File preparation and transfer


  • If you are preparing a publication in Adobe InDesign, we recommend that you perform a preliminary layout check using the Preflight tool before submitting the PDF files. This saves your and our time and preventing possible layout errors. Short instructions on how to do this are available here.
  • The file should be supplied in PDF format. The file can be uploaded to BALTO Prepress portal Login details are given by the project manager.
  • Only files in PDF version PDF/X-4 are acceptable.
  • Each component of the book should be supplied in a separate PDF file: inlay, end/front sheets, cover, UV varnishing, foil, dust jacket, etc.
  • All the inlay pages should be supplied in one chain (composite). If the file is bigger than 2 GB, it should be split in two or more parts. In this case, file name should include page numbers (Inlay 001-150pp.pdf, Inlay 151-300pp.pdf).
  • Inlay file should be prepared page by page, not in spreads.
  • Cover and dust-jacket files should be prepared in spreads including the spine.
  • Blank pages should be included into the print-ready file.
  • The size of all pages must match the size of printed book.
  • If the book is printed in two or more different languages with changes in black color, constant and change parts of layout must be supplied in a separate files: constant CMYK in one file and changing K parts in a separate files.
  • If there is more than 10 pages with corrections, new full file must be supplied (not only new pages).
  • Files must not contain non-printable objects. Such as annotations or objects with an non-printing attribute assigned.


  • Required resolution of images is 300-350 dpi. Minimum required resolution is 250 dpi. The images in lower resolution may not look quality in print. Lower than 150 dpi images are not suitable for printing.
  • It is recommended to use 600-1200 dpi resolution for bitmap images.
  • Black texts and barcodes should be prepared in one color (not in CMYK). No color profile should be attached to such text. Black text in CMYK is a common mistake.
  • All the fonts used in layout should be embedded to PDF file.
  • Thinner than 0.2 pt lines (hairline) can not be used in the layout.
  • Tables, lines, text and other black elements should be prepared in only black color (K).
  • All the elements must be in CMYK color mode. RGB color mode is not suitable for printing.


  • All the elements must be converted to CMYK and Grayscale color modes or/and Pantone, HKS colors. There must be no elements in RGB, LAB, Multi Channel color mode. These color modes are not suitable for offset printing.
  • The layout for digital printing must contain only CMYK colors.
  • Overprints can’t be applied to white color. If overprint is applied to Pantone or HKS color, project manager must be informed about this.
  • It is recommended to apply overprint to 100% black color (K).
  • Gradients cant be lighter than 3% for one CMYK channel. Lighter gradient won’t be visible after the printing.
  • Please note, that hue of paper has an impact on colors. This is especially common for yellowish papers (eg. Munken).
  • Digital color proofs are always printed on semi matte coated paper or uncoated paper. This must be estimated when comparing the print to a color proof.


  • Trim Box and Bleed Box marks must be added to each PDF page.
  • Every page must contain 3-5 mm bleeds. Hardcover file must contain 18 mm bleed.
  • Trim Box size must match final size of the page.
  • Trim Box must be the same size for all the pages. If there is a reason why Trim Box size differs between the pages, project manager must be informed about it.
  • Text, page numbers, and other important elements should be no closer than 5 mm to cutting line (Trim Box).
  • For soft cover books, it is necessary to leave 7 mm width strips next to the spine of the first and last inlay pages. Also, 7 mm strips must be left on second and third cover. These strips will be glued, so no text or important graphic elements should be placed there.
  • For hard cover books, it is necessary to leave 5 mm width strips next to the spine of the first and last inlay pages. Also, 5 mm strips must be left on the last page of front-sheet and first page of end-sheet. These strips will be glued, so no text or important graphic elements should be placed there.


  • Spot UV, silkscreen, foil stamping, embossing and die cutting forms must be supplied in a separate vector file in PDF.
  • Offset partial varnish must be presented as additional Pantone color (overprint is required) in the same file (eg CMYK + Pantone).
  • The page size must match the final printed page format.
  • The file must contain Trim Box.
  • Objects to foil, emboss or varnish must be prepared in 100% K.
  • Objects to foil, emboss or varnish must match the printing layout.
  • Estimating the mismatch in the production process it is not recommended to overlap embossing or foil stamp with printed elements. Possible mismatch is up to 2 mm. Instead of overlap embossing with printed elements, it is recommended to choose embossing with foil.


  • In order not to exceed ink amount in the printing, the correct ICC paper profile must be used. Different paper profiles must be used for coated, uncoated and yellowish paper.
  • Total ink for coated paper should not exceed 330 %.
  • Total ink for uncoated paper should not exceed 300 %.
  • According to paper manufacturer, total ink for Munken papers should not exceed 260 %.


  • After the print-ready file is supplied, our repro specialist make a pre-flight checking. The designer is informed about the mistakes found. The designer correct the mistakes and supply new pages. If there is more than 10 pages with corrections, the full file must be supplied (not only new pages).
  • For the final approval digital print example is prepared (soft-proof). The soft proof shows the book  in a digital form. The soft-proof must be reviewed carefully and approved by mail before starting printing.
  • Resolution is soft proof is reduced to 250 dpi in order to compress the file. On a client’s request, the soft proof can be prepared in higher resolution.
  • Please note, that two soft proofs and are prepared for free. Third and every next checking and soft proof preparation is charged 50 Euros.
  • The client can refuse the soft proof by informing project manager by mail. The book will be printed from the file sent.
  • Production date depends on soft proof approval date. Production is scheduled only when the final approval is received. Standard product production term is 2-3 weeks starting the file approval day. Pre-flight checking should be accomplished within 24 hours.
  • Please use the newest version of Adobe Acrobat Reader for soft proof review. Overprint display option must be used (Edit → Preferences → General. Page Display → Use Overprint Display). This option lets to notice possible overprint and trapping mistakes. Mobile devices and device which does not support Adobe are not suitable for review of soft proof. Recommended Adobe Acrobat Reader program let you see images, bleeds, text and other objects in the same way as they look printed.
  • BALTO print does not take any responsibility for supplied print-ready layout and soft proof content; entirety of text and graphic elements; colorfulness; pagination; resolution; text and graphic elements critical position with Trim Box; insufficient contrast; spot UV, foiling, embossing position in accordance with layout.

You can get more tips about file preparation on YouTube channel „BALTO print class“.


  • All media submitted by the clients are stored until the product is completed and delivered to the client.
  • We do not undertake any responsibility for the media which were not reclaimed by the customers in time.
  • The received files are not archived and we undertake no responsibility for their further preservation.
  • Please contact our Prepress Department for any questions: [email protected].

Uploading files

All files for print are to be uploaded to

Please request your login information: