OCS
OpenColor Standard

OCS for Print Production

OCS bridges the gap between digital color specification and physical output by making substrate intent part of the color identity.

Substrate-Aware Color

A color on coated paper looks different than the same color on uncoated stock. OCS accounts for this by including a substrate code in every color ID. When you specify OCS-7055-025-C, the "C" tells the printer this is intended for coated stock.

To see the same color defined for uncoated paper, look for OCS-7055-025-U. The LCH values are adjusted to account for ink absorption and surface texture differences.

How Substrates Shift Color

SubstrateLightness ShiftChroma EffectNotes
Coated (C)None (reference)100% (reference)Baseline. Most saturated print output.
Uncoated (U)-3 points82% of referenceInk absorbs into fibers. Softer, warmer feel.
Textile (T)-2 points72% of referenceVaries significantly with weave and fiber type.
Film (F)+5 points88% of referenceBacklit use increases perceived lightness.

Using the Substrate Simulator

The Substrate Simulator previews how any OCS color appears across all six substrate types. Use it during the proofing stage to set expectations with clients before physical samples are produced.

Proofing Workflow

  1. Select colors from the library using the Coated (C) substrate as your starting point.
  2. Use the Simulator to preview the target substrate.
  3. Note the adjusted LCH values and provide both the base ID and the substrate-specific variant to your printer.
  4. Request a physical proof on the actual substrate for final approval.

Specifying Colors for Print

When handing off to print production, include:

  • The full OCS ID (e.g., OCS-7055-025-U)
  • The LCH triplet for reference
  • The substrate type and any special stock requirements
  • A note if the color is out of sRGB gamut (the print gamut may still support it)