Understanding "Pass" in Vertical UV Wall Printing

In the world of inkjet technology, specifically for vertical wall printers, the term "Pass" is a critical parameter that defines how a digital image is physically rendered on a wall. It is the bridge between printing speed and visual fidelity.

What is a Printing Pass?

A "Pass" refers to the number of times the printhead carriage travels over the same horizontal area to complete the ink coverage.

  • Low Pass (e.g., 4 Pass): The printhead covers the area in fewer strokes. This results in the highest printing speed but lower ink density and detail.

  • High Pass (e.g., 12 or 16 Pass): The printhead overlaps the same area many times. This produces rich, vibrant colors and extremely fine details at the cost of slower production speed.

The Relationship Between Pass and Resolution

While DPI (Dots Per Inch) defines the potential detail of the printhead, the Pass count determines how those dots are layered.

  • 8 Pass: Generally considered the "Standard Mode." It offers an excellent balance of speed and quality for most indoor commercial murals.

  • 12 Pass: Known as "High-Resolution Mode." This is ideal for photorealistic portraits or murals that will be viewed from a very close distance.

  • 16 Pass: Used for "Fine Art" or textured 3D prints where maximum ink buildup and precision are required.

Masking and Error Correction

One of the most important technical benefits of a high-pass mode is error masking. In inkjet printing, individual nozzles can occasionally underperform or "clog" during a long print.

  • In a low-pass mode, a missing nozzle can leave a visible white line (banding) across the mural.

  • In a high-pass mode (e.g., 12 Pass), the software uses "interlaced" or "feathering" algorithms. Because the printhead passes over the same spot 12 times, the functional nozzles fill in the gaps left by any malfunctioning ones, effectively making small inkjet errors invisible to the naked eye.

Choosing the Right Pass Mode

The choice of "Pass" depends on your project requirements:

  • Outdoor Murals (4-6 Pass): High speed is usually preferred for large outdoor walls where viewers are standing several meters away.

  • Indoor Decor (8-12 Pass): Precision and color depth are paramount for home or office interiors.

  • Textured/3D Printing (12-16 Pass): Necessary for building up ink layers to create a tactile, three-dimensional effect.

Summary

For DXonJet users, mastering the Pass setting is the key to optimizing your workflow. While 8 Pass and 12 Pass are the most widely used settings, the flexibility to go up to 16 Pass ensures that the VPJet series can handle the most demanding artistic requirements without compromise.