Newsletter #24 Behind the scenes of the DTP Studio

The most common mistakes in print file preparation and how to avoid them?

In our previous article, we explained why the document “Technical specification for print preparation” is such an important part of cooperation. It is not a set of limitations, but a practical guide that helps avoid mistakes, speeds up project execution, and ensures the best possible final result in offset printing. 

A properly prepared file means fewer corrections, greater production safety and confidence that the final product will look exactly as intended in the design. And because even the smallest detail can affect the final outcome, it is worth understanding which mistakes occur most frequently.

Bitmap resolution and print Quality 

Graphics downloaded from the internet often look good on screen, but after printing they may appear blurry or pixelated. This happens because printed materials require an appropriate resolution. The optimal bitmap resolution is 300 dpi (minimum acceptable: 260 dpi) at a 1:1 scale. Excessively high resolutions are also not recommended in offset printing. The better the quality of the source file, the better the final effect on the packaging or leaflet. 

Color profiles and the difference between RGB and CMYK 

Colors displayed on a monitor may differ from those achieved in print due to different color spaces. Screens work in RGB, while offset printing uses CMYK. If the design is not properly prepared for offset printing, colors and tonal transitions may appear differently after printing than expected. That is why using the correct color modes and profiles already at the design stage is so important. Our printing process is calibrated according to ISO 12647-2 standards (Fogra 39 / ISO Coated v2). 

Visual inspection and the CMYK reference standard 

Every project should be checked not only technically but also visually. Slight contrast differences, overly dark gradients, or poorly visible elements may become problematic after printing. In offset printing, the CMYK proof should always be treated as the point of reference — not the image displayed on a computer screen. 

Missing fonts in files 

One of the most common issues involves missing or improperly embedded fonts. In such cases, fonts may be automatically replaced with different typefaces, leading to layout changes, text shifts, or composition errors. To avoid this, it is recommended to convert text into outlines or correctly embed fonts in PDF files. 

Lines and small elements that are too thin

When designing for print, it is important to maintain minimum line thicknesses — both in positive and negative forms. Lines and elements that are too thin may become invisible or unreadable after printing, especially with finishing techniques such as hot stamping or embossing. 

Font size matters 

Small text may look fine on screen but become difficult to read on the final product. This is especially important for pharmaceutical leaflets and packaging containing large amounts of information. Maintaining appropriate font sizes affects not only aesthetics, but above all readability and user safety. 

Safe margins and crease lines 

Graphic elements and text placed too close to die-cut lines (cuts, creases, etc.) or cutting machine knives may become damaged or unreadable during production. Maintaining proper safety margins helps avoid such situations and provides greater control over the final result. 

Hidden layers and unnecessary elements in files 

Production files should contain only elements intended for final execution. Hidden layers, non-printing objects, or accidentally left comments may lead to misunderstandings or production errors. The more organized the file, the smoother and safer the production process. 

Why can a PDF file look different? 

It is important to remember that web browsers and various PDF viewers may display files differently. What you see on screen does not always reflect the actual production data. That is why professional file verification before printing is so important. 

For this purpose, we provide our Clients with the Customer Panel and its integrated Proofscope module – a platform that streamlines project collaboration and minimizes the risk of errors. It allows users to conveniently upload files, verify their content, and review mock-ups without additional software. 

The most important rule? Always carefully check the mock-up sent for approval by opening it in the Proofscope module. This is the most critical stage of graphic material verification before production begins. 

We will print exactly what you see in our Customer Panel.