Instruction Paper: Using Alwan ColorHub with ChromaChecker

Objective: To provide clear instructions for configuring Alwan ColorHub to align with your ChromaChecker-verified printing conditions. This guide will help ensure printer stability, enable reliable troubleshooting, and minimize production waste.

1. Introduction: The Core Principle of Alignment

The primary goal of integrating Alwan ColorHub with ChromaChecker is to achieve a stable, predictable, and efficient print environment. This is accomplished by ensuring that the Output ICC Profile configured in Alwan ColorHub precisely matches the actual, measured printing condition of your press, as verified by ChromaChecker.

When this alignment is correct, you will benefit from:

• Predictable and repeatable color separations.

• Significant ink savings through intelligent GCR (Gray Component Replacement).

• Excellent color matching and brand color consistency.

• Elimination of common printability issues (e.g., over-inking, drying time, registration).

• Consistent and reliable output for your press operators.

ChromaChecker defines and monitors your print condition, while Alwan ColorHub uses that definition to optimize every incoming file.

2. Configuration Settings in Alwan ColorHub

The following sections detail the key settings within Alwan ColorHub. Each setting includes an explanation of its purpose to provide insight into its function.

2.1 Input – CMYK Profile

This setting defines the color meaning of the CMYK values in incoming files.

• Configuration:

  • For Maximum Ink Savings: If your primary goal is ink optimization, set the Input ICC Profile to be the same as your Output ICC Profile. In this scenario, do not enable the "Use Embedded Profile" option. This standardizes all incoming files to your target print condition.

  • To Honor Customer Intent: If your clients provide files with high-quality embedded ICC profiles and expect them to be used, you can enable the options to Use Embedded ICC Profiles and Rendering Intents. This is for workflows where you trust the client's color management.

  • For Safety and Consistency: If you do not trust the quality of embedded profiles from customers, disable the "Use Embedded Profile" option and assign your standard Input ICC Profile (e.g., GRACoL 2013). This protects your workflow from poorly constructed files.

• Purpose: This setting is the foundation of your color management strategy. It determines how Alwan ColorHub interprets the color information in a customer's file before optimizing it for your press.

2.2 Output – TAC (Total Area Coverage)

This setting controls the maximum amount of ink applied to any area of the print.

• Configuration: The recommended TAC for a profile like Alliance_UC_UV is 276%. These values are a safe starting point and can be adjusted to match your specific press conditions or profile specifications (e.g., reducing to 275%). You do not need to change the default values to begin.

  • Note: If you want separations similar to a basic ICC conversion (like in Photoshop), select "Use Output Profile Separation". However, this will bypass some of Alwan’s advanced optimization.

• Purpose: Alwan ColorHub’s TAC control is dynamic and intelligent. It analyzes each object in the PDF (including its size) and regulates ink coverage accordingly. This is far more advanced than a simple profile conversion. The provided settings are already optimized for strong ink savings, limiting risks like poor drying or paper distortion.

2.3 Output – Purities

These settings are color management exceptions designed to improve printability.

• Configuration: The “K + Secondary Overprints” option can be enabled or disabled based on your preference. It will not have a major impact on most jobs.

• Purpose: This powerful feature targets vector elements designed with pure black (K) plus secondary colors (Cyan, Magenta, or Yellow) set to overprint. When enabled, Alwan ensures no additional process inks are added to these specific color builds. This helps reduce ink contamination on press and prevents potential registration issues for fine vector elements.

2.4 Output – Advanced Settings

These settings offer finer control for specific production challenges.

• Max DVLP Grid Resolution

  • Configuration: A setting of 11 points is standard and processes files quickly. A setting of 21 points can provide more refined color transitions but is not mandatory. Modern computers can handle either setting without noticeable delays.

  • Purpose: This controls the size and precision of the DeviceLink profiles that Alwan creates on-the-fly. Unless you encounter issues with subtle gradients or color transitions, the default setting is sufficient.

• Dynamic TAC (DTAC)

  • Configuration: This feature is off by default and should only be enabled if needed.

  • Purpose: DTAC is a smart function that automatically lowers the TAC for large, solid areas of high ink coverage (like a black background) while maintaining full TAC for small detail areas (like the pupil of an eye). This improves printability and reduces drying issues on jobs with large ink solids.

• Vector Overprint

  • Configuration: Leave this option unchecked by default.

  • Purpose: This is a specific troubleshooting tool. Enable it only if you observe unexpected visual artifacts in vector objects that are set to overprint. It provides a solution for rare files where ICC-based color management interferes with overprint behavior.

2.5 File Options – Rasterization

This section allows Alwan ColorHub to pre-process complex files before they reach your RIP.

• Configuration: Set the resolution based on your output device.

  • 300–500 dpi: Sufficient for most digital printing.

  • 900 dpi: Recommended for high-resolution offset printing to achieve the smoothest results.

• Purpose: Modern design files often contain complex live transparencies and overprints that older or less capable RIPs cannot process correctly. By letting Alwan rasterize these complex elements, you ensure that what you see on screen is what will print, avoiding unexpected results at the RIP stage. This is especially valuable in environments with multiple or varied RIP technologies.

3. Final Recommendations and Key Takeaways

1. Start with a Solid Foundation: The configurations provided by your integrator are optimized for standard coated and uncoated workflows. Use them as your starting point. It is common and recommended to create multiple queues over time, each tailored to a specific substrate, printing device, or customer requirement.

2. The Golden Rule: The Output ICC Profile must match your actual printing condition verified by ChromaChecker. This is the single most critical factor for success. If the profile does not match the press, you will see color shifts and unexpected results. This is not a software bug but the expected outcome of a mismatch. Following this rule unlocks the full power of Alwan ColorHub and ensures a stable, cost-effective print workflow.