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- Gamut and Colour Profiles
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- PDF/X-4 and Other PDF/X Standards
- Process Standard Offset Printing
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- Proof of EAN / GTIN Codes for Large Retailers like ALDI and HOFER.
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Sphere Head Spectrophotometers and Specular Component Explained
Different surfaces can influence both the colour and the appearance of objects. A colourful and glossy object will usually appear more saturated to the eye, while a similar object with a matte, diffuse surface will appear duller.
If you form a glossy, a semi-matte and a matte surface from the same black plastic, the glossy surface will often appear blackest, while the very matte surface will appear much lighter. The same effect can be reproduced with film lamination of prints: a glossy laminated dark blue or black appears more saturated and darker, a matt laminated black becomes lighter and greyer to the human eye due to diffuse light refraction.
Humans perceive the colour of objects through the light reflected from them, and different surfaces reflect light differently. In general, therefore, there are two ways in which light is reflected from an object: The specular and the diffuse reflection.
Specular reflection
Specular reflection occurs when light is reflected from the light source at an equal but opposite angle. Simply put, you can think of it as a ball bouncing off a smooth floor and bouncing back at the same angle. This reflection occurs mainly on objects with shiny, smooth surfaces.
Diffuse reflection
If, on the other hand, the reflected light is scattered in numerous different directions, we speak of diffuse reflection. This reflection occurs on objects with matt and irregular surfaces. A ball would bounce off such a surface – for example, an irregular floor consisting of numerous pyramids of different sizes – sometimes at one angle and sometimes at a completely different angle.
Spectrophotometers with an integrating sphere
Today, when colour and gloss are to be evaluated in global supply chains and on different surfaces, this is often done with sphere head spectrophotometers such as the KonicaMinolta CM-26d, with which we at Proof GmbH have also measured the semi-matt and matt free-colour CIELAB HLC Colour Alas XL. With the d:8° geometry and the integrated 60° gloss sensor, which can handle both the SCI – “Specular Component Included” and SCE – “Specular Component Excluded” measuring modes, this measuring device can measure colour and gloss within less than a second without having to use an additional measuring device for gloss and always having to be set up and aligned again.
With integrating sphere measuring instruments, the surfaces to be measured are usually illuminated at all angles and measured at an angle of 8 degrees from the vertical axis. This measurement condition is referred to as d/8 or d:8. Most of the integrating sphere measuring devices such as the CM-26d can measure with or without a gloss component as previously described.
In contrast, the 45/0 models used in the printing industry such as the X-Rite i1 Pro2 always measure without the specular reflection. The reflection of the sample surface is therefore perceived differently by the optical geometries d:8 with gloss component – SCI – , d:8 without gloss component – SCE – and 45/0 respectively.
SCI measurement mode
To measure the true colour of an object without the influence of surface texture, the Specular Component Included (SCI) measurement mode is used. SCI mode includes both specular and diffuse reflected light and is ideal for quality control and colour quality monitoring.
- Illuminates the sample evenly from all sides.
- Takes into account the total surface reflection.
- Has good repeatability and is insensitive to surface variations or artefacts.
- Does not perceive gloss differences of the sample and therefore does not simulate visual assessment.
SCE measurement mode
The Specular Component Excluded (SCE) measurement mode, on the other hand, which excludes specularly reflected light, is used to evaluate the colour of an object to match the visual perception of the human eye. In SCE mode, a glossy surface is typically measured darker than a matte surface of the same colour; similar to how the human eye sees it. This mode is typically used in quality control testing to ensure that colour matches colour standards through visual inspection.
- Illuminates the sample evenly from all sides, but not in the reflection angle of the measurement.
- Excludes specular surface reflection, although usually not completely
- Includes diffuse surface reflection.
- Is somewhat sensitive to surface variability and unevenness.
- Measures the colour of a surface similar to how the human eye sees it.
Proof.de Parcel Labels: Now Paper Instead of Plastic
We have found a more environmentally friendly parcel sticker for our brown shipping boxes: Instead of a classic PVC sticker, we can now save the environment a little plastic with a paper label produced in offset printing, without compromising on quality and appearance. Admittedly, perhaps not a big step. But every small contribution helps to save our environment a little bit.
We have always used electricity from 100% hydroelectric power, print invoices and letters using energy-saving inkjet printing and have switched our IT to increasingly energy-saving computers, servers and NAS devices.
In addition, for the past two years we have been participating in the German Packaging Act through our partner Veolia, with the aim of minimising the impact of packaging waste on the environment in Germany.
Our annual disposal contribution serves to implement Directive 94/62/EC on packaging and packaging waste. The aim is to further increase recycling rates in Germany.
Proof.de / Proof GmbH is a Member of Fogra
Proof GmbH is a member of Fogra – Forschungsinstitut für Medientechnologien e.V.. Why? In recent years, we have been able to draw on the support of Fogra with numerous projects, or work together with Fogra, for example for Fogra58 beta – Textile-RGB (where Matthias Betz was also able to report on our experiences as a speaker at the Fogra Colour Management Symposium 2020 in Munich as part of the presentation “Proofing of Fogra58beta”) or have contributed test prints and proofs to the research project “11.004L – Improving the printability and readability of bar and 2D codes in inkjet printing”.
In addition, we have been certified by Fogra every year since 2013 for the production of proofs (https://shop.proof.de/en/info/fogracertification.html) and are very grateful for the services of Fogra, which confirm the quality of our proofs every year, also externally.
Our most important contact person, Dr. Andreas Kraushaar, has often promoted membership to us, and now we have actually taken the step, although we still think that the membership fee is poorly structured, especially for small companies like Proof GmbH (companies with 1-100 employees pay the same membership fee) and we would like to see a more favourable entry. But on the other hand it is true: Fogra with its expertise, its competence and its always competent, helpful, quick and fit contact persons like Andi Kraushaar, Yuan Li and many more also deserves the support of companies that benefit from Fogra’s activities like we do.
We would therefore like to thank Fogra for all the support we have received and knowledge we have gained over the years. From now on, we are a member of Fogra and look forward to many more discussions, projects, ideas and initiatives.
New at Proof.de: The EPSON SureColor SC-P9500 Spectro
For whatever reason: December is traditionally the month in which we make the most important new acquisitions. In order not to break with this tradition, the new proof printer generation from EPSON moved in with us this year: The SureColor SC-P9500 Spectroproofer.
Unpacking traditionally has to be done in front of the door, we wouldn’t be able to get the printer into the office on the two-metre-long pallet, but once it’s on rollers, it works fine.
The new SureColor P9500 complements our range of SureColor 7000 and 9000 proof printers and, above all, hopefully brings us a further plus in speed, especially for larger jobs. Thanks to a newly developed and now fully loaded print head with 12 inks with up to 800 nozzles each, it is said to print up to 2.4 times faster than our other proof printers, which is particularly advantageous for large proof volumes.
An overview of the most important new features of the EPSON SureColor 9500
- High productivity thanks to higher production speed
- Reliability thanks to better automatic jet inspection and dust protection
- LCD display with 4.3 inch (10.9 cm) touch panel
- Simultaneous use of glossy black and matte black, eliminating the need to switch inks
- Lighting at the paper feed for better visibility of the printing process
- Prints now fall on the reverse side in the delivery, which should reduce scratches
- Higher print resolution with 1200×2400 DPI
- “Black Enhancement Overcoating” technology for higher perceptible black density
We are currently still in the process of measuring the large number of media we use on the new printer and gaining experience with the new proof printer. Many of the “advantages” are not really relevant for us, as we have very specific requirements in proof printing. In terms of gamut, i.e. the maximum colour space that can be achieved, we were unfortunately unable to determine any real gain. According to our measurements, the colour space has changed marginally compared to the previous proof printers, but not really increased.
2.4 times the printing speed does not automatically mean that the proof printing will also be faster … 🙂
For example: Admittedly, the printer prints much faster than our other printers. But in return, it takes much longer to transport the proof paper to the fans for drying, and the subsequent measurement of the media wedge also takes longer than on the 7000 and 9000 systems. For an A4 proof with media wedge and test report, the 9500 is only 8 seconds faster, taking just over 8 minutes. In other words, the higher print speed is almost completely lost in other areas.
Therefore, A4 proofs will not be the domain of this printer, but rather we will try to proof the larger formats on the 9500, where the speed advantage comes into play more.
This reminds me a little of the upgrade to Fiery 7, which was supposed to be up to 5 times faster than the previous version with FastRIP technology. In fact, the FastRIP technology was and is so error-prone that we were never able to use it, as we felt that every 20th job was processed incorrectly or could not be processed at all. On the other hand, with the version upgrade, the entire proofing software became considerably slower … So for us as non-FastRIP users, all that was left on average was a slower system.
Conclusion:
And so we are still making our experiences with the new proof printer. The first conclusion we can draw is that many things are better, some are worse and some are simply different. The fact that the printer is still quite new is also evident from the fact that new media updates are constantly being added. We have already run some good jobs through the printer and it has not disappointed us. In this respect, the first conclusion looks fairly optimistic.
Proof GmbH 2020 Once Again Fogra and Fogra “Spot Cert” Certified
This year we have again submitted proofs for Fogra certification. We thus prove that we not only deliver excellent proof quality through internal quality controls and checks, but that the quality of our proofs is also confirmed by an external body. We have therefore had proof prints certified for the seventh year in a row. Already in 2019, we have also been certified for the representation of spot colours ("Spot-cert"), and in 2020 we were the first company ever to add the Fogra-59 certification:
- We were certified for the new Fogra 59 eciCMYK-V2 standard for the first time
- We have again carried out a certification for PANTONE spot colours for all four printing conditions, the "Spot cert". We certified the spot colours PANTONE 2270 C, PANTONE 151 C and PANTONE Cool Gray 6 C for the proof standards ISOCoatedV2, PSOCoatedV3 and eciCMYK-V2 and PANTONE 2270 U, PANTONE 151 U and PANTONE Cool Gray 6 U for the standard PSOUncoatedV3.
The quality of our prints and our spot colour reproduction of PANTONE colours has been confirmed to us by Fogra for all four proof standards.
You can download the complete 14-page test report from Fogra here.
We have implemented the new certifications on the current software revision Fiery XF 7.1.3 and on the papers EFI Gravure Proof Paper 4245 Semimatt, EFI Proof Paper 8245OBA Semimatt and EFI Proof Paper 8175OBA Matt. 
Publication of Fogra 56/57 for Glossy and Matte Film Lamination of PSOCoatedV3 Prints
A few days ago Fogra published the characterisation data for the new printing standards Fogra56 and Fogra57 while ECI provided the respective ICC profiles for download on the eci.org website.
FOGRA56 and FOGRA57 are the separation and printing standards for matte and glossy film lamination of "PSO Coated v3" / Fogra51 prints.
Fogra56 / PSO Coated V3 Matte Laminate
The ECI offset profile PSO_Coated_v3_Matte_laminate.icc is based on the characterisation file "FOGRA56.txt" and applies to the following printing conditions according to the international standard ISO12647-2:2013:- Commercial offset, premium coated paper, dot gain curve 2013-A, followed by matte film lamination (typical OPP matte film 15 μm with medium opacity ~70%, i.e. lightening ΔL* = 6 on black solid after finishing), white measuring base.
- The profile is consistent with the PSOcoated_v3.icc profile and shows the matching glossy finished result.
- The profile was calculated using Heidelberg ColorToolbox 2019 with the following settings: Black length 9 (insertion point 10%), Black width 10, max. area coverage 300%, max. black 96%.
Fogra57 / PSO Coated V3 Glossy Laminate
The ECI offset profile PSO_Coated_v3_Glossy_laminate.icc is based on the characterisation file "FOGRA57.txt" and applies to the following printing conditions according to the international standard ISO12647-2:2013:- Commercial offset, premium coated paper, dot gain curve 2013-A, followed by glossy film lamination (typical OPP glossy film 12-15 μm), white measuring pad.
- The profile is consistent with the PSOcoated_v3.icc profile and shows the matching gloss finished result.
