Blackmagic URSA question

[kwingyiu]

I wish to enquire a question regarding using Blackmagic URSA.
Does anyone come across any problem with video and audio mismatch when using this camera?  There is a delay of the video or audio.
Someone mentioned to me that using the internal card storage (CFast Cards) would cause this issue because there is an issue of saving large files.

[John Brawley]

Hello.

What kind of delay are you seeing ?

I have only seen delays introduced as errors sometimes when trying to transcode to other formats.

I have never seen a delay of audio and video and I've shot hundreds of hours with all of Blackmagic's cameras including the Ursa and Ursa Mini.

JB

[kwingyiu]

Thanks JB for your quick reply. I am glad to know this.
We set up a studio for filming teaching material. The guy who set the camera up told us that there was an issue with this camera. So he connects iMac to this camera and runs QuickTime Player to record from SDI output.  The external mic is connected to an amp then to the camera.
I don't understand why we do not store the files directly on the CFast card. We could use a card reader to transfer the files. Do you think this is more direct and makes sense?
Based on your experience of using this camera, can you suggest the best workflow from filming to editing?
Many thanks.

[John Brawley]

That sounds very odd.

The ONY way I know of to get this to happen when recording to internal media is if you have the PROJECT frame rate set to say 25 and the SENSOR frame rate not set to "MATCH" but to 25.

So if I'm recording for a 25 fps sync project the PROJECT frame rate should be set to 25 and the SENSOR frame rate should be set to MATCH.  It's posisble to also set the sensor frame rate to 25 but perversely this will make your sound out of sync on longer takes.  I had a situation in a car where I had the wrong settings, the sensor frame rate was set to 25 instead of "MATCH" for a 25 frame job and we recorded a 40 min ProRes clip... at the end of 40 mins the sound was out of sync by 19 frames from the start where it was in sync.

It might be worth checking those setting as it's an easy mistake to make.

JB

[kwingyiu]

Thanks for your tips.
Can i ask one question here?
Could i connect my BlackMagic to an iMac and use it for for monitoring and capturing the video? How is it set up? Do i need an interface like BlackMagic Intensity Extreme?