In case of complex artwork featuring special effects it is recommended that the files should be created by means of Adob
Specifications for preparing artwork for OFFSET PRINTING
CONTENTS 1. GENERAL COMMENTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. BASIC DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. PAGE LAYOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4. PDF FILES GENERATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 5. COLOUR SEPARATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 6. ICC PROFILES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 7. PROOFS CONTROL AND CERTIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 8. PROOFS VISUAL EVALUATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 9. ADDITIONAL COMMENTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 10. CTP STANDARD SETTINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 11. SUBMITTING ARTWORK FOR PRINTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 12. DEADLINES FOR SUBMITING ARTWORK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 13. DELIVERY ACCEPTANCE CRITERIA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
These specifications have been valid since October 5, 2010.
1. GENERAL COMMENTS This document defines the technical parameters and preparation manner of artwork intended for printing at Mellow Sp. z o.o. It has been drawn up with the intention to briefly outline to our customers the technical requirements of preparing artwork for cut-sheet offset printing. Complying with the guidelines set forth herein will for one thing help us satisfy your expectations with regard to customer service and product quality, and for another will allow us to meet the printing production standards.
2. BASIC DEFINITIONS Sample materials – materials that serve as a colour guide in the printing process. Sample material can be a printed sheet approved by the customer or a certified contract proof. Uncertified proofs or some previously done prints can also serve the same purpose but then the colour sample is for reference purposes only. Contract proof – a type of sample material that accurately imitates the ultimate printing effect of a given printing method. A proof becomes a contract proof after it has been duly certified. Proof certification – a process of controlling the accuracy of proof production which consists in determining the colour discrepancy between the values measured on the control strip featured in the proof and end values. The end values are determined with regard to the ICC profile used in the proof production. Proof certification takes place in the printing house. Certified proof – a proof that features the results of ΔE colour discrepancy measurement provided that the colour discrepancy does not exceed the standard set in the ISO norm 12647-2. ICC profile – a digital file that insures consistent colour. This file is specific to each device and contains information about how that device produces colour. ICC profiles are in compliance with the requirements set out in the ICC specification. Bleed – any graphic image or element that extends beyond the trim edge which defines the finished size of a printing page. Using bleeds is necessary to allow for deviations in cutting the paper to finished size because slight movement of the paper on the press or movement during cutting could result in items that are supposed to bleed off the edge not quite reaching the edge – leaving a bit of paper showing at the edges. Bleed allowance extends the image off the page a sufficient amount to counteract these slight deviations.
3. PAGE LAYOUT • • • • • • • • • • • • • • • •
In all artwork markers of the finished size must be indicated. All pages must be in the same orientation (horizontal or vertical). With materials intended for imposition densimetric scales should not be used. With multi-page publications all pages should be prepared in exactly the same manner i.e. have the same format, be centred and numbered (in a single file together with intentionally blank pages). Centrefolds should be treated as separate pages and submitted in separate files. Paste-ups are required with unconventional materials or materials without pagination. With artwork intended for die-cutting all the cutting lines should be marked with an additional colour, with the overprint fill option on. Black graphic elements and texts should be prepared with the overprint fill option on. Artwork will be printed in accordance with submitted files. Graphic resolution: 300dpi. If artwork contains any additional colours, such information must be given. With artwork intended for UV varnishing or embossing, a file featuring the varnish and embossing die layouts is required. All fonts and graphic elements should be positioned min. 5 mm of the trim edge. Also, it is recommended that a 10 mm distance of the trim edge should be kept for essential graphic elements (especially long ones that run parallel to the edge). All pages should allow for min. 3mm bleeds. Fonts should be included (embedded) in the PDF file or made into curves (not recommended). Min. font sizes for scripts printed in one colour are as follows: – for monoline scripts: 6pt – for scripts of variable width lines: 7pt. Min. font sizes for scripts printed in four colours or in reverse are as follows: – for monoline scripts: 8pt – for scripts of variable width lines: 10pt.