- The profile calculation was done with Heidelberg ColorToolbox 2019 with the following settings: Black length 9 (insertion point 10%) , Black width 10, max. area coverage 300%, max. black 96%.
PANTONE Combines Metallics and Premium Metallics Fans
Printed graphics PANTONE Metallics (previously referred to as "Metallics")
Metallic inks for non-packaging projects Marketing and sales materials, publishing and literature. The colours are based on the seven classic PANTONE Gold and Silver Shades 871 to 877 C.Packaging PANTONE Metallics (previously referred to as "Premium Metallics")
Metallic packaging inks for packaging printing. These former "Premium Metallics" colours are created with the basic colours Pantone Silver 10077 and Pantone Rose Gold 10412. These special inks are made with pigments that are easier to process with water-based and UV varnishes. The varnish seals the inks, this protects the inks and thus provides the protection that is often required in the packaging sector. According to PANTONE, the new inks offer- Better print results
- Greater brilliance
- Higher gloss
- More durability
- Less leafing and tarnishing in the long term
PANTONE and EFI? No chance.
After having implemented the new PANTONE colours in our proofing system over the past few days via a difficult update from Fiery XF, we noticed that the new Metallics colours were still missing. Currently, the PANTONE Metallics colours for packaging printing are not yet supported by Fiery XF, and there are no plans to support them, according to Fiery Support. For us an incomprehensible decision. Admittedly, metallic colours cannot be reproduced in the proof anyway, as only the colour but not the metallic gloss can be reproduced. For us as a service provider, however, this decision by EFI means that we - when customers order proofs with Premium Metallics colours - have to create them manually with LAB values in the job, because our proofing software will not recognise all current PANTONE colours, but will mark them as unknown special colours and refuse the proof. Since the current PANTONE V4 colour palettes can only be integrated into the Adobe product palettes with considerable effort on the part of the users, it is not quite clear to me whether the lack of colours in Fiery is due to a profit-driven, ostentatious PANTONE licensing policy or a miserly, ostentatious EFI product policy. However, be sure: We at proof.de will provide the service and also offer these colours for the proof. We owe this to our customers.Barcode Check: New in ISO 15416:2016
The "ISO/IEC 15416:2016 - Information technology - Automatic identification and data capture methods - Test specifications for bar code print quality - Linear symbols" specifies the current criteria for testing bar codes. ISO 15416:2016 replaces ISO 15416:2000 and defines modified bar code quality calculations for some areas. During the barcode check by Proof GmbH, barcodes are checked according to the current criteria of ISO 15416:2016.
An overview of the most important changes in ISO 15416:2016:
Four of the seven barcode parameters - symbol contrast, modulation, defects and decodability - were previously graded by whole numbers, so the evaluation could be 0, 1, 2, 3 or 4. With the adoption of the ISO/IEC 15416:2016 standard, evaluations are now graded to one decimal place. So under the old standard there were only five possible parameter gradations (0/1/2/3/4), now there are forty-one (0.0/0.1/0.2 etc. to 4.0).- This also changes the rating with letters. Since this is even less precise than the evaluation by numbers, it is omitted in the new standard, whereby the usual letter notes can still be provided for information purposes. However, the nominative standard must be given as a decimal number.
- Defects are now calculated methodically differently. A defect is a light spot on a dark bar or a dark spot on a light surface. If a defect was at the edge of a bar or a gap, the old standard gave a worse rating than the same defect that was further from the edge. The calculations in the new ISO/IEC 15416:2016 standard describe the effects on the readability of the barcode much more accurately.
eciCMYK_v2 / Fogra 59 Available for Proof
The new CMYK exchange colour space eciCMYK v2 (FOGRA59) is the successor of eciCMYK (FOGRA53) from 2017. The new "V2" profile is based on the revised characterisation file FOGRA59. For the same colour space, the new profile offers a significantly modified and improved grey axis, which now contains the familiar cyan, magenta and yellow components from classic printing processes. Thus eciCMYK v2 offers a further advantage besides a large colour space and proofability. Practical tests with various digital printing systems have shown that, in addition to the conversion from "ISO Coated v2" to "PSO Coated v3" data, the assignment of the new CMYK exchange colour space profile also enables improved output on digital printing systems with a larger colour space: the printed image appears richer in contrast, with brighter colours. The icc-profile "eciCMYK_v2.icc" can be downloaded from the ECI in the download section. Proofs in the eciCMYK_v2 colour space can now be ordered in the shop at Proof.de.
Device Link PDF Colour Conversions for Ads
We have recently started offering DeviceLink colour conversions via DeviceLinks made by ColorLogic from numerous RGB and CMYK standards into other CMYK standards from offset and gravure printing.
Optimised colour conversion between different printing standards
The colour conversion profiles preserve the separation structure, limit the total colour application for the selected printing standard and maintain the purity of the primary and secondary colours. They ensure smooth transitions in gradients and enable correct conversion of PDF and PDF/X data. Separation-preserving conversion ensures that pure grey tones are not built up into four colours and that duplex tones (black+primary colour) and triplex tones (black+secondary colour) remain pure, while still being colour-metrically transformed in the best possible way. In addition, the colour impression of the source colour space is optimally preserved in the target colour space by taking into account both paper colouration and dot gain.Limitation of Total Allocation of Colour (TAC)
For current printing standards of ISO, Fogra, ECI, Ifra, Gravure (PSR), Gracol, Swop, SNAP, these profiles ensure a targeted limitation of the maximum ink application without completely new separation. This reliably prevents problems with set-off and improves the drying behaviour. These profiles are suitable if the data is generally already in the desired colour space, but individual images or objects have too much ink application. You can order the Devicelink PDF colour conversions for advertisements here(more…)
Proof.de Support Chat Software updated
Today we updated our chat software Livezilla Pro to offer you even more comfort and speed in the chat. Simply contact us directly via chat ... a lot of minor details or brief queries can be dealt with quickly and conveniently. In addition to security updates and performance improvements, the chats should now be even more reliable in every possible browser and PC combination. Uploading and downloading files such as screenshots in the chat history should also be improved. A word about data protection: We don't use any supposedly free chat solutions based in Las Vegas, we care about the protection of your data and your anonymity in the chat:
- We use the chat software of LiveZilla GmbH from the beautiful town of Singen in Baden-Württemberg,
- anonymise or mask automatically the last 6 digits of your IP address,
- host the chat software on our own server and
- have of course SSL-encoded the chat with you.
- All data is transmitted purely via our server,
- there is no access by third parties and
- Livezilla works without cookies.
What is a finishing proof? Fogra49 and Fogra50 in detail.
With the proof standards Fogra49 and Fogra50 for the first time a proof standard was created that is not binding for printing. Why? Fogra49 and Fogra50 describe two colour spaces as they are created by foil lamination not after printing but after printing and finishing.
- Fogra 49 refers to the ICC profile: PSO Coated v2 300% Matte laminate (ECI) - PSO_Coated_v2_300_Matte_laminate_eci.icc
- Fogra 50 refers to the ICC profile: PSO Coated v2 300% Glossy laminate (ECI) - PSO_Coated_v2_300_Glossy_laminate_eci.icc
Why were these profiles created?
Print finishing plays an increasingly important role in the further processing of printed matter. The application of a printing varnish, for example, is nowadays usually done directly during the printing process, e.g. with dispersion varnish in a 5th inking unit. The print image is usually only slightly changed in the process: An dispersion varnish, for example, results in a dot gain of 2-3 percent, a UV varnish up to around 5-7 percent. In contrast, foil lamination with OPP foil has a much stronger (more…)Pantone Plus vs. Pantone: Farben, Fächer und Probleme.
