accuracy of Vegas' waveform monitor and legality of generated media

[Glenn Chan]

Gotcha on the beta master, thank you. I did just read something about how capturing with different decks gives different results; I've searched and searched and can't find the thread, though. Maybe it was referring to decks that add setup.

Setup can get "added" during digital <--> analog conversions. 16 (digital luma value) either gets translated into 0 or 7.5IRE.

Some cameras record black at 2 (digital luma value), which can get translated into 7.5IRE if the deck puts 16 (digital luma) at 0IRE. That's not a good practice though.

Suppose you have a digital tape and you are transferring digital. If you capture over SDI, some decks will apply chroma smoothing/interpolation. If you capture over firewire, it copies your video EXACTLY and chroma smoothing/interpolation is up to the DV codec. Apple's DV codec doesn't add chroma interpolation when decoding DV. Vegas's doesn't.

see http://www.kenstone.net/fcp_homepage..._nattress.html

Glenn, do you work in video (and in Vegas as well?) for your day job?

Not yet. ;) Right now I'm in university for Radio and Television Arts. Although they don't teach you that much stuff there... a lot of what I know is from reading and doing stuff. There's lots of knowledgeable people and good resources on the internet. I really don't know all that much, and I've been wrong many many times.

[Mike Kujbida]

If anyone wants to get REALLY confused about the 0 IRE/7.5 IRE issue, Videohelp has a very interesting thread at http://www.videohelp.com/forum/viewtopic.php?t=259098

Mike

[Bill Porter]

Glenn,

True, there are a lot of knowledgeable people out there, but not all of them have around 3,000 posts, like you and Edward Troxel. I'm jealous you know enough to be ABLE to be so helpful! LOL
And of course I deeply respect that fact that everybody who posts, does help each other.

It's funny, when I use Photoshop, any MS Office product, or a couple of CAD programs, I can use them as extensions of my own hands, if you know what I mean. I navigate without even thinking about it. CTRL+ALT+T, Right click+A, Enter, bam bam bam, just knocking out steps one after another as fast as I can move. But in Vegas I know precisely what I want to do, I just can't make my "hands" move the way I want them to! I need a "DWIM" buttom... Do What I Meant, LOL

Question about decks - Why are there $4,000 decks? I thought all they did was capture. I use a little camcorder for capture so I don't wear out my DVX, but I'm always wondering "Can it be this easy? Am I missing something?"

[Glenn Chan]

High end DV decks run around $8k. The main feature is SDI output so you can work uncompressed (which is the 720X486 frame size) and transfer video digitally. When you want to print to betaSP or digibeta, uncompressed will give a little higher quality.


By uncompressed I mean the CCIR 601 format (something like that) with 720X486 frame size. You can work uncompressed with 720X480, but most capture cards don't work at that frame size.

But yeah, there's nothing wrong with a $300 camera. Mass production makes consumer stuff much cheaper.

It doesn't compare to the $100k you might be paying for some HD decks though...

but not all of them have around 3,000 posts, like you and Edward Troxel.

There's a difference between quantity and quality. Heh... :P

[Bill Porter]

LMAO, modesty at its finest


If my intention is to end up having a documentary broadcast, and as you said, they'll most likely want it on beta, should I be capturing with a deck then? (And taking that capture home and editing it, rather than capturing with my second camcorder and editing that)
Or will the difference not be noticeable since it's not for film blowup?

[Glenn Chan]

If my intention is to end up having a documentary broadcast, and as you said, they'll most likely want it on beta, should I be capturing with a deck then?

Not necessarily. If you transfer firewire, you'll get an exact copy of the video/picture.

If you transfer SDI, the deck has to uncompress the DV footage and send that over SDI. Over multiple generations, you technically lose some quality.

2- Not sure how you'd transfer your project to an online system. You could always print off to tape, although the dissolves won't carry over (as in, you can't apply color correction to underneath the dissolves).

[Bill Porter]

I'm going to repay your friendliness by pummelling you with questions, but hey, it's good for ya, LOL

If firewire would produce an exact copy, and SDI is lossy, why does spending anything (let alone thousands) on a deck so you can transfer SDI, make sense?

You mentioned SDI output = 720x486 = uncompressed in your post before this one, in this thread. So, I don't get why ya say "If you transfer SDI, the deck has to uncompress the DV footage and send that over SDI."

[Edward Troxel]

Originally Posted by Bill Porter

So, I don't get why ya say "If you transfer SDI, the deck has to uncompress the DV footage and send that over SDI."

DV IS compressed.

[Glenn Chan]

If firewire would produce an exact copy, and SDI is lossy, why does spending anything (let alone thousands) on a deck so you can transfer SDI, make sense?

DV frame size is 720X480.
ITU.R CCIR 601 format (something like that; SDI works in this format) has a frame size of 720X486.

Suppose you want to capture your DV footage. The way Final Cut Pro works, it tries to resize DV to fill the 720X486. It wastes a lot of time rendering.

The following article goes into detail about that:
http://www.lafcpug.org/feature_capture_card.html

SDI also has a minor benefit in that it does chroma interpolation for you. This saves time rendering. Some programs don't even have a chroma smoothing interpolation filter. Chroma interpolation is handy only for keys and secondary color correction, or if you have 'chunky' color.
http://www.lafcpug.org/Tutorials/bas...ma_sample.html

[Bill Porter]

Thanks, guys. I'll respond later - I'm reading from those links but this much info at once is like trying to take a sip from a fire hose, hehe