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Telecine DVCAM compression, and framerate


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#1 Dan Lahav

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Posted 22 June 2005 - 03:59 PM

Bare with me since I'm somewhat of a newbie... I recently had some Super16 footage telecined by CCI in LA. They are equipped with Davinci 2k and Spirit. The quality on the monitor was incredible during transfer. I had them transfer to DVCAM. Was this a good idea? I realize DVCAM compression gets rid of some color information, but what other pluses and minuses does this format have? I ask because I hope I transferred to the right format...

Also, I'm probably going to be editing my film on Sony Vegas or Adobe Premiere/AE. What should I render out/set my timeline at? 24P w/ 2:3:3:2 pulldown? 30i? etc?? Thanks!
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#2 Rolfe Klement

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Posted 22 June 2005 - 04:21 PM

DVCAM has huge compression so....

most of the time for video output projects I get a cheap one light of all the negative rushes - this is then taken into your NLE (better to do this on DVCAM - cause of timecode)

then an EDL is done in FCP or Avid or Premiere

The EDL is taken to Telecine with the Negative and the rushes graded to Digibeta - called TK Rushes

Then a final audio conform etc is done with the AIFF, WAV files , EDL, titles etc in smoke, flame, inferno etc and output to Digibeta or higher - this is called the MASTER

thanks

Rolfe
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#3 Dan Lahav

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Posted 22 June 2005 - 04:35 PM

OK you just confused me even more with all the technical jargain... :(

Can you answer any of my questions...? Are you saying I should have transferred to Digitbeta? What about the second part of my question? Thanks



DVCAM has huge compression so....

most of the time for video output projects I get a cheap one light of all the negative rushes - this is then taken into your NLE (better to do this on DVCAM - cause of timecode)

then an EDL is done in FCP or Avid or Premiere

The EDL is taken to Telecine with the Negative and the rushes graded to Digibeta - called TK Rushes

Then a final audio conform etc is done with the AIFF, WAV files , EDL, titles etc in smoke, flame, inferno etc and output to Digibeta or higher - this is called the MASTER

thanks

Rolfe

<{POST_SNAPBACK}>


Edited by Dan L, 22 June 2005 - 04:37 PM.

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#4 David Cox

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Posted 22 June 2005 - 06:19 PM

OK you just confused me even more with all the technical jargain... :(

Can you answer any of my questions...? Are you saying I should have transferred to Digitbeta? What about the second part of my question? Thanks

<{POST_SNAPBACK}>


Hello,

I think Rolfe was making the point that Digi Beta has a lower compression ratio than DVcam, so has a theoretical higher picture quality.

However, whether that makes a difference to your project (and to answer your second question), depends a little on your final destination - i.e. what are you going to show your project on?

For example, if you are going to show on DVD, then your format choice is fine. DVD's are also reasonably heavily compressed and you have picked a format that is convenient and inexpensive for the editing software you mentioned.

On the other hand, if you planned on putting your final edit back to film to show in theatres, then the compression used for DV CAM would probably slightly degrade your final film compared to DigiBeta. Strictly speaking though, if you were going back to film you should look at HD solutions for this.

Again, for your timeline settings it depends what you are going to show your stuff on. For film output, you will need 24P as that is the frame rate of a film projector. If you are showing on US TV, your 60i setting (NTSC or 30 frames per second interlaced) is probably what you need to create a master that can be playout to video or record to DVD. As a mixture of those two, you can complete your work in 24P and then add "3:2 pulldown" to create an NTSC (30 frames per second) master for TV at the end.

Hope that helps :-)
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#5 Anthony Schilling

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Posted 22 June 2005 - 08:20 PM

The new version of Vegas, Vegas 6.0 supports digibeta and DV. for my next project, I'm hoping to capture the transfers from digibeta.. do my edit and sound sync, then print back to digibeta for the master. anyone think this won't work?
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#6 Rolfe Klement

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Posted 22 June 2005 - 10:00 PM

As David said.

The only other change would be in the order you do things. The TK session is almost the final thing I do, not the first thing - even for heavy special effects work - don't get caught up in the colour look of the project until the edit and music are in place - then having a good colour grade is the icing on the cake - after that you need to add titles and music - this is called the final conform

The main reason for not doing a telecine (TK) session before an edit is money... at £500/hr you don't want to waste time getting the colour perfect on the trees in the background if you are not going to need the shot at all

As regards Digibeta etc - the computer needs 10 bit SDI inputs - as made by bluefish444, blackmagic etc. These use custom codecs which are supported by various edit systems - or you can go higher quality but then cost goes through the roof

EDL - edit decision list - list of in and out points made by your edit software
NLE - editing software

thanks

Rolfe
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#7 Michael Most

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Posted 23 June 2005 - 01:07 AM

DVCAM has huge compression so....


DVCam has a compression ratio of 5:1. I wouldn't call that "huge," especially when you consider that Digital Betacam is more than 2:1. What does happen in DV, however, is lower chroma subsampling. In the case of NTSC, the sampling is done as 4:1:1 (in PAL, it's 4:2:0). That means there's less chroma information being passed, which can be significant when attempting to either color correct or extract mattes from that material.
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#8 Tomas Koolhaas

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Posted 28 June 2005 - 03:29 PM

Hello Dan,
As has been stated before in this thread, what format you telecine to is based on what your plan is for your project: is it for screening at festivals in theaters or is it for TV.
Do you want to edit only on a AVID type system (which are reffered to as NLE- non-linear editing)
which would limit you to having your output on Mini-DV or DVCAM tape (which in the scale of professional video formats are pretty near the bottom).
If you want to have a very good quality "master" (which means your final finshed piece) that does your original camera footage justice, you would probably want to have telecinied onto HDCAM, then had down-conversions made to DVCAM for your OFF-LINE EDIT (on an NLE system such as AVID), then take your offline edit and do an ONLINE EDIT (on a sytem like NITRUS for example) back onto HDCAM so you have a HDCAM "Master" of your project which does your super 16 footage justice, and is high quality enough to be projected on a large screen.
Cheers.
Tomas.
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#9 Stuart Brereton

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Posted 28 June 2005 - 04:09 PM

I've just come from a Telecine session where we were discussing this very question. Obviously, you want to use the highest quality format you can afford, or that fits your post pipeline.

The colorist I was talking to was of the opinion that as long as you are not doing specialist work, like green or blue screen, and you are not planning to do extensive grading of your final cut, then DVCAM is fine. If you're finishing for TV, then most people wouldn't be able to tell the difference between DVCAM and DigiBeta, certainly not on a domestic TV.
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