If you’re ready to submit your artwork for printing at Peterborough Print, there’s one topic you absolutely should get your head around: colour modes. You’ve probably heard of CMYK and RGB—but what do these terms actually mean, and why do they matter so much for the look of your final prints? Let’s demystify it all and make sure your designs leap off the page, not fall flat.
What Are RGB and CMYK, Exactly?
RGB: The Digital Colour Mixer
RGB stands for Red, Green, Blue. This colour mode is what your computer monitor, phone, or TV uses to display images. Each pixel on your screen is created by mixing these three coloured lights at various intensities. When all three are at their brightest, you get white; turn them all off, and you get black. The more you mix, the lighter and brighter the colours become.
RGB offers a huge range of vibrant, “clashy” colours—think of those luminous neons or electric blues you see online. It’s perfect for anything viewed on a screen.
CMYK: The Printer’s Palette
CMYK stands for Cyan, Magenta, Yellow, and Key (Black). It’s the colour mode nearly all printers—ours included—use for physical printing. Unlike the light-based RGB system, CMYK works in inks or toners—combining these translucent inks subtracts light to create colours (hence why it’s sometimes called a subtractive process). When you mix all the colours, you get rich black; using none gives you white (or, really, the colour of the paper).
CMYK covers a more limited range of hues and can’t achieve quite the same super-bright tones as RGB. Still, it’s the industry standard for anything that’s going to be ink-on-paper.
Why the Difference? Because Your Eyes and Your Prints See Colours Differently
Here’s the catch: what you see on your screen isn’t always what comes out of the printer. Your device loves RGB because it can pump out nearly every colour your eye is capable of seeing, while CMYK is a bit more reserved (and realistic) in its range.
- Colour Gamut: RGB shows millions of hues, including extra-bright neon and deep, electric tones.
- CMYK’s range: Some RGB colours—especially striking greens, vivid reds, and deep blues—won’t print as you see them onscreen. They’ll shift or mute when switched to CMYK.
So, even if your design looks perfect on your laptop, you can end up surprised (and possibly disappointed) by how it turns out in print—unless you set your artwork up properly for print!
Why Is This Important When Submitting Artwork to Peterborough Print?
Like most professional printers, we print using the CMYK system. When artwork arrives in RGB, our software automatically converts it to CMYK before production—which can create unexpected, sometimes dramatic colour shifts. You’ll get much more predictable, accurate results if you convert your artwork to CMYK yourself, tweak as needed, and then submit.
It’s all about control: you want to make adjustments on your terms, not rely on a machine to do its best guess for you.
Common Colour Conversion Surprises
Here are some things people often notice when their bright-and-beautiful digital file goes to print:
- Neons vanish: Bold, luminous RGB colours (like bright turquoise or hot pink) will mute. They’re just not printable.
- Reds shift: Your fire engine red could end up more brownish or orangey.
- Blues & Purples fade: Deep, digital blues often take on a purple or grayish cast.
- Teals turn murky: That punchy teal shifts greener and less vibrant.
Tip: If colour is absolutely critical to your brand or design, always ask us for a printed proof before we run your final job.
How to Set Up Your Artwork for Flawless Colour
1. Start Your Design in CMYK
If your work is destined for print, start in CMYK from the get-go. Most design programs (like Adobe Illustrator, InDesign, or Photoshop) let you pick your colour mode at the start—choose CMYK for anything that’s going to paper!
- In Photoshop: File ? New ? Colour Mode ? CMYK.
- In Illustrator: File ? Document Colour Mode ? CMYK.
- In Canva: Download ? PDF Print, then pick CMYK in the advanced colour settings.
If you must start with RGB (like if you’re handed digital assets to work with), always convert to CMYK before submitting—and make manual tweaks to keep things looking great.
2. Soft Proof Your Files
Most pro graphics programs offer a “soft proof” mode—this simulates, right on your screen, what things will look like when converted to CMYK.
- In Photoshop: View ? Proof Setup ? Working CMYK, then View ? Proof Colours.
- Make colour adjustments until your PDF or image looks right in this view.
If you’re not sure how to do this, just ask! Simon is happy to preview or advise before you send your final file.
3. Keep Your Colour Space Consistent
Mixing and matching RGB and CMYK elements in the same artwork is tricky territory. You might see a logo in CMYK and a background image in RGB—making the switch during print can cause a jarring loss or shift in vibrancy and hue.
Top tip: Make sure all images and objects in your artwork are CMYK before you flatten or save.
4. Use High Resolution
No matter the colour, blurry prints are a nightmare! For crisp, clean results, make sure your file is at least 300 DPI (dots per inch) at the final print size (for photos, images, and artwork). Lower DPI files may look fine on screen, but will print pixelated or muddy.
5. Check Your Final File Format
For print, we recommend exporting your artwork as a PDF with fonts outlined and images embedded, or supplying high-res TIFF or JPG files. If you’re not sure, see our FAQ or ask us directly.
FAQs: Your Biggest Colour Questions, Answered
- Can you print in RGB if I send it that way? We always convert files to CMYK for printing. That’s why we say: convert it yourself first so you stay in control of how things look!
- My design uses brand colours—will they match exactly? Pantone® (spot) colours are the most precise, but standard CMYK gets very close for most colours. If it’s crucial, ask us about special inks or spot colours.
- Will my photo prints look duller than on my phone? Often, yes! Phone and computer screens are backlit and show brighter colours. The same image, printed, looks less luminous. Adjust brightness and contrast before sending.
- Do you provide printed proofs? Absolutely! For an extra fee, we can run a sample so you can check colours before we print the whole batch.
How Peterborough Print Can Help
We get it—colours can be confusing! If this all feels a bit much, just drop us a message through our Contact Page or swing by in person. Our experienced team can help you convert your files or give personalised advice before you commit to print.
And if you have lots of repeat or future projects, it’s worth talking to us about our artwork guidelines, proofing services, or how to get InDesign templates set up for worry-free results every time.
Quick Colour Mode Checklist for Submitting Artwork
- Is your work in CMYK? (Double-check before hitting send!)
- Is your resolution 300 DPI or higher?
- Have you soft-proofed to preview colour shifts?
- Did you flatten all layers and embed fonts?
- Are your files exported as high-res PDF, TIFF, JPG, or EPS?
Stick to these steps for vibrant, professional results—no nasty or dull surprises on delivery day.
Need More Help?
Head to our main site at Peterborough Print for more resources, or browse our FAQ section. And remember: our team is always just a phone call, email, or quick visit away.
Ready to press print? Make sure your colours are, too!