Genlock Not In Sync When Using Long Cables

Symptom

The camera is receiving an incoming genlock signal, but third-party broadcast infrastructure (such as a switcher or video ingest equipment) indicates that the video does not align with the genlock signal.

Since this issue occurs when the video reaches third-party infrastructure, the camera does not indicate any errors due to this issue.

Explanation

If using long cables to connect the REDCAST Module to a genlock device or the video ingest point, the video may be delayed once it reaches the video ingest point.

For example, using a 1 km fiber optic cable to connect the REDCAST Module to a switcher creates a 2 km round trip for the video signal. This results in a round trip delay of about 10,000 nanoseconds. For 59.94 FPS, one pixel time is 6.73 nanoseconds, so the round trip delay is about 1485 pixels.

Potential Resolutions

Offset the signal in the broadcast truck using third-party infrastructure.

Offset the video signal in-camera to align it with the genlock signal. For more information, go to Set Genlock Offset.