View Full Version : Downconverted HDV options


Jiri Bakala
November 30th, 2005, 01:29 PM
I don't have the camera yet, so bear with me:

It seems that the consensus is that the camera/deck does not downconvert HDV to DV through its FW ports.

So if one shoots in HDV but needs to edit in DV (i.e. Mac Avid users at this point) then they have to capture from the analogue component outputs. BUT, if the capture setting is set to DV25 or better yet to 1:1 (providing the appropriate striped HDs are available), wouldn't the resulting footage be equal or better than if it were downconverted through the FW port on the deck?

Jiri Bakala
November 30th, 2005, 09:03 PM
Any takers?

Sean McHenry
November 30th, 2005, 09:47 PM
Thinking about this issue, it seems to me there would be additional A/D and D/A conversions happening that wouldn't happen if you could stick to a real digital workflow.

Luckily, the editors at my day job are telling me the analog footage from the BR-HD50 deck is beautiful. So, the D/A converters must be OK at least in the deck. I would think they are the same components in the camera.

Staying all digital would be effectivly lossless. There are conversion issues any time you go back and forth. Technically, it won't be HDV anymore either. It will be letterboxed or anamorphic, analog component video. Good looking video, but analog.

In the NLE it will be "digitized" and then go back out as potential analog from the edit. More conversions.

Sean McHenry

Jiri Bakala
November 30th, 2005, 10:26 PM
Well, that's what I am not sure about. If you downconvert from HDV to DV it's the usual DV compression (5:1) on top of going from 720 to NTSC. Now, if you only take the 'clean' NTSC BEFORE compressed to DV, even if it is analogue, wouldn't it still better? And if it's digitized at 1:1, it becomes a digital file and I would (like to) think that it would be better than DV. From this point on it stays digital, whether is goes to digiBeta or DV/DVCAM.

Just curious about the potential of this path.

Sean McHenry
November 30th, 2005, 10:34 PM
Oh, got your point this time. Yes. I would think you were right. Going from HDV to uncompressed SD component is what you are doing then. If you have a Mojo/Avid or other hardware based system, you could suck it in as uncompressed SD and go to town. Yes, that should give good results. Like I say, it will no longer be HDV so I wouldn't tell a client I was doing HD for them but I might be able to sell them on the idea that they are future-proofing their original footage you shoot for them today, as it will be available in HD for years to come.

In fact, it might be better than going beta. I'll have to ask the other Engineers at work what they think about that. I guess potentially, HDV, even in a component analog output should be better than beta. Unless there is a D/A issue with the cameras components or some HDV compression artifacts, it should be really good.

Sean McHenry

Linus Nilsson
December 15th, 2005, 07:46 AM
Am I understanding this correctly?

It is not possible to shoot in HDV with the GY-HD100 and then capture via firewire to Final Cut Pro to DV?

I know that this is possible with the Sony HVR-Z1E.

/Linus

Barry Green
December 15th, 2005, 01:28 PM
Not possible. The HD100 doesn't have a built-in downconvert capability. The Sonys do, the JVC doesn't.

Shannon Rawls
December 15th, 2005, 02:37 PM
amongst other things...reading this today....no downconversion is an ABSOLUTE deal killer for me. Far too often we need to make a straight to DVD project, but would like HD masters for whatever reason in the future. and we want to caputre it via FW.

- Shannon

Linus Nilsson
December 16th, 2005, 03:40 AM
OK, well then I got it clear, thanx!

My idea was to use a Powerbook G4 1.6 Ghz for pre-editing in DV and online on my G5, but maybe the powerbook is good enough to edit in HDV?
Any thoughts?

Tim Dashwood
December 16th, 2005, 08:50 AM
OK, well then I got it clear, thanx!

My idea was to use a Powerbook G4 1.6 Ghz for pre-editing in DV and online on my G5, but maybe the powerbook is good enough to edit in HDV?
Any thoughts?

I'm sure the powerbook 1.6Ghz would be fine. Remember, 720P HDV is actually a lower bit-rate than SD DV - so and hour of HDV footage will require less space than an hour of NTSC DV.

Giuseppe Pugliese
December 16th, 2005, 10:24 AM
Tim is your statement above really true or is it in theory? I found that about an hour of SD DV footage is is around 10 gigs... is HDV really only about 10 gigs of hdd space an hour? If so im shocked. I would love to seen numbers to back that up, if so that makes me a very happy man when i start to edit HDV projects :-)

Shannon Rawls
December 16th, 2005, 10:57 AM
Tim is your statement above really true or is it in theory? I found that about an hour of SD DV footage is is around 10 gigs... is HDV really only about 10 gigs of hdd space an hour? If so im shocked. I would love to seen numbers to back that up, if so that makes me a very happy man when i start to edit HDV projects :-)

Absolutely true! Amazing isn't it? High Definition Video file that's actually smaller then a regualr DV file of the same running time. Crazy! *smile*

I've never seen a DV25 file to be 10 gigs/hour. More like 12.5 to 13gigs an hour. HDV footage from the Sony Z1 is about 11.5 gigs per hour of footage.

- Shannon

John Mitchell
December 16th, 2005, 07:00 PM
amongst other things...reading this today....no downconversion is an ABSOLUTE deal killer for me. Far too often we need to make a straight to DVD project, but would like HD masters for whatever reason in the future. and we want to caputre it via FW.

- Shannon

Shannon - one good thing if you use Avid (and probably FCP as well) is that you can place HD footage straight into an SD timeline. So you can edit your project in HD and drop that edit into an SD timeline and you have both masters.

Now all we have to is wait for Avid to support all the HDV codecs.

Giuseppe Pugliese
December 18th, 2005, 04:15 AM
Wow that is truly great! thanks so much, this means i wont have to spend another $1,000 on a teribite aray!

I will still probobly have to upgrade my pc to a dual xeon processer pc to handle some major HDV editing but it still saves me some nice cash!

... any one know when Avid Xpress Pro will support the hd100u ?

Jiri Bakala
December 18th, 2005, 09:37 AM
... any one know when Avid Xpress Pro will support the hd100u ?
It does now (on PC) with the exception of 24p. On a Mac its support for HDV is planned for mid 2006.

Giuseppe Pugliese
December 18th, 2005, 01:15 PM
ohh well i need the 24p so i guess ill just wait :-)