Im Jahr 2010 stand eine der zentralen Neuerungen im Hause Pantone für Grafiker, Dienstleister und Druckereien an: Die Pantone Palette wurde um zahlreiche Farben erweitert und bekam einen neuen Namen: Pantone Plus Die Erweiterung um 560 Farben erfolgte in zwei Schritten:
2010: Plus 224 auf insgesamt 1341 Pantone Solid Farben
Im Jahr 2010 wurde die Pantone Palette um 224 Farben erweitert, die in der Pantone Nomenglatur die Farbnamen von 7548 bis 7771 tragen. Alle neuen Farben konnten weiter in der Druckerei mit bisherigen 14 Pantone Basisfarben angemischt werden.- PANTONE Yellow
- PANTONE Yellow 012
- PANTONE Orange 021
- PANTONE Warm Red
- PANTONE Red 032
- PANTONE Rubine Red
- PANTONE Rhodamine Red
- PANTONE Purple
- PANTONE Violet
- PANTONE Blue 072
- PANTONE Reflex Blue
- PANTONE Process Blue
- PANTONE Green
- PANTONE Black
2012: Plus weitere 336 auf insgesamt 1677 Pantone Solid Farben
Im Jahr 2012 wurde die Pantone Plus Palette um weitere 336 Farben erweitert, die in der Pantone Nomenglatur die Farbnamen von 2001 bis 2336 tragen. Damit diese Farben erzielt werden können, wurden die bisherigen 14 Pantone Basisfarben um 4 neue Farben auf insgesamt 18 Basisfarben erweitert. Die neuen, aus der Pantone GOE Palette entlehnten Farben sind:- PANTONE Bright Red
- PANTONE Pink
- PANTONE Medium Purple
- PANTONE Dark Blue
PDF X/4 data – who calculates? InDesign or the RIP?
Recently we received a PDF file from a Swiss customer who asked us to proof it according to ISOCoatedV2. The format was PDFX-4, we could open the file, preflight it and also display it in Acrobat. However, when proofing in Fiery XF 5.2, the file was only output after a RIP time of over 3 hours. Adobe PDF X4 screen output in Acrobat Professional We have recorded the screen layout on a modern Macbook Pro with four processor cores and the latest Acrobat Pro version to illustrate the enormous demands on computing power. It was clear from the screen layout that the RIP time would be quite long, but three hours with just one use was quite unusual, especially since in our RIP two instances of the Adobe PDF Print Engine work simultaneously. Where exactly the error lies in the extremely high RIP time is not yet clear. Both EFI, as the manufacturer of the Fiery RIPS, and Adobe, as the manufacturer of the PDF Print Engine (APPE), have been given the information that on a Harlequin RIP the file was probably ripped within a few minutes. So a bug in the Adobe PDF Print Engine might also be a reason for the long processing time. It' s a typical problem. From creation programs such as InDesign and Illustrator, the flattening of file elements with X/4 is passed on to the RIP in the print shop or proof printer. The case in question was calculated on a quad-core system with SSDs with two instances of the Adobe PDF Print Engine and output correctly for three hours 47 minutes. However, since the final product cover is not expected to be produced in Europe, but in Asia, it was decided to break down the complex graphics with transparencies, drop shadows, etc. in Photoshop and then reuse it as a transparent PSD file. The resulting PDF X/3 file was ripped and proofed within seconds. The colour result was identical to the X4 file. This example shows: PDF X4 is not just a modified data format. It also shifts the computing power and software requirements from the data creator to the data processor or printing house. But especially with complex graphics this can lead to unpredictable effects. Although PDF X/4-capable solutions such as Fiery XF 5.2 do exist today, a RIP time of over three hours is of course not practical.
Proof.de Introduced new measuring technology: X-Rite SpectroProofer ILS30
With the new SpectroProofer ILS30 made by X-Rite, Proof GmbH has created the basis for automated measurements and Proof verifications according to M1 standard. Proofs with optical brighteners (OBAs - Optical Brightning Agents) can now be measured. Contrary to earlier announcements, the new SpectroProofer are also able to measure the current proofing standards as before in M0 measurement standard.
Because of the new ILS30 SpectroProofer, the layout of the Ugra / Fogra media wedge was slightly modified. For a comparison between old and new media wedge, see the image below.
Proofing with individual ICC profiles
We received a call from a new customer today: He proofs for Chinese suppliers, and up to now he is producing proofs in Japan Color 2001 Coated (JapanColor2001Coated.icc). We had not yet set up the profile in our RIP, but within a short time we were able to load the profile into our RIP, create workflows, and make the profile available for order in the shop.
We will gladly integrate your individual ICC proof profiles and create proofs for you.