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Min. acceptable line width is 0.25pt. Lines printed in reverse or in more than one colour should have a width of at least 0.75pt. Black texts of more that 24pt can be printed with four colours according to the component content listed in para. 5. With artwork intended for perfect binding no graphic elements must be placed on the inside of the spine of the cover nor within 4mm of the spine in both directions (i.e. to the left and right of the spine). The effective format of centrefolds placed on the inside of a cover will diminish by the width of side gluing, i.e. by 3mm (applies to perfect binding). The effective format of centrefolds placed inside the publication will be smaller than their nominal format due to the fact that the publication cannot be fully opened (applies to perfect binding). An appropriate correction (image duplication at the inner edge of the page) should be allowed for in the file. Please note that Mellow makes no corrections to page layout or format. With artwork intended for saddle stitching it needs to be taken into account that the effective format of the publication inner pages will diminish as a result of the increase in the thickness of the spine – the so-called ‘push-out’ effect. At the customer’s request Mellow can correct the arrangement of pages at the imposition stage to compensate for the ‘push-out’ effect. The correction extent is estimated on the basis of the page count and the paper basis weight. This operation, however, involves image reduction along the spine (the nearer the centre of the book, the bigger the image reduction). In such cases it is automatically assumed that the page layout/design allows for this kind of operation. With brochures intended for saddle stitching the overall number of pages must be dividable by 4.
4. PDF FILES GENERATION • • • • • •
In case of artwork devoid of any special effects (shades, transparency, etc.) we accept direct export to PDF files from any graphic application. The files should be compatible with PDF version 1.4. The correct settings for files export from Adobe applications can be downloaded from www.mellow.com.pl. In case of complex artwork featuring special effects it is recommended that the files should be created by means of Adobe Acrobat Distiller version 5.0 and beyond. The correct settings for printing postscript files and their distillation in Acrobat Distiller can be downloaded from www.mellow.com.pl. The preferred postscript printer driver is ‘Adobe PDF’. The installation mode of *.jobsettings files in the system is explained in the attachment that comes together with the files. PDF files generated with the use of ‘jobsettings’ profiles available from www.mellow.com.pl ensure complete compatibility of the files with the CTP system employed at Mellow. Screen ruling, resolution and angles will be overwritten at Mellow.
5. COLOUR SEPARATION • • • • • •
The total ink limit (TIL) should not exceed: – 300% for coated paper – 270% for uncoated paper. In dubious cases the TIL value should be consulted with Mellow. Black background should not be obtained from black exclusively, but also the max. TIL value should not exceed 220%. In order to obtain a neutral tone of black the cyan content should be increased by about 10% in relation to magenta and yellow, e.g. C – 40%, M – 30%, Y – 30%, K – 100%.
6. ICC PROFILES All graphic elements must be rendered in CMYK. Artwork submitted in other colour spaces such as RGB or Lab will not be accepted. The conversion to CMYK colour model should be carried out using the widely available ICC profiles which are compliant with ISO 12647-2 and specific to particular types of paper: • ISOcoated_v2_300%_ECI.icc (for coated, glossy and matt paper) • PSO Uncoated_ECI.icc (for uncoated, offset paper)
The above-mentioned ICC profiles can be downloaded for free from www.mellow.com.pl
In case of printing on a special type of substrate that is not mentioned above, the kind of ICC profile used should be consulted with Mellow. In case of using paper that has unconventional parameters for its class (e.g. whiteness degree, finishing method) colour consistency might be limited.
7. PROOFS CONTROL AND CERTIFICATION • • • • • • • • • • • • • • • • • • • • • • • • •
It is recommended that each job submitted to Mellow should be accompanied by a contract proof (with multi-page jobs a contract proof for each individual page should be provided) All contract proofs submitted to Mellow must include the name of the job which they refer to along with the name of the ICC profile by means of which they were produced. All proofs should be certified. If the customer is unable to provide one then Mellow can produce the proof and carry out its certification at the customer’s expense. All proofs submitted to Mellow should feature a control strip that allows proof control and certification. Recommended control strip: Ugra/FOGRA MediaWedge V. 2.0a. Acceptable deviations from sample values are as follows: – ΔE for the background colour < 3.0 – ΔE mean < 3.0 – ΔE maximum for primary colours (CMYK) < 5.0 – ΔE maximum < 6.0 – ΔH maximum for primary colours (CMYK) < 2.5 – ΔH mean for grey balance < 1.5 Measurement requirements: – white background – illuminant D50 – observer 2° – no UV filter – no polarizing filter – measured absolute value with no regard for background colour Proofs should be produced using exactly the same files as those that will be submitted to Mellow, i.e. files where final corrections were made before going to press. Contract proofs should be produced by means of appropriate ICC profiles depending on the planned printing substrate: – ISOcoated_v2_300%_ECI.icc (for test prints on coated, glossy and matt paper) – PSO Uncoated_ECI.icc (for test prints on uncoated, offset paper). Using ICC profiles other than those recommended by Mellow needs to be consulted with the printing house. Proofs should include an imitation of a printing substrate. In the event when the customer has failed to provide a proof or the proof has not been produced in conformity with this specification Mellow can produce a contract proof at the customer’s expense. If the customer refuses his consent, the provided proof can be used as a sample by the printer but it has to be borne in mind that this may result in major colour discrepancy for which Mellow will not be held responsible.
8. PROOFS VISUAL EVALUATION Due to a phenomenon known as ‘metamerism’ the visual evaluation of proofs, and in particular their consistency with ready prints, should be carried out in standard lighting conditions conforming to ISO 3664:2000: – lighting with spectral distribution similar to illuminant D50 (corresponding colour temperature – 5000K) – the CRI indicator should not be lower than 95. Illuminance on the evaluated surface should amount to ca. 2000lx. The surroundings and backgrounds used for proof evaluation should appear neutrally grey and matt.
9. ADDITIONAL COMMENTS • • •
Owing to the imperfections of offset printing technology it needs to be taken into account that contract proofs might not reproduce 100% the colours eventually obtained on a printing sheet. In the event that the customer grants his print approval, the printing sheet approved and duly signed by the customer becomes a sample material. If submitted artwork contains any additional colours, such information must be given. The verification of Pantone colour
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reproduction is carried out through making spectrophotometric measurements and comparing the discrepancy (ΔE) between the obtained colours and Pantone colour guide. Previously done prints are not the same as contract proofs and they can be used by the printer for reference purposes only. Using this sort of sample materials involves the risk of obtaining inconsistent colour due to the lack of information concerning the artwork preparation manner and applied printing method. Also, colour inaccuracy might result from a different imposition method as well as discrepancies arising from paper colour and pigment changes over time. Prints subjected to subsequent UV varnishing or foil fusing are likely to change their colours in relation to those featured in the contract proofs. At Mellow we verify each time the accuracy of artwork submitted for printing. We cannot guarantee though that all errors and deviations from the guidelines set out herein will be noticed and accordingly dealt with. All additional activities aimed at bringing the submitted files into conformity with this specification i.e. all revisions, error corrections and alterations will be deemed new work and invoiced in addition to the printing fees.
10. CTP STANDARD SETTINGS We apply the following default settings: • screen resolution: 2400dpi • screen ruling: 175lpi • screen angles: C-15° M-75° Y-0° K-45° • AM screen, elliptical shape
11. SUBMITTING ARTWORK FOR PRINTING • •
Artwork should be submitted as composite PDF files. Interior and cover layouts should be submitted in separate files.
12. DEADLINES FOR SUBMITING ARTWORK • •
Artwork is considered to have been successfully submitted upon receiving artwork that is complete and needs no further corrections. Failure to meet the deadline for submitting digital artwork may result in potential delays in turnaround times for which the Mellow will not be held responsible.
13. DELIVERY ACCEPTANCE CRITERIA A delivered end product is considered to have been made in compliance with the submitted order specifications if 98% of the product stays within the quality parameters provided for herein.
www.mellow.com.pl
Mellow Sp. z o.o., ul. Zawila 61, 30-390 Krakow High-volume print & Direct mail: 30-390 Krakow, ul. Zawila 61 Tel.: +48 12 260 59 00, Fax: +48 12 269 19 21 Low-volume print: 31-526 Krakow, ul. Kielecka 2 Tel.: +48 12 421 93 89, + 48 12 218 08 08, Fax: +48 12 421 13 55
