IntelliTrap – Trap Settings Reference

IntelliTrap is a vector-based trapping engine that applies traps directly to PDF files before RIP processing. This guide explains the configurable settings found in the Trap Settings dialog box.


Get Trapping working in your system

The installer will have created the Trapping action as long as you are licensed for it.

If you need to create a Trapping action, follow these steps.

  • Launch the Navigator server.

  • Click Server Setup > Administrator Login…

  • Click Server Setup > Manage Workflow Actions…

  • Click the New Action button.
  • Select Trapping as the Workflow Agent.
  • Enter the desired name for the action. This is the name that will show up under the trapping icon.
  • Log into a Navigator client
  • The trapping action is now available for your workflows.


Use it in a workflow

The trapping engine traps PDF files. The action can be placed anywhere in a workflow before the RIP action.

Some jobs you may want to trap before imposition as single pages and others you may want to trap after imposition. For instance, you may want to trap your step and repeat jobs as single file and Step and Repeat after trapping. Other jobs may flow smoother through the trapping engine as a fully imposed job. The user has the freedom to create workflow that fits their environment.


Trapping presets

Configure a workflow to use a particular trap set automatically.  Choose your trap set at the drop down menu, shown below.

  • Click the plus button to open the editor and create a trapping preset.
  • Click the minus button to delete a trapping preset
  • Click pencil button to edit the selected preset.


 Put a pause in that workflow if you wish to view the traps directly after they are made.  If you don't wish to pause, or wish to pause for preview later (e.g. after rendering), then don't check "Pause After" here.


Trap Settings by group

 Distance

These settings define trap widths and intensity when trapping into specific object types or ink configurations.

  • Trap Distance
    Sets the base trap overlap distance (width) (in inches or mm).

  • Into Black
    Custom trap distance used when trapping any ink into black objects.  This trap distance is typically used for linework using black keyline contours, like in comics. When the trap distance is bigger than the black keyline contour, then the trap will be centered under the keyline.

  • Into Spot
    Custom trap distance for spot color objects.

  • Into Opaque
    Trap distance when trapping into opaque inks (e.g., metallics).

  • Into Image
    Trap distance used when trapping into image content.

  • Intensity
    Controls the strength (opacity/density) of the trap color as a percentage. Default is 100%.  The trap object is a new object containing the ink of the trapped object with a Blend Mode Darken applied. The default intensity used is 100%. However, an intensity of 100% can result in visible traps when the color difference between the two touching objects is too high. Reducing the intensity of the trap object will solve the problem.

  • Corners
    Defines the trap corner shape. Options:

    • Beveled

    • Rounded

    • Mitered

    • Square

Units

Sets the measurement unit used for all trap distance values.

  • Units
    Dropdown to choose either:

    • Inches

    • Millimeters (mm)

Pull Backs

Controls whether and how traps are pulled back (inward), useful for fine details and rich blacks.   

Pull Backs are often called stay-away-traps, cutbacks or keepaways. Pull Backs are needed when

objects, in rich black or rich spot color, are positioned on light backgrounds.

  • Rich Black is a composition of 100% black with a percentage of another separation. The result is a deeper look, making it more opaque.
  • Rich Spot Color is a composition of a dominating separation containing a percentage of any other separation. The result is a deeper and vivid color.

For instance:

  • Gold with yellow undercolor.
  • A green spot separation with an additional green separation.

In both cases the lightest separations are pulled back to prevent revealing the lightest separations at the edges of the rich black or rich spot color, in case of registration errors

  • Pull Backs
    Determines where pull backs are applied:

    • None - No pull backs

    • Allow All - the lighter separation will be pulled back from the edge of a rich black or rich color.

    • Flat Parts - a pull back is performed only when the resulting trap would have a flat (or solid, or 100%) ink.

    • 100% Black Flat Parts - the lightest separation will be pulled back from the edge of a rich black.  Pull backs will only happen in rich blacks and only when the edge is held by 100% black.

  • Pull Back Type
    Logic for which object(s) the trap pulls back from:

    • Single - Only pull back if just one colorant/separation needs to be pulled back.
      This avoids complex or uneven results — it’s an “all-or-nothing” safeguard.
      If more than one color would be pulled back, the trap is skipped.

      Use case: You want to avoid strange results where multiple separations are pulled back but not uniformly.

    • All But One - Only pull back if every colorant except one can be pulled back.
      This allows a pull back where most of the affected colors are adjusted — except one key separation.
      If two or more separations are left out, the pull back is skipped.

      Use case: You want to allow a trap as long as it doesn't mess up more than one important color (like leaving black untouched while adjusting CMY).

    • Both - pull backs are always allowed.

  • Pull Back From
    Restricts pull backs to specific content:

    • All - allows pull backs from over the top of object, regardless of color

    • White Only - Restricts pull backs to occur only when the object overlaps white — meaning the object must be sitting on a white background or a white-filled shape. 

  • Trapping Distance
    Pull back distance in inches or mm.

Behavior

Controls trapping rules for images, gradients, small gaps, and unknown traps.

  • Image Trapping
    Defines trap direction for images:

    • Automatic - trap engine will decide whether to spread or choke

    • Always Towards - traps will go into images

    • Always Away - traps will go from images into vector

  • Shading Trapping
    Trap direction for gradients (shading fills):

    • Automatic - trap engine decides

    • Always Towards - into shading fill

    • Always Away - away from shading

  • Ignore Gaps Smaller Than
    Skips trapping for gaps smaller than this threshold (in inches or mm).

  • Unknown Traps
    Behavior for unidentified traps, already in the PDF :

    • Ignore - keeps embedded trap data from unknown source

    • Remove - this is generally safe because the previously trapped area will then have a recalculated trap applied.

Advanced

Provides expert-level controls for trap logic based on visibility and color difference.

  • Trap Direction
    Determines how IntelliTrap chooses which object to trap into:

    • Least Visible - A first check will verify if trapping would solve the misregistration in both directions equally well. If not, the best trap is taken. If in both directions the resulting trap color is the same and both completely fix the misregistration error, then the color difference (Delta-E 2000 formula) will be compared against the luminosity difference of the touching objects. In case the color difference is greater than the luminosity difference, then a trap will be created where the color difference between the trap and the background is the lowest. In case the luminosity difference is greater, a trap is created towards the darkest area.

    • Always to Darkest - The L-value of the touching colors will be checked and a trap will be created towards the darkest color.

  • Minimum Color Difference
    Minimum color contrast (%) required to apply a trap. Default: 10%.

  • Visible Limit
    Threshold (%) for what’s considered a “visible” trap. Default: 55%.



Preview 

Traps can be viewed prior to output using our built-in viewer.  You can view both the trapped PDF and the trapped raster data if you wish.