About ColorUp Technology
Most designers have been taught to convert files to CMYK before sending them to press. It's sensible advice for traditional printing, but HP Indigo changes the rules. ColorUp is a workflow that asks you to do the opposite: submit your files in RGB and let the press handle the conversion. The results can be transformative.
Here's what happens behind the scenes. When an RGB file reaches the Digital Front End (the sophisticated computer that controls our press), it analyzes every pixel looking for colors that fall outside the standard CMYK gamut but inside the wider RGB color space. When it finds them, typically saturated blues, cyans, greens, and purples, it generates additional separation passes. Our press can run up to seven inks across sixteen separations, doubling up on cyan, magenta, and yellow to push color saturation beyond what four-color printing can achieve. The samples above show the difference: toggle between Standard CMYK and ColorUp RGB and watch the extra separations appear.
ColorUp isn't magic, and it won't improve every file. The DFE only generates extra separations when it detects colors that need them. A portrait photograph with natural skin tones won't benefit much, but NASA's space imagery, with those electric blues and saturated cyans, is exactly the kind of artwork where ColorUp shines. Europa's icy surface, the Webb telescope's cosmic views, and the Zombie Worlds poster all contain colors that would otherwise be flattened into a CMYK approximation.
Hold one of these prints up to the light and you'll see colors that seem impossible on paper. The blues have a depth and vibrancy that rival what you see on screen. It's not just brighter; it's truer to the original design intent. That's the promise of ColorUp: the color you imagined is the color you get.
Why Submit in RGB Instead of CMYK?
It feels counterintuitive. Every print class teaches the same lesson: convert to CMYK before sending to press. But that advice assumes a traditional four-color workflow. HP Indigo ColorUp works differently, and the colorspace you submit actually matters.
The reason is straightforward: CMYK files have already lost color information. When you convert from RGB to CMYK in Photoshop or Illustrator, out-of-gamut colors get mapped to their nearest printable equivalents. That electric blue becomes a duller process blue. That vivid green loses its punch. Once the color data is gone, we can't recover it. But if you send us the RGB file, the press can analyze the original colors and generate extra separations to reproduce them. It's the difference between working with the full recipe and working with leftovers.
Not every file benefits from ColorUp. If your design uses neutral tones, pastels, or colors well inside the CMYK gamut, you won't see a difference. But for high-saturation artwork, especially anything with intense blues, cyans, greens, or purples, submitting in RGB unlocks colors that CMYK simply cannot reach.
Best Practices
Design Considerations
- Design for saturation: ColorUp delivers its biggest impact on highly saturated colors, especially blues, cyans, greens, and purples that fall outside the CMYK gamut. Use vibrant colors intentionally where impact matters most.
- Reference the CIE diagram: Colors in the region between the sRGB and CMYK gamut boundaries are exactly where ColorUp works hardest. If your design relies on these colors, you'll see the most dramatic improvement.
- Manage expectations for neutrals: Skin tones, browns, grays, and muted colors typically fall inside the CMYK gamut already. ColorUp won't change these, and that's fine; they print well in standard four-color process.
File Setup Essentials
- Submit in RGB color mode: The file must be in RGB for the DFE to generate extended gamut separations. sRGB, Adobe RGB, and Display P3 all work; the press handles the conversion internally.
- Embed the color profile: Always embed the source profile (Edit > Assign Profile or Convert to Profile in Photoshop). This ensures accurate color interpretation during processing.
- Don't convert to CMYK first: Pre-converting to CMYK destroys the out-of-gamut color information that ColorUp needs. If your file has already been converted, going back to RGB won't restore the lost colors.
Substrate & Finish
- Brighter whites yield better results: Extended gamut colors depend on the substrate's white point. Premium bright-white stocks like Mohawk Superfine Ultrawhite maximize color vibrancy.
- Coated stocks preserve saturation: Gloss and silk finishes retain ink on the surface, producing more vibrant results than uncoated papers which absorb ink and reduce saturation.
Common Pitfalls
- Watch for gradient banding: Highly saturated gradients may show banding where extra separations are applied. Add subtle noise (1-2%) to gradients or use Photoshop's dithering options to smooth transitions.
- Proof before production: ColorUp results can vary by file. Always request a proof to verify the color enhancement meets expectations before committing to a full run.
Learn More
File Setup
ColorUp requires no special file preparation beyond submitting in RGB color mode. The HP Indigo press automatically generates extended gamut separations.
Gallery
Photography of printed ColorUp samples coming soon.
