standardisation in offset printing
What is PSO Certification?
Process standard offset printing – for plannable and reliable production
The offset printing process standard (PSO) describes a standardised procedure for generating print products. From the prepress stage through to the finished product. It allows the quality of the production process to be guaranteed from the capture of the print data to the end product.
What are the benefits of PSO certification?
All production stages are controlled, checked and monitored using suitable testing equipment and monitoring methods, which are prescribed by the PSO.
These include measuring equipment with densitometric and spectral photometric properties, as well as suitable testing elements such as a print control strip or media wedge.
The offset printing process standard (in accordance with ISO 12647-2) also specifies practical targets and tolerances for print production in the form of colour locations, colour distances, dot gains and dot gain spreads which must be complied with in order to pass certification to ISO 12647-2.
CONSISTENT HIGH QUALITY
Who certifies the process standard in offset printing?
IPM supports graphic companies in the introduction and implementation of standardised and industrial production processes along the entire process chain from proof to print.
The Living PSO/PSD! Konzept developed by IPM combines training, consulting, certification and award-winning software into a needs-based and practice-oriented concept for preventing errors, reducing costs, increasing productivity and quality assurance.
Process standard offset printing
What are the test criteria??
The advantages of certification to the offset printing process standard
can be grouped into three categories:
Category 1: Pre-press stage
In the pre-press stage, a distinction is made between data handling with colour management and the proof printing parameter
TC 1.1 Data handling
With data handling, you must be able to demonstrate that you are able to take supplied files, check them, correct them and prepare them ready for printing. The creation of printable PDF data is also expected.
TC 1.2 Colour management
With colour management, you show that you are able to control the handling of ICC colour profiles, have understood the principles of colour management and are able to implement them successfully. A profiled monitor and suitable framework conditions are also assumed.
TC 1.3 Proofing
You are able to demonstrate that you can generate a colour-accurate print simulation of all five paper types and are able to confirm the fidelity of their colour using measuring technology
Category 2: CtP and printing
This category is divided into printing plate production / imaging (CtP) and the setup of printing orders with the associated order continuous printing run.
TC 2.1 Printing plate production / imaging
You are able to image printing forms using the relevant checking materials and to inspect these either visually or using suitable measuring equipment.
TC 2.2 Continuous printing according to ISO 12647-2
In continuous printing with an order of at least 3,000 sheets in sheetfed offset or 6,000 roll-overs in web offset, you are able to demonstrate that the print run takes place within the permitted fluctuation tolerances set out in ISO 12647-2 (offset printing process standard).
If the test is passed successfully, you receive the measuring record as a written report and also as a PDF file. You also get the LIVING PSO!® seal of certification. You are able to use this on your company letterheads, for example, or as an advertising logo on your own website.
You will also receive a certificate valid for 12 months. All of the parameters tested are listed on the certificate.
Request comprehensive information on certification in offset printing (PSO) now!
How is the PSO certification process
The certification according to ProcessStandard Offset consists of 7 steps
Computer-to-plate check as well as linear imaging of the process parameter test printing form.
First, the measuring equipment used on your premises is checked, calibrated if necessary and aligned. Then comes the linear imaging of the test printing form, i.e. without any compensation or graduation curve.
This is then evaluated using measuring technology.
First proof with the IPM process parameter test printing form on two printing stocks.
Based on the IPM process parameter test printing form, we then determine all of the spectral photometric and densitometric parameters in the printing process for each printing condition (taking account the specifications defined in ISO 12647-2:2013). These include, for example:
- Inking series / CIELab full-tone densities
- Ink fade (dampening distributor use)
- Standardisation of target densities
- Trapping characteristics
- Inking: density spread
- Secondary colour locations (100% RGB) / tertiary colour locations (100% CMY)
- Slurring/ghosting check
- Dot gains and dot gain spread
- Characterisation of the individual printing units
- Printing contrast
- Screening: Moiré, dot bridging, radial and linear tonal value curve
Evaluation (1) of the measuring results and documentation of the print results.
PrintProcessControl assists us when analysing the measuring results and preparing them nominally as well as visually for process adaptation.
Using our optionally available process analysis tool, the checking, monitoring and documentation of all production parameters is virtually “child’s play”
Correction of the RIP LUTs for both printing stock and imaging of the printing plates.
The process schedules and imaging curves are created according to the printing process analysis for each printing condition. In this context, the
“make” of the RIP does not matter. You can simply rely on our expertise, which spans all manufacturers.
We will of course integrate the pre-press staff into the processes and, if required, train them specifically on the RIP so that they will be able to create characteristics or carry out corrections to imaging curves themselves!
Printing plates are then output with the IPM visual test printing form using the new imaging curves. The check using measuring technology is intended to verify the use of the new imaging curves.
Second print proof with visual test printing form for verification of the changes from step 4.
The second print proof takes place using the IPM visual test printing form. This includes both measuring technology and visual inspection elements. The informative images allow the screening quality and the print process quality for all kinds of motif types (skin tones, detail, structure, high/low colour assignment, lights, depths, metal, etc.) to be assessed and an initial visual comparison made between the print and a print proof or reference print (if available!).
Evaluation (2) of the measuring results, detailed adjustment of the RIP – LUTs, further CtP imaging.
For the visual assessment, the ECI GreyWedge is used with its grey balance fields and /or a customer proof or reference print.
Deviations and/or correspondences between the measuring technology and the visual impression are discussed.
The measuring technology-based assessment is compared with the corresponding imaging curves, taking account of the visual assessment. The resulting RIP corrections are then executed again.
Final print proof, final discussion, detailed IPM documentation.
he IPM visual test printing form captures all of the parameters relevant to the printing process using measuring technology and compares them with the specifications of the offset printing process standard as per ISO 12647.
The “final proof” with the IPM ECI visual test printing form allows characterisation data to be produced and the optional generation of ICC profiles in order to, for example, reliably integrate specific printing conditions (FM, hybrid) into pre-press processes (data conversion, image editing, proof section).
What do I receive following PSO certification?
You benefit: visible quality. For example, through customers who only place orders with certified printers and thus expect a more consistent and higher print quality.