Davinci synchronisation

Does any of you geezers know why when I put a video in video in Davinci, it’s ok at first, but then one video starts to lag behind the other.

Are the originals both identical fps? … and beware of what you are using to check reporting 29.7fps as 30fps … which can happen.

And if they are both identical … is the project also the exact same?

One is 60fps and the other is PAL which is 25? Not sure. But I thought the software would sort it out?

1 Like

It should sort … if the settings are correct …. and I’m scratching my head to remember where it’s set that makes a difference.

But, with 25 v 60 it would look right shit if the setting I’m trying to remember was incorrect.

So, the pic-in-pic … that’s the transmitted video and the main is the onboard?

Yeah that’s right.

The transmitted gets ahead of the onboard.

The transmitted has a few very iffy signal moments … and there’s definite potential for dropped frames. There may be dropped frames at other points too.

My guess is that’s the reason.

I’m guessing the transmitted is the 25fps … so it only takes 25 dropped frames to be a second out.

1 Like

Really? Hmmmm. That does make sense. I will read up on this. I would have thought that because I received static, that the video was still recording at the same bitrate. This could be tricky to fix. Thank you.

Simple test. Set the thing recording in the living room with perfect signal …. record a start “movement” and an end “movement” that can easily be seen to check sync, in a clip of the same duration.
If those stay in sync when overlaid in Davinci … then that backs up my hypothesis.
You can then do the other extreme …. a short flight way beyond reception limit (:thinking: if you dare) and do the same and see if the sync is lost despite only being a short clip.

2 Likes

Will do.

1 Like

For the first test - switching a light on at the beginning, and off at the end, would give frame accurate checking of sync. :+1:

1 Like