Accuracy with syncing multiple cameras

[jamalknight]

How accurate is the sync when recording using multiple cameras?

ie. If I want sync to be accurate in milliseconds, I would use a connecting cable or Genlock.

So my question is, does this software simply record from multiple cameras without any kind of accurate sync, or is there a function where each frame recorded matches each camera very accurately.

thanks

 

[deFrisselle]

AFAIK you have to set a delay per camera Basically a manual sync
Each camera is going to have its own natural delay due to the camera model and interface(s) to PC

 

[koala]

There is no sync mechanism in OBS across sources. OBS just reads the frame currently available from each source. The only sync I know of is that there is no tearing: OBS always reads a complete frame. It will not read the upper half of a frame and the lower half of the next frame, if the frame changed while reading the frame - instead, it will always read a complete frame.

 

[konsolenritter]

ie. If I want sync to be accurate in milliseconds, I would use a connecting cable or Genlock.

Syncing cameras by cable (usually high-speed models) does synchronize their shutters. That is totally independent from the question when the frames arrive in the cameras driver buffer in the pc. While there is no sync-in to OBS (OBS decides on its own "clock" when to read the frames), you may get synced frames in OBS if you go for a slow shoot rate (and use sync cable between the cameras), but there will be no guarantee at all.

If you want such guarantee you should go for specialized software, drivers and cameras for such purpose. Costs a little bit more than OBS... ;-)

 

[jamalknight]

Thanks for the response, very helpful!