Blackmagic & BM Timecode Accuracy (when will this issue be solved??)

[Keith Koby]

Sorry, I don’t know why it happens myself. I have a theory that when ref is provided to both devices, it doesn’t happen. However, most of the time we are syncing to incoming sdi…

The deck does beta sp and digi, so I think that the analogue components still want sync even when working with sdi source. Without the external ref, it wants to default to ndf even though a tape striped with df black and code is in the deck. It doesn’t make a lot of sense, but I think something here is messing with the communication between FCP, the card and the deck. The math is getting messed up or the signal is getting corrupted by one device asking for ndf…

I haven’t found a way to fix it permanently. You can check to see if will happen before laying back by hitting the “go to in” button in the ETT window. If it cues to the appropriate time code, you are ready to go. If it goes to the 3 sec and 18 frame offset, simply re-enter the time code in the “in” field, hit enter and hit “go to in” again. Check to make sure it cues appropriately this time. After re-entering the “in” time code, the problem usually clears up.

I’ve spoken with several people at Apple about this and no one has an answer.

kk

[Accountneedsrealnameupdate]

Just want to chime in that we’ve had exactly the same problems with 5 decklink bays here, it used to happen with the original Kona cards we had too but less frequently.
It wouldn’t be a problem if it was consistent but I can’t see any pattern to it at all.
We’re having worse trouble with D5 layoffs, sometimes they’re 3 or 4 frames off.
Glennser

[Michael Gissing]

I have had frame accurate inserts to dgi beta for over two years using both a 500 and now a 2000 Sony. However when I use HDCams (2000 and 1800 I get the one frame late problem which I compensate for by subtracting a frame from the in and out points in the edit to tape window.

I suspect it has something to do with reference video. I use a Decklink HD Pro card and I don’t think it locks to external SD color black when in HD mode. However I am sure it does in SD and there are no insert errors.

How many of you with this problem have house sync to the card and machines?

[Keith Koby]

My bet is that it has more to do with latency of the hd codec vs. sd codec you are using.

Go to A/V settings. Go to device presets. Duplicate your HD device control. Change the ETT latency setting from the default 4 to 5 frames. Then save your setup as a custom setup with the new device control.

Check to see if your laybacks are then consistently frame accurate.

[Sam Goetz]

We have house sync on all of our machines’ here and we still get the 1 frame off issue. Don’t think it’s a reference issue.

[Accountneedsrealnameupdate]

[Keith Koby] “My bet is that it has more to do with latency of the hd codec vs. sd codec you are using.

Go to A/V settings. Go to device presets. Duplicate your HD device control. Change the ETT latency setting from the default 4 to 5 frames. Then save your setup as a custom setup with the new device control.

Check to see if your laybacks are then consistently frame accurate.”

I’ve tried everything with the D5 with no luck, the odd thing is that there doesn’t seem to be a linear relationship between the playback offset and the delay on tape, I don’t have the numbers written down here but sometimes a difference of one frame in the playback offset would result in no change on the tape and sometimes one frame difference in the playback offset resulted in two frames on the tape. Oddly while I was playing around changing the offset it did seem somewhat consistent, only when I went to do a longer test did it go off again. I couldn’t get it dead on using the playback offset as it seemed as though I needed to enter a half frame offset and couldn’t do it, is there some trick entering less than a single frame?
I agree the delay could be the codec but why is it so random? I haven’t been able to tie it to restart, disk speed, other apps running or anything, all I want is consistency, I know I keep saying it but I have no problem with workarounds as long as they work, not knowing where fcp is going to dump stuff on tape is very frustrating.
Glennser

PS I’m testing FCP 6 right now, to early for results but my heart jumped when I saw this
https://forums.creativecow.net/readpost/124/866331?

[Alexander Falk]

with decklink drivers 6.3 it is a little bit better.

digital betacam still has 1 frame delay.
betacam sp is sync.
dvs sd-x-way is sync (hard disk recorder).

all machines are connected to the same house sync, the same sdi- / aes/ebu- / rs422-router

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4 x Avid Media COmposer Adrenaline 2.7
1 x Avid Media Composer 2.7
1 x Avid Symphony Nitris 1.6.3
1 x Avid DS Nitris 7.6

1 x Decklink HD Pro PCI-X 4:4:4
1 x Decklink HD Extreme
1 x Decklink SD Pro
2 x Decklink SD Extreme

1 x Workgroup Videohub
4 x HDLink