Jump To Uncompressed...

Hello. I have just upgraded my computer to the new 2.7 dual, with tiger. I want to add the capability to work with uncompressed DVCAM footage. The goal is to output to DVD or to digibeta. Can anyone recommend the better way of getting there. My current camera is DVCAM; I have 2 (250 gig each) external (400) firewire drives to capture media. I usually work on no more than one big project at a time between 60-90 minutes each in length. I have been using the dsr11 deck, but I expect that no longer will work as a deck for capturing uncompressed. I also want to be able to create dubs of identical timecode from my field tapes.

Thanks for your guidance.

1. If you're working in DV (DV or DV Cam = same animal) and importing as DV and editing in a DV timeline, then I don't see a reason why you would want to edit in uncompressed. Export final edit uncompressed for DVD yes, but capture, convert to uncompressed, and edit uncompressed? You'll also need about 8x the storage space for uncompressed vs. the same running time in dv. And then there's the drives. 500GB probably isn't near enough for long format edits. An umcompressed 90 minute playout for DVD will cost pretty close to 200GB all by itself.

2. Your DSR-11 connected via firewire is fine for anything shot on DVCam. There are some timecode and general functionality limitations with the DSR-11, but otherwise no difference in quality to the bigger machines.

3. To make dubs from the field tapes, just record them from the camera onto the DSR-11 via firewire.

4. External fw drives huh? Well, that will ignite a discussion here if anything will. At the minimum, buy an additional pci firewire card to run the drives from. Keep the main firewire bus free for the DSR-11.

hth,
Clay

Clay is right. There's zero advantage to uncompressed capture unless you have the money for a deck with SDI, a SDI capture card, big drives and don't have time to render the DV as uncompressed with a smoothing filter on it at the end of production. A smoothing on the chroma is indeed the only difference you'll get from an uncompressed SDI capture over a firewire one. For 75% of video, it's probably not worth it. If you want to see the difference though:

[www.nattress.com]

Will tell you all you need to know (and more).

Graeme



[www.nattress.com] - Plugins for FCP-X

<<<that will ignite a discussion here if anything will.>>>

Will Not!

Actually, when we got our FireWire card one of the operators started capturing uncompressed SDI (AJA IO) to a well-behaved FireWire drive and it went with no apparent damage.

Surprised a number of us, but I still wouldn't bet the ranch on it.

<<<There's zero advantage to uncompressed capture>>>

Actually, several people got after me for saying that earlier. Isn't it true that complex effects damage the video less if you do them in uncompressed land than in DV, even given the same pictures?

Koz

Rendering DV as uncompressed can reduce damage, but you don't have to capture the DV uncompressed to render it uncompressed.

Graeme



[www.nattress.com] - Plugins for FCP-X

Yeah, I've tried to improve the quality of stills I export from my thesis film by capturing short segments in Uncompressed 8-bit (boy those files are fat), then exporting the stills. I couldn't see much difference from the stills exported from footage captured in DV NTSC. I guess it's the limitation of the original footage. Capturing in DV NTSC from a Mini-DV/DVCam is a practically lossless re-creation of the footage, isn't it?

Well, I appreciate your responses.

There is much to read up on on Graeme's site. One follow-up question if I may (at the risk the answer is buried within the information referred to above): how can you capture video that is compressed and then uncompress the same compressed material, and somehow increase the quality of the image or reduce damage when applying special effects? As an analogy, if I capture (convert) a low res image from a high res image, how can I upscale that same (low res) image back into a high res one?

Also, what is the rationale for adding on an additional pci firewire card to run the DSR 11 deck?

If I need a tape master for the finished uncompressed version, is the only option to output to a digibeta deck instead? Would I need a special card, or other hardware enhancements to do this?

Last, if I do not capture the DVCAM video as uncompressed, how do I uncompress it before applying filters or special effects, or final output?

I will likely have more questions after reading the printed material. Until then, thanks to everyone for your invaluable knowledge.

<<how can you capture video that is compressed and then uncompress the same compressed material, and somehow increase the quality of the image or reduce damage when applying special effects?>>>

You can't do special effects on compressed material. FCP has to form an uncompressed sequence from whatever you present, do an effect, and then recompress it. The fewer times it has to do that, the better.

Ideally, of course, you present uncompressed work and it doesn't have to do anything to execute effects.

Koz

But FCP is fairly clever. Even if you've got nested edits and lots of filters on many clips to make up en effect, there's only ever one decompression (for each piece of media) and one recompression back to the timeline codec. You can't really get much better than that for native editing.

Graeme



[www.nattress.com] - Plugins for FCP-X

>>Also, what is the rationale for adding on an additional pci firewire card to run the DSR 11 deck?<<

It's thought to be better to give each firewire device it's own bus to reduce the incidence of frame skipping. This is a hot issue, with many people claiming it is imperative, and many claiming it's a waste of time and money.

Personally I reckon stay away from Firewire devices if you can. Get some internal storage installed instead.

I also agree with everyone else in that there is little difference between uncompressed DVCAM and compressed, for all practical purposes. The DSR-11 route is fine.

If you wanted to move to HD, that would be a whole other (exceedingly expensive) kettle of fish.

A few more answers:

The additional pci firewire card would be for the drives. Put the DSR-11 on the onboard firewire bus. I have a similar setup as you do, albeit with an assortment of 500GB and 1TB firewire drives I swap around a lot. Works like a charm for me. In any case I think that you first need to upgrade your external drives and would vote for fw 800's on a separte fw 800 pci card as above. The reasoning here is that if you someday add a device like an AJA I/O to capture or playout SDI or component video, then you will need to keep the main bus free for that too. This also would leave an upgrade option to HD plus a raid solution open for the future.

To output uncompressed to tape: yes, then Digibeta via SDI. That's again where a device like the AJA I/O becomes a necessity, plus of course a deck (rental or purchase). Or, play your master sequence out to an uncompressed quick time file, put that on an external drive, and send the drive over to a post house and have them make the playout to a tape master. I do it all the time, both for tape and DVD mastering. Much easier, far cheaper and more reliable. Let the pros do the mastering, because it's not really just a matter of plugging in a deck and hitting record like with the DSR-11. Unless you are creating tape masters almost on a daily basis and are getting paid well for them, upgrading your rig to handle DigiBeta mastering will be a losing proposition financially.

For all your questions re codecs, filters, fx etc., Graeme is definetly the Grand Wizard here. Send those queries his way.

hth,
Clay

The picture is getting clearer. One thing is still murky. How do you uncompress a sequence in FCP before appllying filters and/or special effects? And then recompress it?

Also, hasn't the DVCAM format already compressed the video that is recorded on tape, and the firewire transfer from tape (via the dsr11) into FCP, a lossless transfer? If so, how can one decompress video whose source has already been compressed?

And after applying filters, etc., to the decompressed material, I will not lose the advantages when I recompress it back into the timeline codec?

As for adding another internal drive, are there any recommendations?

Thanks again.

<<< how can one decompress video>>>

You can convert compressed video to uncompressed and what you get is all the picture damage of the original compression carried in a new excellent format.

The picture doesn't suddenly become uncompressed quality.

I can't think of a good analogy, but it's the same effect as playing an old phonograph record into a multi hundred thousand dollar recording studio. The sound will never get any better than the original record, but now, it won't get any worse, either.

All these exercises are to try and not add any *more* damage.

Koz