Genlocking and latency is very minimal: “as little as 1 frame” is stated in the User Guide. It is approximately between 1.5 and 2.5 frames (the actual amount can vary slightly within this range, depending on several factors).

One factor depends on the model of TriCaster. For example if you’re using a Mini HDMI, because of the HDMI connection the latency will be higher than if you were using SDI. If you’re running entirely in SDI, using the same video format, all cameras are locked via genlock and you disable the TriCaster’s frame syncs (possible with the 8000 or 860/460 with Advanced Edition) then I would expect to see around one frame of latency. If the TriCaster’s frame synchronisers are engaged then this can increase to between 1-2 frames, depending on the video timing.

Other parts of the production chain can affect signal latency. For instance, we have found that the make and model of camera(s) and indeed display(s), can be a significant factor when measuring latency. For example at trade-shows such as NAB & IBC ‘big screen productions’ we have minimised high latency by ensuring that:

1) We use as low latency cameras as possible (different cameras have significant differences in latency)

2) We disable as many settings in the cameras as possible. "Good" cameras will reduce the latency if you disable scalers, motion stabilization, etc...

3) We make sure that the displays we are using are low latency. Unfortunately most modern displays add quite a lot of latency as well :(

4) We disable all of the scalars in the displays and run as close to "native" resolution as possible. Each scale and processing step adds latency. Many new displays have a "computer game mode" that is specifically designed for running in low latency mode.

Causes of Latency

  • Attaching a USB drive to the TriCaster during a live production can cause frames to drop from the Main Production. 
  • Or copying videos across media/network drives. 
  • Or not genlocking cameras

How to measure latency through a device

This will allow you to see the original timecode on a computer screen and the timecode difference on the output monitor, which is receiving the signal through the equipment being tested.

  1. Set up a video camera inputing to TriCaster.
  2. Set up TriCaster outputing to a monitor.
  3. Set up a computer running a looped timecoded video and place next to monitor.
  4. Point the video camera at both and take pictures with a photo camera.
For reference, here’s the timecode video we use at 1920x1080, 29.97: