How to prepare a file for large-format printing. Checklist before placing an order

How to prepare a file for large-format printing. Checklist before placing an order

The file has been uploaded. The order has been placed. And then you wait — not for production confirmation, but for feedback from the DTP department. Has the file passed technical verification?

In large-format printing, a technical file error is not something you can simply "fix in 10 minutes". It may mean stopped production, delayed delivery and a project with a hard deadline.

The checklist below will help you go through the most important file parameters before you click "order". Each point is based on Labo Print's official file preparation specification — no guesswork, just specific values.

Why large-format printing is different from standard printing — and why it matters for your file

In offset printing, 300 dpi is the standard. In large-format printing, paradoxically, you often need much less. A banner viewed from a distance of 3 metres requires a much lower resolution than a leaflet read from 30 cm away. Sending a 300 dpi file for a 3×1 m banner is not "better quality" — it is a file weighing dozens of gigabytes that the system will probably reject as too large.

The second key aspect is scale. A small technical error that may be invisible in A4 printing — for example, slightly insufficient bleed — becomes a white stripe along the entire edge on a 6-metre graphic wall.

The third issue is material. The same file printed on frontlit banner, sublimation fabric and self-adhesive film will produce three different shades of the same colour — which is why the colour profile and CMYK composition matter.

Checklist — 9 things to check before sending your file

Each point below is a requirement from the official Labo Print file preparation specification. Save it, print it or add it to your internal order template.

The most common errors in large-format printing files

The Labo Print DTP department sees these errors regularly. Some of them stop production. Others may require additional verification or file preparation again — and that always means time. It is better not to end up on this list.

• Overprints
  A function that prints one colour over another instead of knocking out the colour underneath. If it is not an intentional design effect — remove it. White overprint causes elements to disappear from the print.
• Open or double cutting lines
  Open paths prevent correct cutting. A double cutting line often appears after saving the file when the die-cut outline is not centred.
• Preview elements in the production file
  Thumbnails, watermarks and preview elements may remain in the file after export. Make sure the preview layer is turned off or removed before saving the production file.
• Unembedded graphics / links
  The file looks correct on your computer because the local links are available there. On the production side, the system sees empty spaces where the linked graphics should be.
• Missing bleed or bleed below 5 mm
  One of the most common mistakes in files prepared using online tools. The required bleed is 0.5 cm. Incorrect fix: do not change the file size — move the artwork instead.
• Rotated POS elements
  In POS materials, elements designed vertically sometimes end up placed horizontally in the file. The result in print: the display stands upside down.
• Files over 500 MB
  The file size limit applies. Prepare TIFF files with LZW compression, flattened to background.

What the DTP department checks before production starts — and when the file will be returned to you

In shop.laboprint.eu, the file undergoes technical verification by the DTP department before production starts. We check the basic parameters required for production, such as:

• file format
• compliance with the product specification
• bleed preparation
• presence of a preview file
• correctness of the most important technical settings.

DTP verification helps detect errors that could stop production, but it does not replace proper file preparation by the ordering party.

The customer is responsible for supplying a file that complies with the specification and is correct in terms of content, layout, graphics, colours and markings. If the file contains an error that prevents production, the order may be put on hold until a corrected file is delivered. If, however, an error present in the source file is not detected during DTP verification, any complaint resulting from that error remains the responsibility of the customer.

The checklist above is the shortest way to make sure your file passes verification the first time.

When the file requires changes — and what happens then

If the file contains an error that requires changes to dimensions, finishing or essential composition elements, the order will be put on hold and the DTP department will contact the customer.

This is a good moment to check the full Labo Print specification available directly in the shop, or to consult the project before placing the order.

If the project is inherently non-standard — a format outside the catalogue, an unusual substrate or a combination of several technologies — before placing the order in the shop, describe it to our sales department.

Non-standard printing project — what to do when the standard offer is not enough?

FAQ

What resolution is required for large-format printing?

It depends on the format: up to A0 — 150 ppi, up to 2 m — 100 ppi, over 2 m — 72 ppi. This is not a mistake. The lower resolution results from a greater viewing distance. Files prepared at 1:10 scale must have their resolution increased tenfold.

Does Labo Print accept RGB files?

Yes, but RGB files are automatically converted to CMYK based on the ISO Coated v2 profile. The printing house is not responsible for colour differences resulting from the conversion. We recommend preparing the file in CMYK from the start, with the correct black values for the selected printing technology.

Can the file contain an embedded colour profile?

No. Print files must not contain embedded colour profiles. If your graphic design software attaches a profile by default, disable this option when exporting to PDF or TIFF.

What is a preview file and is it required?

A preview file (PREV.jpg) is a screen-resolution preview attached to each order. The file name must end with the _PREV suffix. The preview file is required — without it, a complaint will not be accepted by the printing house.

How large can the print file be?

The limit is 500 MB. To stay within this limit for large formats, save TIFF files after flattening all layers, using LZW compression. Alternatively, prepare the file at 1:10 scale with the resolution increased accordingly.

What does the DTP department check and is the printing house responsible for file errors?

The DTP department technically verifies the file before production starts. The responsibility for preparing the file correctly and in accordance with the specification lies with the ordering party. The printing house is not responsible for print errors resulting from a file that does not comply with the specification. If the file requires corrections, the order is put on hold until a corrected file is delivered.