and despite considerable savings of inks (CMY) do not lose the color in print. The pictures on the right side of the test form are left in their original state. This serves to illustrate the advan-tages of the color reduction in print. In the middle of the two groups is the target with the curves for calibration.

At the bottom are the fields for the control of gray balance during printing. These fields are available in three levels of brightness.

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Each control patch consists of two elements. The outer area is a pure black, the inner area is the corresponding CMY combination. It should be ensured that the outer area of the control patches K and the inner area CMY match in color. Below these elements there is a bar for color decline. The target is to be exposed on the printing plate, that the upper edge of the document is at the feeder of the printing press, so that the measuring fields are printed from light to dark.

For online control, the Online print control.pdf, is used. This target is based on the ECI target ECI_TVI_10_i1_v2.pdf ‚and has been modified in the length that it can be measured with the standard ruler of EyeOne. With a longer ruler the original target of the ECI can be used, which can then optio-nally can also be enlarged in lenght to fit the print sheet. In addition, the ECI_bvdm_Gray_Control_Strip targets can be used for on-line measurement

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2.3.Printing the calibration targetsBefore exposing the printing plates determine which way of calibrating you want to proceed with.Normally, the imagesetter and the press will be calibra-ted separately. Here, however, it must be ensured that the imagesetter calibrated printing plates are produced first.If it is not possible to calibrate the imagesetter, when polyes-ter printing plates are used for example, the calibration of the imagesetter is corrected together with the dot gain of the printing press.

Most imagesetter-RIPs offer two ways to correct the TVI.

One option is to set FOGRA defined density values as nominal values (intended Press) and then enter the values measured with basICColor calibrate as actual values (actual Press). The imagesetter-RIP then calculates the necessary correction for exposing the plates.

The other option is the creation of TVI correction with basICColor calibrate directly. Here, the result is saved into the imagesetter-RIP as target value (intended Press). The imagesetter RIP case does not make any corrections but exposes the plates to the basICColor calibrate calculated correction.

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To print, you need a densitometer to control the final den-sities. Generally, there‘s no set specification for final densi-ties. Unless you have your own specifications, the following values Paper type 1 & 2 (coated paper) can provide some guidance.Cyan 1.50 Magenta 1:45, Yellow 1.28 Black 1.85, measured with a densitometer with polarization filter. The values de-pend on the temperature of the printing press, the ink, the paper and the water management.

Measuring the final densities should always be done in the 100% patches of the targets. All four inks should be the same type and manufacturer. Optimal are PSO inks such as Van Son Quickson Pro for example. For the entire calibrati-on the same type of paper must be used always. For a run you need about 500-1000 arc depending on the accuracy of final densities. The test form should be printed on a warm printing press if possible. A cold printing press cannot deli-ver a reproducible result.

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Once you have achieved stable densities , print about 50 good sheets. Take them off the press and pull appx. 10 non consecutive sheets. Spread these sheets if possible and let them dry for about 30 min. Connect the measurement device to your computer, so it has the required operating temperature as soon as the printed sheets are ready for measuring .

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2.4.Perform a calibrationAs mentioned above, a spectrophotometer is required for measuring the target. Please ensure that the meter is turned on or connected to your computer appx. 15-30 min prior to measuring. Are the sheets dried sufficiently, start basICColor catch. Please refer to the basICColor catch manual on how to use the application (ie. creating a job, connect a measure-ment device, measure a target, etc.) and it‘s features.

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Start the measurement with the right column. Place the ruler on the measurement fields. Now put the meter above the first black line on the ruler. Start the measurement in accordance with the instructions of the instrument and pull the meter to below the last measurement field. Repeat the process with magenta, cyan and black. Are all column-measured, click the Icon „Measurement“ and start a „New Measurement“. Measure the next sheet. Proceed. Please ensure that a new measurement is openend for each new sheet before measuring.Once all sheets are measured, click the button „Calibra-tion“ and the submenu „PSO method“ to start basICColor calibrate. Highlight one or more measurements and confirm with <OK> to start the data calculation.

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The calculated values are shown in the form of a diagram and a table immediately. Please see which measurement is used for the calculation in the measurement name line. By clicking the „Average“ checkbox all imported measurement data is averaged and the measurement name line states: „Averaged values“The table shows the average value of each color from the measured values of a target that are shown in the diagram on the left side.

averaged CMYK measurement values.

reference values for CMY

reference values for black

measurement values outside the tolerance

density of the dry measurement

Lab -values with the corresponding reference

∆E dependant on paper type

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The first column shows the linear percentage values. Then you can see the measured values for CMYK. The right two columns show the FOGRA-set dot gain for CMY and K, de-pending on the selected paper type .

In the first three columns of the lower table you can see the Lab values of each color at 100 % . The numbers in brackets ( ) are the reference values for the selected paper type. The fourth column shows the ∆E of the measured values to the reference values. In the last column the density values are given at 100%. Keep in mind that these are dry measure-ment values measured with a device without polarizing filter . They therefore differ a little to the values that you have measured on the press during printing. Below the chart you can choose which channels should be displayed in the diagramm. In addition you can activate the corresponding reference . Thus you can quickly get an overview of the color behavior of your printing machine .

Figure 1 Figure 2 Figure 3 Figure 4

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The example shows a near perfect TVI in cyan (Figure 1). For magenta (Figure 2) the TVI is rising steadily from 40 %. In yellow (Figure 3) you can already see a deviation from the reference at 10%. This increases to more than 5 % deviation at 70 %. By contrast, black (Figure 4) shows significantly lower TVI between 5 % and 50 %. From about 55 %, the black curve is almost perfect to the reference curve .By this very unequal behavior of the printing units you should check if the inks are of the same type and age. Another cause for this behaviour could be uneven worn blankets.In the table below you can see the deviation of the Lab values at 100 % compared to the reference FOGRA39L. You can see in cyan, that due to the optimal TVI and the correct final density a good ∆E of < 1 is achieved . Responsible for this is also the correct ab value.

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In contrast, magenta with a ∆E of 5,18 is already outside the tolerance. Despite the correct final density a better result cannot be expected since the b - value with ∆b 5,1 is too blue and thus differs significantly to the requirements. Yel-low on the other hand, with a ∆E of 2,19, is still well within in the tolerance. The ∆E 4,02 in black is primarily explained by the low final density and thus the higher L-value. Here a little more ink could provide a remedy.

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2.5 Creating a TVI CorrectionThe software calculates an averaged value from the measured data sets and creates the correction data. If you switch to „Correction values“ in the pulldown menu below the data tables, the correction curves for the individual color channels are shown in the diagram. By clicking the indivi-dual color control checkboxes below the diagram you can view the each curve seperately.

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As previously mentioned, there‘s two ways of using the ba-sICColor calibrate calculated correction in the RIP. Either use the correction values of basICColor calibrate or the measu-ring data for the TVI correction in your RIP . Depending on which way you choose, you can export the correction data now.

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First select the data format for the RIP. If the RIP of the imagesetter already has a certain printing characteristic (eg FOGRA 39L ), export the measurement data using the button „Export characteristic print curve...“. If the by basIC-Color calibrate created correction (dependant on a selected paper type) should be used, the data must be saved via the button „Export correction curve...“

In each case select a unique name and folder in the follow-ing dialog box under which you want to save the file . The data format corresponds to the format for the previ-ously selected RIP.

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2.6 Example for Harlequin ReportTo be able to load the correction data into your image-setter RIP, the linearization file first of all must be copied to the folder ‘SW->caldata ...’: Please take care that the name of the file is ‘Import’. Then, select the respective PageSetup from the software of your imagesetter. If the basIC-Color calibrate calibration target was printed without plate correction, you should use the settings ‘Calibration and Tone Curves’ to ‘None ..’ from Calibration & Tone response. Otherwise, the correction curve of the imagesetter will be selected which was used to exposethe plates for the target.

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If the complete dot gain correction was undertaken with calibrate, you must setup a new ‘Calibration target’ using the ‘Calibration Manager’.

From ‘Device...’ choose Printing Press and from ‘Color Space...’ CMYK. Subsequently, click ‘New ...’.

From the upper popup menue of the following dialogue ‘Press...’ select the setting ‘Linear ...’. Afterwards click the button ‘Import ...’ to load the formerly copied Import file into the Calilbration Manager.

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The selection box ‘Channel ...’ may be used to display the corrections of the corresponding colour channels. Use the field ‘Name ...’ to save the name of this calibration and quit Calibration Manager. Afterwards use ‘Intended Press ...’in Page Setup to load the saved calibration. If the target was generated with an already existing characteristic print curve (e.g. FOGRA39L), a new calibration target will be generated as described above. In this case as import file not the correction data will be imported but the pure measu-ring data (actual values).This calibration target must be loaded in Page Setup using ‘actual Press ...’.

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Dot gain calculated with basICColor calibrate

Dot gain correction with FOGRA 39L asnominal value with characteristic print curve(actual value) calculated with basICColor calibrate

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2.7 Updating of Correction DataThis function is only used if the complete dot gain was corrected with basICColor calibrate, i.e. not an existing cha-racteristic print curve (e.g. FOGRA39L) was used. It does not matter if the imagesetter was calibrated separately.First of all the target with the gradients must be reprinted using the dot gain correction generated with basICColor calibrate. Once dry, remeasure the target.The procedure is exactly as described earlier when creating the calibration.The measured data is once again displayed in the diagram to view the quality of the calibration. If the original calibra-tion shall be improved, click the button ‘Update correction curve ...’ upon processing the measuring data. This will open a file selection to load the original correction which was used to print the new targets. A new import file will be calculated with the new measuring data and the already created correction. Use the following file dialogue to save this new correction. This import file can be loaded to the imagesetter RIP as described above. It will replace the origi-nal correction.

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To get an overview of the behaviour of the printing machi-ne it makes sense to save the measured data using ‘Save measuring data ...’. Select an easily identifiable folder name with date in the dialogue to be able to remeasure anddisplay the data using ‘Load measuring data ..’ at any time.

Chapter 3

Product InformationbasICColor calibrate

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3. Product Information basICColor calibrate

Copyright Information

Sofware - Copyright © 2007-2016 basICColor GmbH.All rights reserved.

Manual - Copyright © 2016 basICColor GmbH.

The contents of this manual are for informational use only. It is subject to change without any notice. basICColor GmbH takes no responsibility or liability for inaccuracies or erros that may appear in this document. No part of this manual may be reproduced, transmitted, transcribed or translated into any language without the written permission of basICCo-lor GmbH.

Trademark Information

basICColor and the Fingerprint are a registered trademark of basICColor GmbH. All other trademarks or registered trademarks are the property of their respective holders (Apple, Adobe, X-Rite, Konica Minolta Sensing, ColorPartner, Barbieri) Any mention of these trademarks is for demona-trational use only and is not meant to infringe any rights of a third party.

Written and compiled by: Werner Le RoyVersion 5.0, Januar 2016

Documents

Manual - basICColor GmbH · This manual only covers the basic operation of the ... precise calibration of CtP platesetters and presses ... Please refer to the basICColor catch manual