HDV output to Betacam SP

Hi

I?ve got a doc shot on HDV 1080i60 that?s now going to be dubbed to Betacam SP (ntsc), and I?ve got the chance to go to a production house that has one of these decks.

I?m wondering if I should take the HDV camera/deck and connect it directly to the Beta deck (and hope for the best), or if I should take a hard disk with a .mov; and in this case, to which format I should downrez it to, in the case their suite doesn?t handle HDV. Would it be uncompressed 10-bit ntsc, or 8-bit?

I did do a search, but most info relates to DigiBeta.

Thanks


Shane, derekmok, filmman and ChrisMoriarty, thanks for answering my previous post of a related problem; I replied with my conclusions some days later, but by then the thread got pushed back a few pages.
[www.lafcpug.org]

You really need an installation that can play your show on a real computer and convert on the fly to Component NTSC and two analog audio channels.

Component NTSC has three video cables; basically black and white video, red and blue. That's what the video system needs to be able to provide at both the deck and the computer.

If that fails, some BetaSP machines will accept "S" video. That's basically two cables; sharp clear black and white and all the colors fuzzy and smooched together.

If that fails, you're stuck with composite NTSC; basically one wire with everything smashed together. That's the worst one.

The analog audio channels will burn you long before the video because everybody has gotten so used to being sloppy with levels. Digital is very tolerant of any audio that doesn't smash digital zero. Not so analog. Analog has crunchy overload (too high) and hissy underload (too low) just waiting for the unwary.

It will be necessary to put bars and tone at the front of your show (from the effects tab--video generators). Thirty seconds should do it. I don't know if any of the colorbar patters will work with an HDV timeline. And I won't know until Tuesday...~!@#$

OK. Sound. I produced a video a while back illustrating the difference between DV-ish quality sound and BetaSP. The HDV sound should be the same quality as regular DV.

[www.kozco.com]

Open that video up on a DV timeline, render, and play the whole thing. The picture on the screen will be the BetaSP meters. Compare that with your Final Cut meters. That's where your Final Cut meters should be.

You do have to modify your BetaSp machine audio channels--all that is covered in the instructions and you can see me doing it in the video.

Good luck.

Koz

Svideo = sharp clear black and white and all the colors fuzzy and smooched together

Speaking of ... I have a situation with a lot of betacam Sp rushes digitalized in Dv quality through the Svideo input of a Dsr 11 deck (passing through e/e -> firewire to mac)

the quality is... not so good ! lot's of "cross color", what we call in French moirage (any zone with close tiny lines in the image provokes awful moving horizontal bars )

would I see a major improvement by recapturing the edited footage (on line confo) in uncompressed quality with component or sdi ?

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A Day late & a Dollar-short Productions

I just finished my first HDV feature a few days ago, and I'm thinking that 10 bit uncompressed is the best way to go.

Therefore, I would think you should put your documentary on a DVD disk as a .mov file. Your HDV camera won't be able to carry the 10 bit uncompressed video.

You should be trying to get the biggest size frame for your movie, having used HDV, and to take advantage of the 1440x1080 frame size.

I'd also call the post house and ask them if you should bring the movie on the DVD disk as I've suggested. I'm sure they'll tell you if that's the way to go.

<<<(any zone with close tiny lines in the image provokes awful moving horizontal bars )>>>

Video Compression in 1945 consisted of adding up the three color channels, red, blue, and green according to a formula to produce an excellent black and white signal. This kept all the black and white TV sets happy. Then combine the color signals into each other according to a very complicated formula, greatly reduce their sharpness, impress them on a "color carrier" and combine them with the black and white. A color television knew where to go to look for this special color signal and what to do with it. Black and white TVs, if they saw the signal at all, displayed it as a very fine, delicate screen door pattern over objects that started out at the station in color.

Sorry, colour.

If you don't maintain strict relationship between all the signals (and they get messed up more often than you think), then any black and white image fine and crisp enough to look like the color signal will display as rippling rainbows or areas of false color.

When Johnny Carson was doing the "Tonight Show," he hated the video shader and would come to work in a whole outfit that looked like this:



His whole body would shimmer and shake and rainbow for 90 minutes.

Full Component video; black and white, red, and blue (I'm abbreviating here) goes through the arithmetic step but is missing the encoding and combining steps and should look perfect. "S" video sends the color signals through arithmetic and encoding, but leaves out the combining step. The colors are fuzzy and encoded, but they're carried on their own wire separate from the black and white and should never rainbow.

Composite video has everything on one wire and it's the only one where interactions between all the signals are possible. It's also the only video process you can broadcast on analogue television.

So if you have rainbows, it doesn't matter what people are telling you, somewhere in the pathway, the signal was damaged in a composite process. It can happen, by the way, in your monitor..... Just thought I'd throw that in. If you're viewing the signal on a TV set, you can run into problems there.

