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When is Digital not Digital? Firewire or SDI?
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[Andy Taplin] “Would you therefore reccommend capturing via SDI uncompressed to get better quality after rendering in AFX? What codec would you render out with (Sheer?) and lastly, how much bigger are the files capturing using SDI uncompressed compared to Firewire DV – which I guess comes into FCP at 3.6MB per sec?”
If you’re working in broadcast, then Uncompressed SD 720×486 is the way to go. If you’re working in consumer / corporate, then it’s your choice as to which way to go. I work in both formats depending on the output. For a DVD, I’d probably just stay in the DV codec all the way.
When rendering in AFX, render in the native codec that you’re editing in or you’ll end up with a double render. That is if you render in Lossless in AFX, then FCP will re-render the file to whatever codec you’re using so you gain nothing but an extra set of renders. For DV based project, just use the DV-NTSC codec for rendering in AFX and make sure to set up your Comp size to 720×480 AND render lower-field first.
SD 8bit is generally about 20MBps and SD 10bit is about 30MBps+. You’ll need a capture card and minimum FW800 RAID drives to work in SD uncompressed 8bit and a SATA or Fibre Channel RAID to work in 10bit.
Walter Biscardi, Jr.
https://www.biscardicreative.comDirector, “The Rough Cut”
https://www.theroughcutmovie.comNow Posting “Good Eats” in HD for the Food Network
“I reject your reality and substitute my own!” – Adam Savage, Mythbusters
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I’d go along with that – it’s a lot of extra money for gains your customer may never see.
If there’s something special and short, though, you might consider cutting and rendering a DV edit, then importing that into AE for color and effects work before outputting an uncompressed file – which should compress a little cleaner to mpeg2 for DVD than a DV master will … though you might want a better Compressor.
Otherwise, the “next big thing” is high definition … if there’s an investment / learning time decision coming up, it might be worth starting to think about HDV / HDTV workflows now, with FCP 6 maybe due an’ all …
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BUT…the BIG advantage of SDI at the uncompressed codecs is that your graphics, titles, stills all benefit from the 8 or 10 bit uncompressed rate. Thus while your tape footage is still compressed 5:1, your graphics, stills and text isn’t…and will be far sharper.
PLUS…you benefit tons for being able to color correct and add filters at uncompressed 4:2:2, as opposed to DV 4:1:1.
In order to acheieve this element of better graphics and color correction, is it necessary that my DV footage be captured through an SDI input? Or can I still capture via the 4:1:1 firewire, and have this footage on a timeline that will allow 4:2:2 output via SDI?
Thanks!,
Ross
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Hey gang….
Here’s my two cents… I agree totally with what everbody is saying completely. Its a tough choice sometimes figuring out which route to go when doing DVCAM/DV and SD video. And all the responses are very knowledgeable. But I have to say that almost everybody missed the most important point (or question depending on how you look at it). The first question you need to ask is: Where is this video going? Broadcast? Corporate? DVD? Interent? The answer to this question should give you the direction you need. If you are editing a show for broadcast, then maybe firewire isn’t the way to go UNLESS you are using DVCAM and a descent level of video deck that has SDI out and a black level conversion (or compensator) built-in.
Remember, DV has a black level of 0 IRE and broadcast TV has a requirement of 7.5 IRE. That would mean alot of color correction to adjust your black levels to proper standards. Now, if you are going to any other format such as DVD or Corporate Video, its not such a big deal.
So…. for broadcast TV, I use and SDI input for all of my video so that I have the proper black levels. Otherwise, if its a video for company use or DVD, then I will use firewire. Now, please, don’t get me wrong. I’m not saying that firewire is not acceptable. Firewire is great but it is easier for me to input using SDI so that I have one less thing I have to do to ge my video ready for broadcast.
The whole game changes once you go HD, such as Walter. The video equipment is a higher standard and higher quality, so firewire ingestion is proper for broadcast. But standard DV, has to be looked at differently, according to your needs.
