HDCAM SR from PT

[ergalthema]

I'm being considering for an audio mixer position for a tv show post house. The description has been pretty vague so far. It sounds like I would be dealing with pre-mixed, or at least rough-mixed, tracks. The only specific formats that were mentioned are HDCAM SR and Dolby E.

Could anyone describe the workflow that is probably used at this stage? Especially the types of connections that are used to interface PT with the VTR and encoder? Do you think they'll have a decoder for monitoring? Does the Dolby encoder send a data stream to a computer to create its master?

I think HDCAM SR can handle 12 audio tracks (and I think this company usually uses 7). And I don't know much about how Dolby E would be used.

Any info would be greatly appreciated.

[Chief Technician]

Originally Posted by ergalthema

Could anyone describe the workflow that is probably used at this stage?

You are probably going to be responsible for the mix and deliverables. HDCAM SR deliverables should be nothing more than a layback. Why Dolby E is involved I could not guess.

Originally Posted by ergalthema

Especially the types of connections that are used to interface PT with the VTR and encoder?

If you are using HDCAM SR, chances are good that you do not need to interface with a Dolby E encoder. You would use an RS-422 connection between the SYNC peripheral and the HDCAM SR for machine control. Audio I/O would most likely be AES.

Originally Posted by ergalthema

Do you think they'll have a decoder for monitoring?

If they need you to create Dolby E files, they either need a plug-in for encode/decode or the Dolby hardware. Either way, they should have a decoder, otherwise you cannot guarantee that any Dolby E encoded material is correct.

Originally Posted by ergalthema

Does the Dolby encoder send a data stream to a computer to create its master?

If you were using a hardware encoder, and wanted to record the stream, you could route it into Pro Tools (using the non-dithered mixer) and record the stream if necessary. The output of the Dolby encoder is suitable for transmission or layback, provided the VTR is configured properly. Information on VTR configuration is available from Dolby.

Originally Posted by ergalthema

I think HDCAM SR can handle 12 audio tracks (and I think this company usually uses 7).

Yes, HDCAM SR has twelve (12) audio tracks.

Originally Posted by ergalthema

And I don't know much about how Dolby E would be used.

I could only guess.

[ergalthema]

You are awesome!

If I may continue:

So, PT will (probably) connect to the sync peripheral via AES - one connection for audio and timecode? -edit: sorry, that makes no sense. Could you clarify how timecode vs audio is connected? (I understand that sync device would be connected to HDCAM via RS-422)

Are there many models of sync clocks that are used in major network TV post houses? Could you name any popular models?

Will the HDCAM tape always have the video/timecode on it before I receive it?

Any recommended reading for the detailed steps of setup/sync/layback? (I know Pro Tools pretty well, but I've mainly worked in the box up until now)

[ergalthema]

Also,

Any guesses to what might be used to QC levels? LM100? Dialnorm?

[Chief Technician]

Originally Posted by ergalthema

You are awesome!

Thanks!

Originally Posted by ergalthema

If I may continue:

So, PT will (probably) connect to the sync peripheral via AES - one connection for audio and timecode? -edit: sorry, that makes no sense. Could you clarify how timecode vs audio is connected? (I understand that sync device would be connected to HDCAM via RS-422)

The Pro Tools system you are using should have a SYNC peripheral attached to its HD|Core card. This will be either a SYNC I/O or a SYNC HD. The RS-422 port on the SYNC peripheral will be connected to the Remote I/O port on the HDCAM SR. This connection will transmit deck commands (play, start, stop, etc.) and timecode.

Originally Posted by ergalthema

Are there many models of sync clocks that are used in major network TV post houses?

There are several manufacturers of video reference (aka house ref or genlock) clocks (more commonly called generators).

Originally Posted by ergalthema

Could you name any popular models?

Popular manufacturers include (but are not limited to) Ensemble Designs, Evertz, Grass Valley, Miranda.

Originally Posted by ergalthema

Will the HDCAM tape always have the video/timecode on it before I receive it?

Most likely, however I am in no position to guarantee this.

Originally Posted by ergalthema

Any recommended reading for the detailed steps of setup/sync/layback? (I know Pro Tools pretty well, but I've mainly worked in the box up until now)

Chapter 50 and 51 of the v9 reference guide.

[ergalthema]

Thanks so much! I'll dive in to the manual now...

[ergalthema]

For laying back audio to HDCAM, which device is usually the master clock source?

[quadraphonics]

Originally Posted by ergalthema

For laying back audio to HDCAM, which device is usually the master clock source?

The HDCAM/sr is the master source. It receives video sync from a Video generator. When laying back, you can either feed video to your Sync IO/HD and clock to that or clock to AES from the deck.

Randall

[DJ Insomaniac]

Originally Posted by quadraphonics

The HDCAM/sr is the master source. It receives video sync from a Video generator. When laying back, you can either feed video to your Sync IO/HD and clock to that or clock to AES from the deck.

Randall

When clocking to AES from the machine, be aware that there may be a slight delay. You can test this/calculate the offset by recording a tone to tape, then recording that tone back into PT and compare the waveforms. We've been able to do this to lock to 23.98 tapes even though we don't have a Sync HD (just the older Sync IO).