We proof more than 50 international proof standards, but there are always one or two standards that we do not yet offer. Often ink manufacturers or paper producers also offer ICC profiles like Aniva or Heaven42 and the Munken, Amber and Arctic paper series from Arctic Paper. Or have you measured a house standard for your printing parameters which you would like to use for proofs? Then please contact us. We will be happy to support you.Why is the embedding of RGB profiles so important?
A few days ago we received a call from a customer in the field of design, who sent open Adobe InDesign data in ISOCoatedV2 300% with contained RGB images to the production company for a complex CD production on the advice of the producing company ("The printing company still has a prepress stage, which can then prepare your data optimally..."). The result of the finished printed CD booklets and inlays did not correspond at all to the calibrated monitor image of our customer, the client was also unhappy and requested the print data about the production company from the print shop responsible for the print to troubleshoot. Data in the "US Web Coated" color space with 350% ink coverage came back from the printer. For troubleshooting, the customer then had a proof of his data created by us, but had chosen the settings "Convert to target profile (retain values)" as usual when writing the proof PDF; we thus received completely CMYK data, of which we produced a proof according to ISOCoatedV2 300%, which completely met our customer's expectations. So it seems that the designer created the data correctly and printed the print shop incorrectly. On closer inspection, our error analysis revealed two serious weaknesses:
- On the one hand, the obviously wrong profile conversion of the print shop with InDesign CS2 to "US Web Coated", a completely outdated profile never used in Europe, which was delivered with early Creative Suite versions and was probably never adapted due to a lack of competence on the part of the print shop.
- On the other hand, the open InDesign file of our customer, which he had sent to the production company, contained RGB images without a profile (DeviceRGB), which cannot be safely interpreted.
How do we deal with RGB data at Proof.de?
If we receive a PDF file that contains RGB images, the next step is to check if the file is a valid PDF/X-3 or PDF/X-4. If this is the case, we check whether all input RGB profiles are correctly marked with color space (sRGB / AdobeRGB / ECI-RGB-V2 etc.) and rendering intent, then we check whether the correct output color space was used as output intent and whether also contained CMYK data have the correct input profiles. If yes, then we proof the file with the settings: "Consider all input and output color spaces". In this case, the file is reproduced 100% exactly as our customer created and defined the color profiles. If he has made a mistake and e.g. marked an image with a wrong RGB profile, this will also be "incorrectly proofed" exactly as correctly. If RGB data should not contain a profile, e.g. if they are created in Device RGB, we generate a "data incorrect" e-mail in which we explain our procedure as follows: "Dear customer, the data check has shown that RGB elements are contained in your data. RGB elements can only be safely interpreted in the proof if they are marked with a color profile and a rendering intent. This is the case, for example, with correct PDF/X-3 and PDF/X-4 data. The correct output intent must also be specified. At least one of these criteria does not seem to be the case for your file. The safest way would be to convert the contained RGB data to CMYK. This has the advantage that you have control over the conversion and can view the CMYK result again in Acrobat before uploading the file again for proofing. We can then reliably use your CMYK values for the proof. To do this, call up the current order in your customer account, delete the incorrect data and upload the corrected data. If, for example, the RGB element should only be a small image that is not relevant for the overall impression of the proof, or if you do not have another file available for the proof, then of course we can also use your RGB data for the proof. If available, we use your RGB source profiles and rendering intents, otherwise we use the sRGB standard and the rendering intent "relatively colorimetric with depth compensation", which in most cases will lead to correct proof results. If you would like us to proof the supplied RGB data in this way, please let us know. Please do not hesitate to contact us if you have any questions. Best regards, your proofing team". In our case, the CD production case would also not have occurred in the proof, as we reject RGB data not provided with an ICC profile with the error message mentioned above, and do not convert them, as we cannot predict precisely how our customer would have liked the data to be converted. We are aware that our approach is not 100% the ultimate best approach in all cases, but to the best of our knowledge and belief it is best in line with market practice and the expectations of our customers. However, we are also happy to accept your individual requirements and circumstances. Give us a call or send us an email and describe your processing requirements.Colour Management Consulting and Expertise
DIN SPEC 16699 “Open colour communication” published
A few days ago, our DIN SPEC 16699 "Open Colour Communication" was published and is now available for free download from DIN's Beuth-Verlag.
Matthias Betz from Proof GmbH, Holger Everding from DTP Studio Oldenburg, Jan-Peter Homann from Homann Colormanagement in Berlin and Eric. A Soder from Pixsource in Switzerland, all members of the association freieFarbe e.V., have shown in the bilingual DIN specification a way to create high-precision color samples on the basis of open source, license-free standards and have shown ways for cross-media color communication.
The 44-page PDF is bilingual in German and English and can be ordered directly from Beuth Verlag, which distributes the DIN standards in Germany, and downloaded free of charge after a short registration.
Proofs for recycled paper. Is that possible?
We produce proofs for classic white uncoated papers on a daily basis, but the question often arises as to which proof standard could be used for printing on recycled paper.
In general, the paper white in a proof is precisely defined in the proof standard and is also measured in every test report.
For PSOUncoated it is 95.00 / 0.00 / -2.00 in CIELAB and for PSOUncoatedV3 it is 93.50 / 2.50 / -10.00, i.e. slightly darker (93.50 instead of 95.00 for brightness L) and significantly bluer (-10.00 instead of -2.00 on the B axis, i.e. the blue-yellow axis in the blue direction).
Recycling papers differ not only greatly from type to type in the area of paper white, but even from batch to batch. So if a printing company orders the same recycling paper in January and in February, the paper mill may well deliver a slightly different white value of the paper, as the paper white of course depends strongly on the recycled paper qualities used for production.
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Recycling papers
White-point sample 1 -
Recycling papers
White-point sample 2 -
Recycling papers
White-point sample 2
A colour-binding proof for recycling paper is therefore not possible, as no standard has ever been worked out due to the different paper qualities and white tones.
It is recommended for the proof to choose a classic proof standard such as PSOUncoated / Fogra 47, which shows a rather neutral, unbrightened paper white in the proof. Place one side of the recycled paper next to the proof and mentally transfer the colour of the proof to the white tone of your recycled paper. This way you can imagine the later printing result quite well.
Paper white of many paper manufacturers and online printers measured
We spectrally measured the paper white tone and the proportion of optical brighteners of over 1,000 papers of the most important paper manufacturers such as Berberich and Papier Union as well as online printing companies such as Flyeralarm and wir-machen-druck.de.
Only a few paper manufacturers currently publish data on paper whiteness and the proportion of optical brighteners in their papers, but only technical indicators such as whiteness according to ISO 2470-2 or CIE ISO 11475. However, designers can hardly record paper whiteness with these values. In addition, it is not possible to read from these data whether and what proportion of optical brighteners the paper has.
Example above: Spectral data comparison of Antalis Coqueror CX 22 white for the measurement standards M0 and M1. Below you can also see the color deviation in Delta-E00 of 1.97 and the two paper white values in LAB and LCH.
Left: CGATS.17 Data for measurement conditions M1 and M0 for paper Antalis Conqueror CX 22 white
We have therefore measured the most important papers and dyes of all central paper producers and paper distributors as well as online printers in the three measurement standards M0, M1 and M2. From the difference in the paper whiteness of the two measurements M2 (UV cut without UV portion) and M1 (ISO 3664:2009 with noticeable UV portion), we determined the color distance on the yellow-blue axis of LAB in Delta-b and derived from this the proportion of optical brighteners according to Delta-B according to ISO 15397 and evaluated it.
Delta-B conversion: OBA share in the paper
Delta-B < 1 = faint OBA
Delta-B < 4 = little OBA
Delta-B < 8 = low OBA
Delta-B < 14 = moderate OBA
Delta-B > 14 = high OBA
Spectral data of all measured papers for download
Parallel to the images of the spectra, we have also provided spectral data in CGATS format for the measurement modes M0, M1 and M2, which can be downloaded for any paper. These values can be used, for example, in proofing software to calculate a paper white simulation for a specific production paper.
You can easily order proofs from our shop:
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Proof GmbH
Gölzstraße 17
72072 Tübingen
Baden-Württemberg
Germany
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