Display Problems

When a display misbehaves, diagnose in this order: routing, output mode, geometry, then content.

No Signal on a Display

Check:

  1. Display is enabled and not locked to wrong settings.
  2. Correct node (by name) and output channel.
  3. Correct output type (GPU/SDI/NDI®/Virtual).
  4. Node services are online.

Display Mode Not Supported

A display fails to come up when the output is set to a mode the connected display cannot accept. Check the display's capabilities:

  • Resolution and refresh rate. Confirm the display supports the configured resolution. WATCHOUT drives every display at the show's frame rate, so the display must accept that refresh rate.
  • Bit depth. Confirm the display supports the selected bit depth.

If any part of the mode is unsupported, the display is not created.

To see the mode each output is actually running, disable the node's displays and turn on the Splash Screen from the Nodes window. For each output it shows the channel number, current resolution, and refresh rate. The splash screen turns on only when no Runner is active on the node.

A common cause is a cable that cannot carry the configured mode. If 4K at 60 Hz exceeds the cable's bandwidth, the GPU driver falls back to a lower refresh rate, and the splash screen reports that lower rate. When you then enable the display, WATCHOUT enforces the configured mode and the output fails. Replace the cable or lower the mode.

For GPU displays, use emulated EDID where possible. It locks the reported capabilities so the mode stays valid even when the physical display is off or disconnected.

Display Renders Only Black

Assign a test pattern to the display to isolate the cause.

  • The test pattern shows — the output path works, so the problem is content-side. The content's presentation tier may not overlap the display's tier, or a display mask is hiding it. Check the presentation tiers and any display mask.
  • The test pattern is also black — the problem is the output itself. Re-check the mode above, the output type, and the routing.

Wrong Screen / Wrong Position

  • Re-check stage placement and display naming.
  • Use Frame in Stage and Frame All Displays.
  • Validate channel mapping in device properties.

Visible Seams or Warped Content

  • Revisit warp geometry and mask edits.
  • Verify soft-edge overlap quality.
  • Re-run projector calibration where required.

Interlaced/Color Artifacts

  • Confirm interlaced setting is intentional.
  • Verify color depth/color space settings per output path.
  • Compare with known test pattern media.

Tearing or Noise with Hardware Sync

When a node uses a Hardware Sync Group, some DisplayPort-to-HDMI converters do not cope well with the synchronized signal and produce vertical tearing or noise. The fault can be a specific converter, or a batch of converters with a particular firmware.

  • Test the output with a native HDMI or DisplayPort connection, or a different converter, to confirm the converter is the cause.
  • Use converters known to work with frame-locked output, and keep firmware consistent across units.

NDI® is a registered trademark of Vizrt NDI AB.

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