Version 3.4.0.30 - May 7, 2026

Resolved issues
This version provides higher stability and fixes the following bugs:

• Separation rules: incorrect results with dark paper tints and opaque inks
  In special cases, separation rule calculations produced incorrect results when using dark paper tints together with opaque inks. 
• Visual gamut mapping: output ink priority ignored
  The new visual mapping of out-of-gamut inks did not always take the priority of selected output inks into account.

Note: OpenColor 3.4.0.30 cannot be installed on Windows Server 2016. Please refer to the list of supported operating systems.

Version 3.4.0.25 - April 16, 2026

Proofing:

Epson SureColor SC-P7300 / P9300
GMG OpenColor now supports the creation of proof profiles for Epson SureColor SC-P7300 and SC-9300 printers using the following proofing conditions:  

Epson SureColor SC-S9100 Jetcomp Proofing Media
New output conditions for the printer Epson SureColor SC-S9100:

Licensing change: Prototype proofing is now controlled via the licensing in GMG ColorProof (instead of GMG OpenColor), which reduces complexity and makes it easier to use. Accordingly, the output conditions for prototype printers are displayed by default in the database for all OpenColor systems with a “Proofing” license. 

Spot colors and CxF (proofing and separation)

Flexible spot color redefinition for digital workflows

The new spot color function Replace LAB Spot Color extends spot color handling beyond the limits of the previous color corrections. While the existing correction tool adjusts a measured spot color within the range of its original spectral model, larger target shifts could lead to inaccurate predictions of tints. The new function allows you to fully redefine a spot color by assigning a new LAB value. OpenColor generates a new spectrum from this target and recalculates all tints accordingly. Learn more

Spot Color IDs in Exported CxF Files
OpenColor 3.4 introduces unique IDs (UIDs) for spot colors and also their tints when exported as CxF. These stable, unambiguous identifiers allow third-party systems to reference spot colors without relying on names. Using UIDs improves integration reliability, enables safer synchronization with MIS/ERP and production systems, and ensures API connections remain stable, even if color names change over time. The CxF structure has also been optimized by introducing shared media references, each assigned a unique ID to reduce redundancy and improve consistency.

New Out-of-Gamut Mapping option in Separation Rules
A new option in the Separation Rules lets you control how out-of-gamut colors are handled.

In addition to the default Colorimetric (lowest ΔE00) behavior, you can now choose Visual (preserve appearance) to prioritize a better visual match instead of the lowest DeltaE. This is particularly useful for large format printing and smaller gamuts, while packaging workflows can continue using the default behavior. Since the default setting remains unchanged, existing configurations and tests are not affected.

Separation: Quality improvements

Print-to-Print profiles

• The new setting Fulcrums per Channel lets you tune the profile grid resolution. You can increase the number of fulcrums for higher accuracy when needed (e.g. for steep profile curves caused by a strong initial black start value and a high GCR level), or keep the default setting to ensure faster profile generation. Note that using more fulcrums increases calculation time.

• Improved Black Start accuracy in highlights
  We improved the calculation of the Black Start point during profiling, resulting in a more accurate black onset in the highlight range, enabling smoother tonal transitions and more consistent results.

• Improved black point handling
  Enhanced black point handling reduces unwanted color shifts when using non‑neutral (colored) black points - especially when Black Point Compensation is set below 100%. For more precise tonal control and more stable neutrals.
   
• Smoother separations when excluding overprints and applying TAC limits
  We improved how OpenColor handles excluded overprint combinations and total ink (TAC) reductions during separation. This results in smoother tonal transitions and more consistent gradients.
   
• Improved Print-to-Print gamut expansion (better use of target gamut)
  Print-to-Print gamut expansion has been enhanced to utilize the target color space more effectively, delivering stronger, more controlled saturation. For best results, ensure single-color channels are kept “pure” in the separation rule (and, if needed, boost spot/ECG single-color channels) to achieve consistent overall behavior.

RGB-to-Print profiles 

• You can now apply the following Separation Settings not only for Print-to-Print profiles, but also for RGB-to-Print profile calculations (RGB-to-CMYK and RGB-to-ECG):
  • Black Start
  • GCR (Gray Component Replacement)
  • Max Black
     

• Improved gray balance and black composition
  The updated GCR behavior builds neutrals with a consistent black (K) component from the highlights to the shadows, while the CMY separations remain clean and printable. This preserves the ability to perform manual color corrections in the CMY channels, even in areas where K is dominant. Gray components are shifted into K in a more controlled way, increasing neutrality and stability across the image. Even in color gradients and saturated color areas, a uniform CMY distribution is achieved, which simplifies retouching and enables more stable print results.

   

UI & UX improvements for manual profile creation

1. Renamed and consolidated profile actions
   Manual profile calculation actions have been consolidated and renamed to better reflect what they do and to make the workflow easier to understand:
   • “RGB-to-Channel Extender”, "RGB to CMYK"→ “RGB to Print”
   • “Multicolor-to-Multicolor” → “Print to Print”
   • “RGB/CMYK to CMYK” → “CMYK to CMYK” (“RGB” is moved to its own category)
2. Re-grouped profile actions 
   Profile buttons have been reorganized into two sections:
   • Recommended Profiles: the primary paths users should choose first 
     The two recommended profile buttons remain primary even if the user adds profiles.
     Create Calibration appears here when needed (secondary button).
     
   • Other Profiles: less common or advanced options.
     These buttons always remain secondary.
3. Smarter handling for “Print to Print”
   Print to Print is always enabled. If a user starts it without having added a separation rule, OpenColor shows a quick message explaining what’s missing. Optionally, users can create/add a separation rule directly from the message, reducing friction.
4. Dedicated “Finalize” section for publishing
   Publish is moved into its own Finalize section below the profiles. 
    

Resolved issues
This version provides higher stability and fixes the following bugs:

• RGB separation profiles – TAC issue
  Some RGB profiles exceeded the defined TAC (Total Area Coverage) value.
• Color Corrections - spot color dot gain changed
  In some cases, linear SCTV gradations did not stay linear after editing a spot color.
• Multicolor-to-Multicolor separation - incorrect Black start
  Some Multicolor-to-Multicolor separation profiles used a black start value that differed from the defined calculation settings.
• Calculating large numbers of separation rules - OpenColor crash
  In a few rare cases high memory allocation occurred, leading to an OpenColor crash.

• Separation rule cannot be calculated
  When using ink names with a German "Umlaut" in a target project, it was not possible to calculate a separation rule. Also in some very specific color combinations, the calculation stopped at 70% with the error message Pending results.