HDCAM SR SRW 5500 and LTC issues

[Doglett]

Hiya

First post, so if this is in the wrong place...tutt

We're delivering a series for Sky 1 on HDCAM SR, HD CAM, DIGI and DVD.

We did the first run of deliverables a couple of nights ago and, in a single pass, made the following copies of the HDCAM SR master, the LTC lopping onto the next deck each time.

1x HDCAM SR
1x HD CAM
1 x DIGI
Various clean and BITC dvds.

Checking these back the next morning, I found that the time code was wrong on the HDCAM clone and Digi. There was also been a copy made of an international HDCAM version the same night and this too was wrong.

Effectively we discovered that somewhere between the HDCAM SR record deck and the HD CAM deck (an HDW D2000) the LTC was slipping by 4 frames. So on any copy made on the HDCAM, the program would come in at 09:59:59:21 instead on 10:00:00:00.

Furthermore, our online editor reported a similar issue when he captured a snippet back into our Nitris to check video levels. He found that even on capture off the same HDCAM SR deck (The one before the HDCAM in the chain.), everything was shunted back by 4 frames.

Does this make sense? Is it an easily changed setting on the SR deck?
It was a rental company one and maybe if it's factory reset the next time we hire it this won't occur?

It would be really good to be able to use all available machines and make deliverables in one pass!

I appreciate any help!

Thanks,

James

[huub]

very well possible that someone on this forum will know, but it iiiiis an audio forum

[awalk]

Hi
Take a look at this thread on the DUC HD-Cam SR: Laying Back Next week Am I missing anything. - Digi User Conference
There is a setting on the deck explained in the thread that you should change
Good luck!

[Doglett]

Huub... I was led here by Google whilst searching for an answer...
Ha ha.. I have been DECEIVED!
(Our 5.1 lay off was fine incidentally, although I dare say there will be audio questions in future. :-) )

Awalk... Ahh. That thread is the second time I've heard about the infamous '618' menu option. I'll do a test with that setting when we have the deck in next. Thanks.

J

[hummer]

Indeed, menu #618 is what you need to change. For laybacks, it should be set to "input" and for capture, it should be set to "output". You are probably not going to be able to layback to any other machines through the hdcam because of the 4 frame delay.

Another thing to check is that LTC phase=LINE in the PHASE SET menu. Shift+diag, shift+maint exec, others check, alt, phase set to get to that menu.

Ahhh the hdcam sr decks. Can't live with em, can't throw them away cause they're better than D5!

[hociman]

Originally Posted by hummer

Indeed, menu #618 is what you need to change. For laybacks, it should be set to "input" and for capture, it should be set to "output".

I did some testing on Friday with our SR deck, and found that if menu #618 was set to "input" that audio I printed was in sync on the tape. When I captured the audio back into Pro Tools, menu #618 was still set to "input", and the audio captured in Pro Tools appeared on the timeline where I expected it to. I did this testing with a beep track, and verified the results by loading the audio off of tape into Final Cut and observing the beeps occurring at the proper timecode address.

Is my testing methodology flawed? I have seen the 4 frame offset in the past, but with menu #618 set to input I can't make it happen again.

Thanks for reading!

[thierryd]

Hi Jonathan,

My guess is your SR deck was probably still in edit mode (some tracks were selected to be record-ready) when you captured the audio back into PT...
VTRs behave differently in edit mode (i.e. looking at video input for ref sync) than in PB mode (looking at the ref input for ref sync). Also the 4 frame offset of HDCAM (SR) decks is influenced by edit/PB mode.

Greetings,

Thierry

Originally Posted by hociman

I did some testing on Friday with our SR deck, and found that if menu #618 was set to "input" that audio I printed was in sync on the tape. When I captured the audio back into Pro Tools, menu #618 was still set to "input", and the audio captured in Pro Tools appeared on the timeline where I expected it to. I did this testing with a beep track, and verified the results by loading the audio off of tape into Final Cut and observing the beeps occurring at the proper timecode address.

Is my testing methodology flawed? I have seen the 4 frame offset in the past, but with menu #618 set to input I can't make it happen again.

Thanks for reading!

[hociman]

Hi Thierry,

Thank you for responding. I went back and revisited this test. I still had the same results. I made certain that the deck had no tracks armed, and I record inhibited the tape as well. When loading the audio into Pro Tools off of the tape, I did not have to apply any offset.

Perhaps that product manager from Sony told me the super-secret way to never have to worry about an offset when he and I spoke at NAB? Once would be a fluke, but twice means there has to be a reason. Can the deck be in record ready mode even when no tracks are armed? If not, then I am not experiencing this offset issue. The other flaw in my tests could be that I am doing something wrong, but if that's the case, I'm doing it wrong consistently.

I know this tape machine does not playback audio while jogging as well as a digi beta, but even when I jog the tape real slow the 2-pop appears on the frame that it should when jogging forward.

If anyone else can chime in as to what I might have discovered please do. It all looks good to me here, but maybe I'm not looking in the right places?

Thanks for reading,

[TVPostSound]

Jonathan,

There are some machine profiles (for SWR machines) floating around that have the
4 frame offset built in? I think they were part of PT 7.3/7.4









.

[hociman]

Originally Posted by TVPostSound

Jonathan,

There are some machine profiles (for SWR machines) floating around that have the
4 frame offset built in? I think they were part of PT 7.3/7.4

TVPostSound,

I checked the profile, and there is no offset built into it. The offset value appears as zero when I load the profile for modification. I will scrub the 2-pop when we do the layback to verify sync.