Approximately 80% of the artwork files sent by customers present issues that need to be fixed manually or are simply unusable (Print Industries Alliance). And the three main reasons for this happening are quite predictable: lack of bleeds, low image resolution, and RGB files. This is not fine print that nobody reads. These are common mistakes that can be easily prevented if you know how to do it.
When the deadline doesn’t move
File errors are expensive not only because you have to reprint but also they consume time. And what you don’t have when you’re in a production crunch is that – time. For instance, when a brand needs to rush order stickers for a show or a new product launch, a single file rejection due to missing bleed, wrong color mode, or unembedded fonts, can set the whole job back by 24 hours or more as corrections are made, and new files are sent in. If it’s a 24-hour job to start with, boom, you’re late.
If all these technical prepress details are taken care of before the order is even finalized, the print-ready file (with bleed, a correctly named dieline layer, outlined fonts, CMYK color, and 300 DPI imagery) goes to press immediately. No hold-ups, no back and forth emails, no missed deadline.
Color mode: why RGB files print wrong
The colors you see on your computer screen are created by light. Your screen pours red, green, and blue light into your eyes in varying combinations to generate the full spectrum of visible color, and some colors that simply do not exist in reflective ink. CMYK printing does the exact opposite, stacking layers of cyan, magenta, yellow, and black ink on a surface to subtract light from hitting your retina.
So when you take an RGB document to a printer, their prepress software performs the conversion. It’s this automatic conversion step that causes everything to go haywire. Neon green, electric blue, and many oranges fall completely outside the CMYK color gamut, so the software simply selects the nearest available CMYK ink, which is often a much less vibrant hue than the one you selected on screen.
Correcting this problem is simple. Slam down the CMYK preview in your design software at the start. You’ll instantly see which of your precious, lurid colors falls outside the printable color book, which ones go genuinely fluorescent, and which ones simply turn muddy and disappointing. Adjust the ones that matter while you’re still in control of the project. That’s you, right now. Neons often need to be reined slightly darker or warmer. This step is much less painful than doing it later when it’s a surprise.
And if you can’t live with that, you need to get to grips with spot colors. For brand-critical colors – a logo that has to match across business cards, stickers, and packaging – CMYK process printing introduces variability. Spot colors (Pantone/PMS) are pre-mixed inks that deliver a specific, reproducible hue regardless of press conditions. If color consistency across print runs is non-negotiable for your client, specify Pantone values and confirm the printer supports them. Not every commercial printer runs spot color jobs, but knowing whether yours does will save a conversation after the fact.
Resolution: why you can’t fix a low-res image in settings
The print industry standard for raster images is 300 DPI, or dots per inch, at the final output size. Web images are 72 DPI. Monitors are low pixel density, so a 72 DPI image displays fine in the browser. Printing a 72 DPI image gives a visibly pixelated result.
Sadly, here’s what a lot of people don’t realize: you’ll never turn that 72 DPI image into a press-ready 300 DPI image by adjusting the resolution setting in Photoshop. Without resampling the image, all that change does is spread the existing pixels over a smaller area in the software. The basic number of pixels never changes. No fresh data gets added.
When software does introduce pixels to get a 300 DPI image from an insufficient-resolution source (upsampling), it does so by estimating values based on the tones of surrounding pixels. The new pixels introduced in this process make the image appear soft and out of focus, because you’re not adding detail, just estimated values. This passes the resolution check but doesn’t print well at all.
If you’re handed a client’s low-res 72 DPI JPEG logo to run in a two-color stationery suite, go back and beg for the native vector file or a proper export from the client’s design program. It’s a lot less painful than having to share in the cost of the reprint and explaining the problem.
Bleed, safe zone, and the mechanics of cutting
Physical cutting is imprecise. Even modern die-cutting equipment drifts slightly during a production run – a fraction of a millimeter in any direction. When that drift happens on a design that fills edge to edge, you get a thin white border on one side where the substrate shows through. It looks like a mistake because it is one, and it’s entirely preventable.
The bleed area solves this by extending your background color or image 0.125 inches beyond the trim edge on all sides. When the cut drifts slightly, it still lands within your printed area. The white border disappears because there’s no white to expose.
The safe zone works the opposite direction. Any text, logos, or critical design elements need to sit at least 0.125 inches inside the trim edge. Elements placed close to the edge risk being partially cut off if the die drifts the other way. The zone between the bleed edge and the safe zone boundary is where nothing important should live.
Set up both in your document from the start. Most design applications let you add bleed when you create the document – add it then, not as an afterthought.
Dielines for custom shapes
A dieline is simply a vector path that tells a machine where to cut. For square/rectangular business cards, or standard prints, the trim marks in your PDF take care of that. For unusual shapes – a logo-shaped sticker, or a product label with a notch in it – you’ll need to draw your own custom dieline.
The custom shape you draw should be a closed vector path, stroked at 1pt, on a layer all to itself, called “Dieline.” You should have filled this path with a spot color – usually something like bright magenta, or a pre-built swatch called “Dieline”; this hyper visible color lets the prepress software detect the path alone without messing with the rest of the file. Keep this layer hidden from your design layers, and double-check to ensure the spot color of the dieline won’t accidentally print as part of the design.
