Hi Juris 2010/2/24 Juris Valdmanis <bebris(a)jt.lv>lv>: Thats, true. Are those "high" densities tried using standard tone value increase (i.e. correct plate corrections)? Maybe some of those troublesome type 2 papers behave more like type 4 papers or maybe somewhere in between (i.e. not suitable for ISO 12647-2 production). It is dry colours. You need to establish wet density values for those dry Lab values. Martin Weberg

Papertype 2.... I call High quality Silk paper type 2 even if the B values are more like B-5. Only on these papers can we reach Fogra39 within low dE. We have made a custom "Papertype 2.5" category for all those matt papers wich will give higher dotgain and does not dry as fast as Silk does. We lower our Densities and reaches aprox 90% gamut volume of Fogra39 (close to dE5). This way we can also reach TVI A/B without problems. We put quite many paper qualities under our "Papertype 2.5" category and measure and calibrate on one of them. We also explain this to our customers, specially if they want contract proof. There will be some mismatch when comparing to Fogra39-certified proofs. Den 24. feb. 2010 kl. 14.10 skrev Juris Valdmanis:

Hello Juris, paper type 1 and paper type 2 as well as paper type 4 in the ISO standard are typical papers with defined values like paper white, gloss and mass per area. There are a lot of papers in the market that are not in the tolerances or ranges of the specified values. Most papers behave like the specified papers but there are also papers which are different. For example a paper type 1 with mass per area 90 g/m2 does not work like a paper with 115 g/m2 as mentioned in the standard. In such a case you have to define a new printing condition with new CIELAB values for the primaries and secondary's because it is not possible to put the same amount of ink on this paper. You have to carefully derive new density values for such a paper. The same is true for different coatings. It is not possible for an international standard to reflect or address all the different properties of papers of the same type in the market. The web-offset printers established different printing conditions for their different papers and so you have to do this for your papers if it will be necessary. Regards Guenter Bestmann Dr. Guenter Bestmann Research and Development Prinect Heidelberger Druckmaschinen AG Dr.-Hell-Straße D-24107 Kiel Germany E-Mail: guenter.bestmann@heidelberg.com<mailto:ernst.mustermann@heidelberg.com> Tel: +49-431-3863887 Fax: +49-431-3863287 Chairman of the Supervisory Board: Dr. Mark Wössner Board: Bernhard Schreier, Vorsitzender - Dirk Kaliebe - Marcel Kießling - Stephan Plenz Principal place of business: Heidelberg - Amtsgericht Mannheim - Registergericht - HRB 330004 - VAT.-IdNr. DE 143455661 From: eci-en-bounces(a)lists.callassoftware.com [mailto:eci-en-bounces@lists.callassoftware.com] On Behalf Of Juris Valdmanis Sent: Wednesday, February 24, 2010 2:10 PM To: eci-en(a)lists.callassoftware.com Subject: [ECI-EN] paper types and target LAB values Hello dear list members. First of all I would like to thank everyone who helped me last time I asked my questions! Your help was valuable! But now I have more questions regarding printing to ISO. In ISO documentation there are Lab target values for primary and secondary colors for different paper types. As we are sheet-fed printers we are interested only in paper type 1(gloss coated), type 2 (matt coated) and type 4 (uncoated white). As I understood from documentation (I have only an old english version of ISO 12647-2 and english is not my native language as you may already realized) all papers what we use for printing I have sorted in these three types of paper. But from documentation papers type 1 and type 2 have the same Lab target values for primary and secondary colors. >From my previous conclusion papers like fine gloss (with 3 coating layers) and rough matt (with only one coating layer) have same Lab target values. No problems with type 1 (gloss) papers, as we can get very close to target values and densities are ordinary. But for mate papers (type 2) we have to rise densities to get acceptable Lab values. It could be understandable as paper surface is rougher and you have to apply more color to get same saturate colors as on paper type 1. Problem is that higher densities however lead to different problems in postpress as paper is not drying well and it smears. Did I understood correct ISO documentation or am I missing something? And also I did not find answer to another question: Are Lab target values for wet or dry colors? Thank you, everyone. regards, bebris ________________________________ Confidentiality note: The information in this email and any attachment may contain confidential and proprietary information of Heidelberger Druckmaschinen AG and/or its affiliates and may be privileged or otherwise protected from disclosure. If you are not the intended recipient, you are hereby notified that any review, reliance or distribution by others or forwarding without express permission is strictly prohibited and may cause liability. In case you have received this message due to an error in transmission, we kindly ask you to notify the sender immediately and to delete this email and any attachment from your system.