Large format printing has its own set of artwork requirements. Customers coming from offset, small format, or screen printing often find that files prepared for those processes don't translate cleanly to wide format output. The result is delays, reprints, and disappointing colour.
The good news is that most of these issues come down to a small number of preventable mistakes at the artwork stage. Mediapoint has produced thousands of large format jobs for print resellers, signage companies, and agencies across Australia, and the same five problems account for the majority of delays we see.
Below are the five most common large format printing mistakes, and how to avoid them.
1) Supplying RGB Files Instead of CMYK
RGB is built for screens. CMYK is what comes out of a printer. The two colour spaces don't translate cleanly, and the difference between an on-screen RGB file and the printed CMYK output can be significant — particularly with deep blues, vibrant greens, and bright oranges.
Artwork should be set up in CMYK from the start, not converted at the end of the design process. Converting at export loses colour intensity, and the printed result rarely matches what was approved on screen.
For colour-critical work — brand colours, corporate identities, or repeat jobs that need to match between runs — specifying a Pantone C colour provides a more reliable reference. Inksets vary between printers and between machines, so Pantone C ensures that colour matching remains consistent regardless of where the job is produced.
2) Leaving Fonts As Live Text Instead Of Outlines
Fonts are a frequent cause of artwork issues. There are thousands of fonts in circulation, and there's no guarantee that a printer will have the specific font used in a file installed — particularly for bespoke fonts, recently purchased fonts, or fonts in non-English alphabets. When a font isn't available, graphic design software will substitute it automatically, and the substitution often isn't obvious until the proof is reviewed.
Converting all text to outlines before exporting the PDF eliminates this risk. Outlining converts text into vector shapes, locking the appearance in place so that the printer doesn't need access to the original font.
Most trade printers don't proof artwork before printing, which keeps turnaround times fast and pricing competitive. The trade-off is that supplied files need to be print-ready. Outlining fonts is the single most effective step a designer can take to ensure artwork prints as supplied. For more on what trade printers expect from supplied artwork, see how to evaluate a trade printer.
3) Using Raster Images Where Vectors Would Work
Vectors are the preferred image format for large format printing. They're built from mathematical formulas rather than pixels, which means they remain sharp at any size. Logos, text, icons, and shapes should be supplied as vectors wherever possible.
Raster images, by contrast, have a fixed pixel count. Scaling them beyond their native resolution causes pixelation, and there's no way to recover detail that wasn't there to begin with. In large format printing — where artwork may need to scale to several metres wide — this difference becomes critical.
Vectors carry a secondary benefit: they store CMYK values directly, which contributes to more accurate colour reproduction in the finished print. Sharper edges and better colour accuracy from the same file.
Raster images are still appropriate for photographs and lifestyle imagery — the rules on DPI below apply in those cases. The key is choosing the right format for the job rather than defaulting to rasters when a vector would do.
4) Forgetting To Flatten Gradients
Gradients are interpreted differently by different Raster Image Processors (RIPs). The RIP is the software that converts a print file into instructions for the printer, and not all RIPs handle live gradients the same way. A gradient that displays correctly on screen may band, shift colour, or render unevenly once it's been processed.
Flattening gradients before export removes this variability. The gradient is baked into the file, leaving nothing for the RIP to interpret. The process takes seconds in Illustrator or InDesign and removes a common cause of inconsistent output.
For designers who regularly supply files with gradients, flattening should be a standard step in the pre-export checklist.
5) Not Checking Artwork At 100% Before Sending
Viewing a PDF at 100% zoom before export is the simplest quality check available, and one of the most overlooked. At 100%, the artwork displays at the actual size it will print. Pixelation, low-resolution images, and other quality issues become obvious — issues that are invisible at 25% or 50%.
For files set up at a reduced scale (common for large banners), the zoom level should match. A file built at 10% of final size needs to be viewed at 1000% to assess print quality accurately.
The standard DPI target for large format raster images is 120 DPI at final print size. Higher resolutions produce diminishing returns: file sizes increase, RIP processing slows down, and the visible quality improvement is minimal. Lower resolutions risk visible pixelation.
A worked example: a 3-metre banner file built at 10% scale should be set up at 1200 DPI. When scaled to final size (3 metres), the image lands at the 120 DPI target.
It's worth remembering that large format prints are designed to be viewed from a distance. The ink dot size is larger than small format to handle outdoor durability, so artwork that looks coarse at arm's length will read correctly from a few metres back. The relevant test is how the print looks at the intended viewing distance, not how it looks up close.
Pre-Send Checklist
Before sending a large format file to print, run through the following:
- Artwork built in CMYK, with Pantone C references where colour is critical
- All text converted to outlines
- Logos and design elements supplied as vectors where possible
- Gradients flattened
- File checked at 100% scale on screen
- Raster images at 120 DPI at final size (adjusted up if the file is built at reduced scale)
These six checks cover the vast majority of artwork issues encountered in production. Substrate-specific or job-specific issues that remain will typically be identified and flagged by the trade printer before the job goes to press.
Frequently Asked Questions
What DPI should large format printing be?
120 DPI at final print size is the standard for large format raster images. Higher resolutions produce diminishing returns; lower resolutions risk visible pixelation.
Should artwork be in CMYK or RGB for large format printing?
Always CMYK. RGB is designed for screens, while CMYK matches the inks used in printing. Files should be set up in CMYK from the start rather than converted at export.
Do fonts need to be outlined in a print-ready PDF?
Yes. Outlining fonts converts them into vector shapes, removing the risk of font substitution. This is the single most effective step to avoid printing delays.
What's the difference between vector and raster for large format?
Vector images scale infinitely without losing quality because they're built from mathematical formulas. Raster images are pixel-based and pixelate when scaled beyond their native resolution. Vectors are best for logos, text, and shapes; rasters (at 120 DPI minimum) are appropriate for photographs.
Why do gradients sometimes print incorrectly?
Different RIP software interprets live gradients differently, which can cause banding or colour shifts. Flattening gradients before export eliminates this variability.
Getting Large Format Jobs Right The First Time
Addressing these five common mistakes eliminates the bulk of artwork issues that cause delays in large format printing. Each takes minutes to implement and pays back on every subsequent job.
For print resellers, agencies, and signage companies looking for a trade-only printing partner with fast turnaround and no minimums, contact Mediapoint to discuss your requirements.