As far as actually building the shape goes, you can use the same software you’re designing the rest of your product in; Illustrator tends to be the standard choice here. Use the Pen tool to draw the path, or create it as an offset of your main artwork’s shape. (Heads-up: confirm with your printer whether they want the dieline in a layer within your main file or as a separate PDF, and they may want the layer style if it’s staying in the main file.)
Fonts: convert everything to outlines
Font substitution errors often cause prepress delays. When your file calls for a font, the prepress system makes a substitution of the closest match available if that font is not found, causing your carefully set headline to break over two lines.
To avoid this, simply convert all text to outlines (or “convert to curves” in some apps) before exporting final artwork. This is done in Illustrator by selecting all text and choosing Type > Create Outlines. In InDesign, you do this upon export by checking “Convert to Outlines” in the export settings.
Once text is outlined, it’s no longer text. It’s treated as a vector graphic and therefore no longer “reads” the font on the computer. This means you will get the expected result – every time. It will work the same on every computer. The only thing to keep in mind is that you should save an editable version of your file before outlining all text. This way you can still make text edits in the future if you need to.
Black: flat versus rich
Flat black corresponds to 100% of the Black (K) channel while the other channels are set to 0%. It is a solid dark color. Rich black is close to flat black but it also contains some percentage of the other print color channels in it.
This rich black is a combination of 60% Cyan (C), 40% Magenta (M), 40% Yellow (Y), and 100% Key (K) plate, which is the black plate. You can see it’s like the flat black but more “vivid”.
Flat black is used for small text because in the printing process each ink has a slightly different screen which means the registration can vary a little as to where the ink falls on the page causing the edges of small details to be blurry.
Rich black is used for larger fills because the other colors add to the total perceived density of the ink and the eye will pick up on the darkening. For tiny details like the letterform, it will not become as apparent.
Sticker-specific considerations
There are a few practical limits on sticker printing that don’t come into play with flat printed sheets. The most frequently encountered one: if your design runs fully to the die-cut edge with no margin, it can be difficult to get a fingernail under it and peel off the backing because the edge is not where the user expects it to be. Some designers leave a small unprinted notch, others deliberately add a kiss-cut backing slit.
Another laminate-related phenomenon rarely pointed out to designers is that since glossy laminate reflects light at acute angles, it can obscure very-fine detail. It’s also a fingerprint magnet. What’s a lot more visible is the compelling color depth and (obviously) gloss it adds to the sticker. For matte laminate, which may appear suboptimally dull/foggy at first, there’s a softer, slightly more “premium” feel, and it prints/”reads” more easily in direct light. Also, it’s easy to write on with a ballpoint pen.
Beyond aesthetics, if your sticker is going to be used in a high-traffic or high-moisture environment (e.g., stuck on a refrigerated bottle that will “sweat” whenever it’s taken outside), there are a number of different “substrate + laminate” combinations that should be tested for wet and rub performance.
File format and packaging
We strongly prefer PDF/X-1a or PDF/X-4 print-ready files because they are standardized ISO formats that embed color profiles, flatten transparency, and provide many of the details a prepress technician needs to print a job without problems. PDF/X-1a is the less sexy of the two; it does not allow live transparency or layers in a PDF, but it provides the best ICC color management and guarantees that your file will look the same when printed as it did on your screen. We generally recommend X-4 for more complex files, though; it allows live transparency, and it can be an easier format for less experienced users.
When you are ready to submit your PDF/X-1a or PDF/X-4 file, first gather the components you’ve been linking to. In Adobe InDesign or Illustrator, you can easily make a package that gathers the INDD or AI document, all the linked high-resolution raster images, and the ICC color profile (the last is in the document itself). This process guarantees that you won’t inadvertently have a linked image that’s gone missing, or linking to a low-res screen preview instead of the high-res original image.
Next, run the preflight check that’s part of the program you’ve been using (this is true for QuarkXpress, too). It will alert you to missing links, RGB images, un-outlined fonts, and missing bleeds. Just about all you’ve accomplished in your file can go to waste if you don’t make sure the preflight is clean and free of errors, so don’t just think “Oh, that’s just a warning.” Fix everything it flags.
A working checklist
Before you send in a commercial print file, go down this list:
- Is your document in CMYK, not RGB?
- Are all of your raster images 300 DPI at final output size?
- Did you extend the bleed 0.125 inches on all sides?
- Are all of your critical elements inside the 0.125 inch safe zone?
- Is your dieline on a dedicated spot color layer (if applicable)?
- Did you convert all of your text to outlines?
- Are your black fills correct – rich black for large areas, flat 100K for small text?
- Did you export your file as PDF/X-1a or PDF/X-4 with the color profile embedded?
- Did you run a preflight check with no errors remaining?
Most print problems aren’t mysterious. They come from the same short list of oversights, and every one of them has a mechanical explanation and a straightforward fix. Build these checks into your workflow from the first file you open, not the last step before submission.