Overview

The “Show Missing” feature in the VISU PMM Wizard (Gamut Measuring window) is a visual diagnostic tool.

It helps identify patches that will not be used in the final profile calculation, even though they may have been measured.

What does “Show Missing” mean?

When enabled, “Show Missing” highlights patches that are excluded from profiling, including:

• Missing patches → not measured at all
• Unexpected patches → measured values are invalid or outside the expected range
• Rejected patches → measured, but excluded due to smoothing or quality issues

These patches are not used in the final profile generation, which is why they are flagged.

Important clarification

This feature often causes confusion:

Patches shown as “missing” are not necessarily unmeasured.

In many cases:

• The patches were measured correctly
• The measurement process has not changed
• The system is simply showing that they are excluded during profile creation

This behaviour has been part of the gamut engine for a long time. The difference is that it is now visible to the user.

Automatic behaviour

The VISU PMM Wizard will automatically assist when issues are detected:

• If missing or clearly incorrect patches are found:
  • A warning is shown
  • The “Show Missing” view is automatically enabled

This ensures you can immediately see which patches are problematic.

When should you take action?

You should review highlighted patches if:

• A large number of patches are flagged
• You see clusters of missing or unexpected patches
• The resulting profile quality appears incorrect

Typical causes include:

• Measurement errors (misreads, device issues)
• Incorrect chart alignment
• Lighting or scanning inconsistencies
• Corrupted or partial measurement data

When can it be ignored?

In many cases, no action is required:

• A small number of excluded patches is normal
• The smoothing process intentionally removes outliers
• Profile quality is usually not negatively affected