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Wayne Carey
Schazam Productions -
[walter biscardi] “[Andy Taplin] “Using DVCAM you’re saying there is no difference between Firewire and SDI?”
Nope, capture quality will be exactly the same.”
Walter, I have to respectfully disagree. Have you every actually captured some DV25 footage via firewire, then captured the exact same thing via SDI and compared the two? I know all the theory about how firewire is lossless, you don’t get anything more than what you started with, digital is digital, etc, etc,. BUT capturing a DV25 tape via SDI to an uncompressed codec looks better than capturing straight through firewire-primarily in terms of chroma smoothing. The colors hold up better through color-correction presumably because your 4:1:1 color space now resides in a 4:2:2 world – even though you don’t end up with more color resolution than you started with. I know there are many opinions on this, and that Natress has some filters that do essentially the same thing I’m talking about here, but you don’t really know until you do a test and look at it with your own eyes. Now, I’m not saying you haven’t done this, but I have, and to my eyes there is a clear advantage to bringing in DV25 over SDI into an uncompressed codec – especially if you are going to do any color-correction.
Chris Tomberlin
OutPost Pictures -
Wayne,
0 setup is not unique to DV all digital formats offer no setup (DV,HD). 7.5 setup is for analog NTSC output and is not just for broadcast productions. Anything that will be output in analog (component or composite) and displayed and/or transmitted on a NTSC monitor should have 7.5 setup added (unless you what to recalibrate the monitor’s viewing settings for zero setup.)
SDI and DV have no setup so black is at 0. There is no additional color correcting needed to comply with NTSC analog output since
7.5 setup can be added via the output via the video card, tape deck or digital to analog converter.One last note SDI is not a losseless “clone” as each I/O (in/out) of dubbing involves a decompression/compression cycle. SDTI is considered the proper method for “cloning” SDI material.
Tony Salgado
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Wayne
DV black level not broadcast standard? This is an NTSC only concern I think? Over here in PAL land when I input DVCAM (via Firewire) into M100 the balck level from the 75% bars looks spot on at 0 volts.
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At the end of the month, I’m going to be working in FCP on a video on-site at a meeting. Last year, I handed off my DVCam master recorded on a DSR-45. Everything was shot DVCam and brought in via FW.
The playback in the ballroom was BetaSP. The video engineer made a dub from my DVCam master to BetaSP for playback. The engineer mentioned that my blacks were too black, but since we didn’t have time to troubleshoot, they used the tape as is.
Even back in my Digital Beta mastering days, when I made the dub from DBeta to BetaSP or any analog format, the setup change was done at the dub. I never made my digital masters @ 7.5 IRE.
What should be the proper progression of DVCam to BetaSP for playback? I don’t think I should be making the change in FCP, but do they have control over the setup out that DSR-45 when they make the component dub? Should they consider bringing along a proc amp and put it inline between the DSR-45 and the BetaSP deck. (I think it was a 2800, but I’m not sure). I should probably have this nailed down before we get there this year!
I really appreciate the input!
debe
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My DSR-1500A has a menu option for adding set-up on analog output. I also have it added for proper viewing on my broadcast monitor. Otherwise the output will look too dark.
pxlmvr
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[Chris Tomberlin] “Now, I’m not saying you haven’t done this, but I have, and to my eyes there is a clear advantage to bringing in DV25 over SDI into an uncompressed codec – especially if you are going to do any color-correction.”
If you capture DV25 via Firewire and DV25 via SDI, they are one and the same quality. If you capture DV25 to Uncompressed SD 8bit, they are one and the same quality.
It is only after you apply any type of filtering or graphics that the advantages of an uncompressed timeline will be evident.
What is the final output of the product? DVD. For DVD there is no reason to bring in DV / DVCAM at anything other than Firewire. Not that I’ve ever seen in my experience.
Walter Biscardi, Jr.
https://www.biscardicreative.comDirector, “The Rough Cut”
https://www.theroughcutmovie.comNow Posting “Good Eats” in HD for the Food Network
“I reject your reality and substitute my own!” – Adam Savage, Mythbusters
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