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-   -   Strange timecode problem (https://www.dvinfo.net/forum/general-hd-720-1080-acquisition/465205-strange-timecode-problem.html)

Tim Palmer-Benson October 6th, 2009 07:05 PM

Strange timecode problem
 
Tapes recorded on a Canon XHA1, injested into FCP 6:06 using an HV30 HDMI Black Magic card, are periodically losing time code. The tape stops, capture stops, then tries to reconnect and eventually picks up and goes on. Tapes recorded on another XHA1 and an XLHI do not exhibit this problem. I ran a head cleaner through the XHA1 and the HV30 and then tried a new test recording on the XHA1. The same thing happened after about 4 minutes! What could be the problem?

The recorded test tape plays back fine on the HV30 without interruption when I disconnect the HDMI plug and the Firewire cable. As you may know, this is the way you are supposed to capture HD recordings into FCP when you have a Black Magic card.

Adam Gold October 6th, 2009 07:07 PM

You don't pre-stripe your tape, do you? Could just be a tape dropout or dirty heads, I suppose. Sometimes a real cleaning at a service center works better than the cleaning tapes.

Edit: wait, did you say HDMI? HDMI doesn't have timecode. So now I'm even more clueless than usual.

Shaun Roemich October 7th, 2009 06:42 AM

Adam: Just a COMPLETE stab in the dark here but wouldn't HDMI still pass VITC timecode? It IS embedded in the video stream as opposed to Data Track timecode.

Tim Palmer-Benson October 7th, 2009 07:23 AM

Strange Time code problem
 
Just to get it straight here...I am using the HDMI output of the HV30 +++ I am using its firewire connection as a controller. You can do this with the HV30 by make specific settings in the HV30's playback menu. You set the firewire to SD DV Controller. You still get HD out of the HDMI output

Adam Gold October 7th, 2009 03:51 PM

Out of my depth here... my understanding has always been that sure, you get HD out of HDMI, but not TC of any kind, as HDMI is a display protocol not intended for editing. I could be totally misinformed.

Shaun, I assumed VITC was a relic of the analog age, but you obviously know a lot more about this than I do...

Nobody should listen to me on this one. I keep my workflow as simple as I can, because I'm a dope. Pop tape out of cam, pop into deck, capture via FW, no worries. Too much gear and too many steps make my head hurt.

BTW, my understanding is that there is no advantage to capturing tape via HDMI, as the data has already been compressed as it's written to tape, which negates what I've been told is the only advantage of HDMI capture -- it's uncompressed. HDMI is usually for live capture only. But the BM card may provide other advantages, although I've never been able to figure out what, other than a splitting headache. But that's because I am, as I said, a dope.

David W. Jones October 8th, 2009 06:21 AM

Since you did not provide enough information... Not knowing your capture or recorded settings, frame rate and such, I'll just take a stab in the dark.

24fps recorded on XH-A1 / being played back on HV30 which embeds 24p into 29.97 stream / being controlled by NTSC DV firewire timecode / into FCP 23.976 timeline???

Tripp Woelfel October 8th, 2009 06:31 AM

Reports I've read state that the HV30 can read the XH-A1 "native" 24f without the 29.97 embed even though it cannot record that way, so that wouldn't be a problem. In Premier Pro, XH-A1 24f footage captured from my HV30 reports it as 24fps. Now I don't think that guarantees that all is as it appears, but it seems to be.

Tim Palmer-Benson October 8th, 2009 06:33 AM

strange timecode problem
 
No, I am in 60i all the way, I am capturing in Black Magic Pro Res 1080i 59.94 = Apple Pro Res HQ. My Device control is set to Firewire NTSC
As I said, no problem with injesting tapes made on another HV30, two other XHAIs and one XLHI

So I am assuming there is some kind of problem with this particular XHA1....have run the cleaning tape through it twice for 5 secs each time

Does the time code getting digitally recorded on the tape in the same place as the digital audio or is it a different head? I hate to send back to Canon when I don't really know what the problem is.

Shaun Roemich October 8th, 2009 08:16 AM

Quote:

Originally Posted by Adam Gold (Post 1429223)
Out of my depth here... my understanding has always been that sure, you get HD out of HDMI, but not TC of any kind, as HDMI is a display protocol not intended for editing. I could be totally misinformed.

Shaun, I assumed VITC was a relic of the analog age, but you obviously know a lot more about this than I do...

My understanding is that VITC is still THERE but that most NLE's wouldn't NORMALLY go looking for it as most formats now use data code TC. I COULD be wrong...


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