View Full Version : Am I using correct workflow HDV to SD?


Dennis Robinson
May 5th, 2007, 02:26 PM
Hi,
I am shooting HDV720/25p footage and editing in FCP 5.1.4. I mainly produce TV commercials and have just started adding text an graphics on a HDV timeline.
To downconvert, I simply create a new SD sequence and drag the HDV sequence into the new SD timeline and it appears to work fine.
After rendering I print to video on a new tape ready for broadcast.
The question is: am I losing quality in the text by adding it in the timeline before downconverting this way or should I add the text in the SD timeline instead. I have tested both ways and really cant see a difference and it is easier to produce the whole commercial in HDV.
I would also like your views on whether i should use Compresser from the HDV timeline and create an 8 bit uncompressed movie that can be imported into a new SD timeline.
Thanks for your views.

David Knaggs
May 5th, 2007, 05:48 PM
Hi Dennis.

Here's a thread on HD to SD downconversion by someone whose opinion I really respect:

http://www.dvinfo.net/conf/showthread.php?t=63494

Dennis Robinson
May 6th, 2007, 04:05 AM
Hi Dennis.

Here's a thread on HD to SD downconversion by someone whose opinion I really respect:

http://www.dvinfo.net/conf/showthread.php?t=63494

Thanks David. It is a great link, however I am unsure what type of sequence I need to create to bring the 10 bit uncompressed clip into. Is it a standard Pal DV anamorphic timeline or a 10 bit uncompressed timeline. Remember, I need to print to tape for broadcast and not DVD so much.
There is no doubt the clip looks better as a 10 bit movie, mainly the colour but on the new SD timeline I cant see much if any difference. Any ideas are great.

David Knaggs
May 6th, 2007, 10:36 AM
Thanks David. It is a great link, however I am unsure what type of sequence I need to create to bring the 10 bit uncompressed clip into. Is it a standard Pal DV anamorphic timeline or a 10 bit uncompressed timeline. Remember, I need to print to tape for broadcast and not DVD so much.


Select the "Uncompressed 10-bit PAL 48 kHz" option in the Easy Setup, then create a new sequence. Definitely do NOT select any form of DV-PAL, because DV is a codec and will therefore add compression.

And that brings me to another question, concerning how you are printing to tape. Do you have a Blackmagic or AJA Kona card and a Digital Betacam deck? Or are you going out through a FireWire to a JVC camera or deck? (And then take your mini-DV tape to a facility to get it transferred to a Digital Betacam tape?) I'm assuming that your final delivery is on Digital Betacam tape. Let me know if I'm off the mark here.

Because, if you're going back out to the camera, the VTR section of the camera manual (page 90) indicates that it only supports HDV and DV formats. So I guess this would mean that it would add a DV compression to your previously uncompressed footage before it even gets close to a Digital Betacam transfer (and remember that Digital Betacam will add its own compression as well). So, if you only have the camera option available to you, I reckon the best way (least amount of compression) might be to simply export your original HDV timeline via Compressor into Uncompressed 10-bit and store that Quicktime on an external hard drive. Then take the hard drive to a transfer facility where they can (hopefully) hook up the drive to one of their edit suites and print directly to Digital Betacam tape.

Dennis Robinson
May 6th, 2007, 04:51 PM
[QUOTE=David Knaggs;673652]Select the "Uncompressed 10-bit PAL 48 kHz" option in the Easy Setup, then create a new sequence. Definitely do NOT select any form of DV-PAL, because DV is a codec and will therefore add compression.

And that brings me to another question, concerning how you are printing to tape. Do you have a Blackmagic or AJA Kona card and a Digital Betacam deck? Or are you going out through a FireWire to a JVC camera or deck? (And then take your mini-DV tape to a facility to get it transferred to a Digital Betacam tape?) I'm assuming that your final delivery is on Digital Betacam tape. Let me know if I'm off the mark here.

Hi David,
I am printing to tape through firewire to the JVC camera. I then take the tape to a facility that dubsats the completed commercial to the TV channel. It never gets converted to Digibeta etc.

David Knaggs
May 6th, 2007, 10:07 PM
Hi Dennis.

Thanks for the info. And neglect everything I was saying about Digi Beta!

I am interested to know of your final results in printing the Uncompressed PAL sequence to the camera tape. I've only ever gone out to tape (camera over FireWire) from a DV PAL sequence and an HDV 720p24 sequence (and the taped HDV looked great!). So knowing how the Uncompressed PAL option performs would be useful info.

Sean Adair
May 7th, 2007, 03:27 PM
"I am printing to tape through firewire to the JVC camera. "
If you are delivering on DV-tape, then nix the whole uncompressed step - there won't be any gain, only the time and pain...
Use compressor to produce the PAL master in DV-PAL, then output via FCP to tape directly.
HOWEVER, you could see some real gains by changing your delivery and the workflow to that point. Since these are commercials, and short form I presume, you could put 30 seconds of less compressed footage on a DVD data disc. Even DVC-PRO50 SD will be a noticeable improvement, especially with graphics, since the color space dosn't get compromised.
You'll have to check with the facility in what they can handle, but AIC, Photo-JPEG, and 10 bit uncompressed will produce incremental improvements.

"I then take the tape to a facility that dubsats the completed commercial to the TV channel. It never gets converted to Digibeta etc."
If not digibeta, it's some other high end mastering format... that's what the facility is dubbing to. Someone there might be able to help you optimize the delivery method.