Almost anything you do will look better, but yes, full-on component is the way to go for best quality.

Koz

<<<would I see a major improvement by recapturing the edited footage (on line confo) in uncompressed quality with component or sdi ?>>>

Something has to make the SDI and that is the step that needs care. You may not be able to tell the difference between uncompressed and DV quality. The damage happens at the analogue step.

Just to throw boue in the game, do you know where the BetaSP tapes came from? If they were recorded composite from a ratty source, then the damage may be burned into the video no matter what you do.

You're not in SECAM, are you?

Koz

To get back to bernardojv's question, he needs to know what to bring in to the post house.

Are they doing the dub for you and helping with the setup? Or do you just have access to the equipment and you're on your own? If it's the latter, then re-read Koz's advice above and try to ask someone there for setup advice. If they're going to help you then ask them what they need: HDV master or an 8-bit .mov file (I think 8-bit, only cuz I'm not sure that 10-bit would add much quality to HDV). If so, drop your final HDV sequence into an 8-bit timeline (it will letterbox) and export that QT to a hard drive to bring in. Then they can play it back in FCP and adjust output accordingly on the analog gear (so DO put the bars and tone in there, very important).

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filmman
I'd also call the post house and ask them if you should bring the movie on the DVD disk as I've suggested. I'm sure they'll tell you if that's the way to go.

Uh, NO they won't. You need to download the videospace calculator from Digital Heaven. You would see that unless his doc is 3 minutes long, there's NO WAY it will fit on a DVD data disc.


JK

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SCQT! Self-contained QuickTime ? pass it on!

I stand corrected. Okay, then is an external hard drive with the movie saved on it as a 10 bit compressed the way to go? Why do you suggest 8 bit? Are you sure there is no improvement in quality?

He'd have to do a test, not sure if 10-bit gives much more quality than 8-bit, given that the source material is heavily compressed (HDV) going to analog (BetaSP). If he was going to DigiBeta or was starting with higher quality HD it might make a difference, but at some point you're just adding extra file size with no visible increase in quality. I just had to downconvert DVCProHD 720p to DVCam, and 8-bit was fine for that.

1 hour @ 8-bit = 71GB; 1 hour @ 10-bit = 94GB

JK

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SCQT! Self-contained QuickTime ? pass it on!

no no not secam , - secam out of beta (aka component coding to secam was barely used in public channel in the 80's / secam is an odd french particularism only used in final multiplexed UHF/VhHF by now - for diffusion) / as a working standard, France is pal land by now

those beta came straight out of a pal beta 400 at the time (1999/2000) (old tapes / fuzzy cam itself) / not every thing is affected : it depends of light, conditions, on witch foot I stood up the day of shooting ??? (my god I won't regret analog video)

my problem is to improve final render the best I can,
with the help of Joe's Maller noise filters I can improve ... but the area in blurred witch can be a problem / I mean I've been through this... thing is : is it worth to go the recapture road for an online confo real component to uncompressed

and Koz your are going to tell me ... it should ... witch is the only answer I guess

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and by the way you are right about the monitoring : at the end of my chain on the same monitor: Svideo looks WAY better than composit, I an just trying to figure what it would look like on Tv ?

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A Day late & a Dollar-short Productions

thanks for all replies, wow, much info, have to digest...

there is someone at the post house to help me, but I'm not so confident he knows as much as you guys

10-bit or 8-bit? Hard disk space is not a problem, and if there is no difference as far as quality goes, why not go with 10-bit just to be safe? Unless there's a clear disadvantage of this format in the whole compression process, and 8-bit is safer/more reliable/more predictable/easier to work with/etc?

Now for the really good news: they don't have FCP. They are Avid. I'm FCP. So... should .mov work, or do I need .avi, or .wmv? And if any of the last formats, how do I know I'm at the highest quality possible (equivalent to our 10-bit quicktime movie straight out of fcp)?

Neither BSP or HDV will benefit from 10bit. 8bit uncompressed would be best. Better to let FCP do the downconvert (hight quality scaling on) than the deck or camera as they're poor on the downconvert. Best would be just to plug the HDV deck into a Snell & Wilcox or Terranex broadcast converter or ARC to downconvert to component for the BSP. Better still would be to avoid BSP and go Digibeta.

Graeme

Putting it on the HDV format and taking the tape and camera to the SP deck is probably simplest.
If you want another option you could always get the AVID codecs (http://www.avid.com/onlineSupport/supportcontent.asp?browse=&productID=0&contentID=10554) and render out a QT in 2:1 (1:1 would be a huge file and the resolution is beyond anything SP or even DigiBeta can replicate)
You would have to nail down what kind of AVID they have, but it's doable if every other avenue is closed.

ak
Sleeplings, AWAKE!